Pinking (pre-ignition) 1999 2ltre

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1963paul
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Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 30 Jan, 2017 10:48

So, I've had a couple of sensors replaced recently to cure a hot starting/ stalling problem, that's all fine, but now I noticed its pinking and I'm trying to locate the anti-knock sensors, just to see if the multi plug is dislodged, like I found on my generator plug ( it wasn't "clicked" in tight and my batt warning light would flicker occasionally, that's also fine now).
I had found a rubber "cap" pushed onto a small spout, just below the dip stick, which goes into the inlet manifold, had split, which I've temp repaired with superglue and tape, but it's still pinking, especially under load (steep hill).
Can somebody point me in the right direction under the bonnet on where to look, it's a bit tight under there!
Thanks.

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colb
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Re: Pinking (pre-ignition) 1999 2ltre

Post by colb » Mon 30 Jan, 2017 14:57

oem shows it as a ping sensor
http://www.realoem.com/bmw/enUS/showpar ... 3627568422

Not clear where it attaches to the engine in the diagram, they are usually bolted on the side of the engine block where they would pick up the engine noise. Looks like its a double unit with one connector.

oem link is to a 2.0l car built August 1999, worth checking for your actual model in case they changed anything during the build year.
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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 30 Jan, 2017 15:32

Thanks for that, I have seen that diagram before, but like you say, doesn't show where it is on the engine. I would imagine it would mean removing a lot of the stuff on top of the engine ( inlet manifold etc) to get to the sensors, unless someone has been there before and can tell me otherwise.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by Robert T » Mon 30 Jan, 2017 17:36

See Ignition and Knock Control on this page: http://www.pelicanparts.com/BMW/techart ... ystems.htm

Cheers R.
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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 30 Jan, 2017 17:48

Robert T wrote:See Ignition and Knock Control on this page: http://www.pelicanparts.com/BMW/techart ... ystems.htm

Cheers R.
Ahh, that's better, just as I thought, not easy to get at!
Thanks

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colb
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Re: Pinking (pre-ignition) 1999 2ltre

Post by colb » Tue 31 Jan, 2017 10:34

Had a look for Pinking problems and found this regarding the knock sensors, may be of interest to you in tracking down the cause of your problem.
http://www.bimmerboard.com/forums/posts/797779
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Del
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Re: Pinking (pre-ignition) 1999 2ltre

Post by Del » Tue 31 Jan, 2017 17:32

I would get it plugged into a diagnostic error codes reader - I'm note sure that your 1999 car would have an "engine management fault warning light". My 1998 one hasn't, 1999 may be borderline. Whilst "knock sensors" make small adjustments to avoid pre-ignition (often undetectable to the driver) I'm not sure that their actual failure would cause the pronounced "pinking" you are experiencing.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 31 Jan, 2017 23:31

colb wrote:Had a look for Pinking problems and found this regarding the knock sensors, may be of interest to you in tracking down the cause of your problem.
http://www.bimmerboard.com/forums/posts/797779

For some reason, that link won't open?

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 31 Jan, 2017 23:44

Del wrote:I would get it plugged into a diagnostic error codes reader - I'm note sure that your 1999 car would have an "engine management fault warning light". My 1998 one hasn't, 1999 may be borderline. Whilst "knock sensors" make small adjustments to avoid pre-ignition (often undetectable to the driver) I'm not sure that their actual failure would cause the pronounced "pinking" you are experiencing.

No, no warning lights, and funnily enough, on the way home this evening, window down, steep hill, didn't hear any pinking?, don't you just hate that!...not really sure if it's there, am I getting use to it? was it there before?, was that rubber cap I found split was the cause?...and the ECU took time to re-tune?...then the hill flattens off ! really annoying.
Think another trip to my local repair shop and plug it in, and see what's lights up.
Thanks for all the suggestions chaps, really appreciate all the ideas.
Paul.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 31 Jan, 2017 23:51

1963paul wrote:
colb wrote:Had a look for Pinking problems and found this regarding the knock sensors, may be of interest to you in tracking down the cause of your problem.
http://www.bimmerboard.com/forums/posts/797779

For some reason, that link won't open?

Yep, just tried again, and it opened...that chap must have changed every component bolted to the engine!..don't think I'll be going down that route...yet.

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colb
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Re: Pinking (pre-ignition) 1999 2ltre

Post by colb » Wed 01 Feb, 2017 09:46

http://www.bimmerboard.com/forums/posts/797779

Link on previous post works for me, here it is again

Yes he fell in to the trap of changing everything he could think of, been there done that :roll:

As to plugging it in to read codes rather than spend out at dealers/garage why don't you get yourself a code reader and do it yourself then post on here for guidance on what is found if anything? You will recoup the cost of a code reader the first time you use it. Plenty of suggestions on what to get on the forum. If your a novice on this sort of thing one of the cheaper code readers will suffice over going the whole hog and getting the computer based BMW software known as INPA which can be difficult to set up on a laptop.
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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Sun 30 Apr, 2017 10:01

UPDATE: Might we worth noting that pinking can be caused by TOO MUCH OIL!!..eventually the problem was found to be over filling (by me)!...over a litre was drained off.
The car was parked on a neighbours driveway one night, which was very steep, and on the way to work the following morning, the oil level warning light flashed on, I pulled over, had a litre in the boot, just chucked it in, as was running late for work, light went out, thought nothing more about it. :oops:

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Fri 02 Jun, 2017 14:35

I spoke too soon...the pinking problem, 'tho a lot better since the excess oil was drained off, is still there... :head:
So I am going to get the anti-knock sensors replaced anyway....it seems they can go faulty, and yet, pass all the diagnostic test with flying colours.
Anybody on here replaced them?...from above the engine, or tackle it from underneath?..any help would be appreciated...I do have access to a 4-post lift which would be helpful, if tackled from underneath

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Re: Pinking (pre-ignition) 1999 2ltre

Post by siwilson » Sat 03 Jun, 2017 07:30

Simple test. When I had my 2.0 I noticed the occasional pinking and found better fuel cured it. Do you use super unleaded or could you try a tank?
2001 M roadster S54 Laguna Seca Blue

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Sat 03 Jun, 2017 08:41

Have always used super, but to be fair, it shouldn't really matter what grade, the sensors and ECU should dial out any pre-ignition detonation. I'm going to change the anti-knock sensors anyway, they do age and crack overtime, and yet don't show any errors. Just want to know if anybody has done the job, and the best way to tackle it, from above and remove the inlet manifold etc, or from below ?

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Re: Pinking (pre-ignition) 1999 2ltre

Post by stevov » Sat 03 Jun, 2017 20:28

When was the last time the spark plugs were changed and what quality plug.

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Re: Pinking (pre-ignition) 1999 2ltrep

Post by 1963paul » Sat 03 Jun, 2017 23:37

stevov wrote:When was the last time the spark plugs were changed and what quality plug.
The plugs were changed a couple of years ago during its service, and were checked last week, all perfect.
The plugs that came out weren't standard,they had 4 electrodes and were well passed their sell by date, so the garage who did the service replaced them with standard plugs, it looked like the car, up to then, hadn't been serviced for a very long time ( it still had the original fuel filter, dated 1999)!..the pinking started about 3-4 months ago, and up to then had been running fine.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by stevov » Sun 04 Jun, 2017 08:07

Personally if you went to the trouble of checking 2 year old plugs last week I would have changed them as a matter of course. Did you check them on a spark tester or just a visual and regap. What brand are they.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Sun 04 Jun, 2017 15:57

stevov wrote:Personally if you went to the trouble of checking 2 year old plugs last week I would have changed them as a matter of course. Did you check them on a spark tester or just a visual and regap. What brand are they.
Yes, you're right, as they were out anyway, suppose should have changed them, but they were all ok, no evidence of glazing or soot, and they are NGK.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by stevov » Mon 05 Jun, 2017 19:45

Never had any issues with NGK as they are what I fit as standard to all my customers cars, but after 2 years anything is possible. We're they copper, platinum or iridium. As far as appearance a lack of soot is not in itself an indication of plug condition more and indication of fueling. If the plugs were too clean as in white, light gray it could be a sign of to lean which would create excess cylinder temp and possible pinking . Without a proper tester plug appearance is more an indication of fueling until a more apparent misfire developed which would result in the suspect plugs appearance being noticeably different . I have seen pinking leave little white marks on plug electrode insulation. When was your fuel filter last changed. Are all intake pipes and hoses secure especially downstream from the maf.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 05 Jun, 2017 21:43

I have just ordered new spark plugs (non in stock, that's Halfords for you)!, Bosch 4pk Super+, one of a number of recommended spark plugs, they have 4 electrodes. I will have a really good look at the old ones when I take them out for any white marks as you suggested. The fuel filter was changed at the last service, the one that came out was dated "1999" the year the car was built!...so it hadn't been really looked after. ..but to be fair, it ran like a dream! The garage I go to have checked for any air leaks ( no leaks), they had to replace a small hose last year, which was causing issues with ticking over and hot starts etc, it had split, and caused fuelling/ mixture issues, where it would "hunt" then start to misfire. Makes me wonder if that had caused a carbon build up, as that's when I started to notice the pinking after the hose was replaced. Any thoughts of "sea foam" engine cleaner?, where you spray it into the air intake.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Mon 05 Jun, 2017 22:47

I wouldn't spray anything into the air intake as it could damage the MAF meter and they are expensive.
The best advice for diagnostics is to do one thing at a time otherwise you can end up chasing your tail.
Fit your new spark plugs when they arrive as that is simple. If the pinking persists change the knock sensors since you have them on order anyway and that may cure the problem and anything else you try in the interim is not needed.
If you still have a problem after plugs and knock sensors then we can look elsewhere.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by stevov » Tue 06 Jun, 2017 07:01

therealdb1 wrote:I wouldn't spray anything into the air intake as it could damage the MAF meter and they are expensive.
The best advice for diagnostics is to do one thing at a time otherwise you can end up chasing your tail.
Fit your new spark plugs when they arrive as that is simple. If the pinking persists change the knock sensors since you have them on order anyway and that may cure the problem and anything else you try in the interim is not needed.
If you still have a problem after plugs and knock sensors then we can look elsewhere.
Some good advice. Also pay attention to the condition of the coil packs and wiring while doing the plugs. Connections, ground wires etc

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 06 Jun, 2017 10:13

Yep, you're right, plugs 1st, thanks for the input.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Thu 22 Jun, 2017 23:08

Finally got round to checking and changing the spark plugs. The old ones were NGK R (BK6RE), and they looked OK to be fair, so I have replaced them with Bosch Super4 (FR78X), because these were on the Halfords web page, when it asks what car you have (via the reg number), went for a test drive this evening, and, and it is 98% better, NO PINKING!, I say 98%, because there was a barely noticeable, slight "tinkling", which I hope will disappear over time.
So, I don't really know if the old plugs we're faulty or were the wrong ones anyway,or the heat range is different ie, are the new plugs slightly cooler?, I can't find a comparison chart for different plug manufacturers heat range, for all I know, they might be the same ?....anyway, I'm sure someone on here will know, be nice to find out.
If the slight tinkling doesn't go over time, ( and doesn't get worse)!, would a cooler plug be the answer I wonder?, and has anybody changed their spark plugs for the same reason? I would add that the engine, air filter, exhaust etc are bog standard, nothing has been modified, no fancy "cone" type air filter, no loud exhaust etc etc, pretty boring really.
Thanks for all the replies, suggestions so far, really helpful.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 04 Jul, 2017 10:41

Ok, it's been nearly 2 weeks since I fitted the new spark plugs, it has made a difference, I can drive another 5 miles now, from cold, before the pinking starts, before, I could drive for about 6 miles before it started. It's definitely not as bad, but it's still there. I had also disconnected the MAF for the last 4 days, made no difference ( didn't even get any warning lamps on the dash, other posts suggest a warning lamp should light up)?, and to be honest, I didn't notice any changes whilst driving.
So, next step, any thoughts on cooler spark plugs, engine cleaner in air intake ( after the MAF), engine cleaner in the fuel tank? De-coke specialist advertised on FB?..... Or cylinder head off?...I am thinking it's carbon build up, and gets hot, causing pre-ignition....it's absolutely fine when cold, no pinking whats so ever...anybody got any ideas?

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Re: Pinking (pre-ignition) 1999 2ltre

Post by BladeRunner919 » Tue 04 Jul, 2017 11:31

The fact that you noticed no difference with the maf disconnected and got no warning light is the stand-out comment. It sounds as though the car runs ok when it's in open-loop, but not when it's in closed-loop. I assume your engine light comes on correctly when you first turn the ignition on?

I think you need to run diagnostics on the car, and look at it in INPA with the engine running.

I think you're probably barking up the wrong tree by worrying about the spark plugs

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 04 Jul, 2017 11:44

Yes, the warning lamps are all ok. I have just dropped off the car to my local garage, he has got a " terra clean" chap coming round on Monday to de-coke the engine. The chap there also says as it only pinks between approx 2-3 thousand revs, that's a sign that it could be burning oil, no smoke tho', as the cat is filtering it out. So, we'll see if the terra clean does anything. The car has been plugged into a laptop, whilst driving it around, and it comes back as its absolutely fine, fuel trims ok, everything doing what it should, the timing changing as it should, no problems, it's all very frustrating.
Watch this space!

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Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Tue 04 Jul, 2017 23:11

I would have thought if the engine was coked up sufficiently to cause pinking you would notice unusual deposits on the spark plugs, which you did not, or excessive oil consumption which you have not mentioned.
I would now turn my attention to the knock sensors. You can see the output from these on INPA I believe but you need a willing voluteer to observe the changes, if any, during the actual pinking. It is no good looking with the car stationary or just driving around you need to catch it in the act.
Fuelling will not make any difference pinking is pre-ignition i.e. too advanced for the required conditions. Easy to sort in the old days of mechanically advanced distributors but then it was more of a problem then so all DIY mechanics knew about it!
You mention timing. Are you sure you are not looking at the valve timing (Vanos) rather than the ignition timing which is what would cause pinking?
I thought from an earlier post you had ordered knock sensors so if you have them already why not fit them?
Incidentally, I have a 2 litre also and my MAF was so ******* pardon my French :oops: that the car would not even start with it plugged in and yet ran well enough to drive the car with the MAF disconnected. There were no warning lights or fault codes on INPA whatsoever but a second hand OEM MAF sorted the problem and is still running 3 years later.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Wed 05 Jul, 2017 16:54

I haven't got round to ordering the knock sensors yet, as its such a task to get at them and change them, that will be the last thing to try if all else fails. The ignition and vanos timing have been checked, all ok, the plugs that I changed, looked ok, (new plugs fitted, still pinking),... :head:
The terraclean can only improve things, so no harm in trying it.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by Del » Wed 05 Jul, 2017 22:28

I would definitely recommend first getting the car plugged into a code reader to check if any errors have been logged on the ECU. Pinking due to carbon build-up is not at all common in these cars as they have traditional "port injection" and not the more modern "direct injection" to the top of the pistons which can cause serious carbonisation around the inlet valves.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Wed 12 Jul, 2017 22:17

Well, got me car back after its terraclean, went for a reasonable test drive, and........sounds ok.
Taking it to work tomorrow, about 11 miles on a A road, it would do about 7 miles before it started ( 5 miles with the old spark plugs), so, we'll see, but in general, after its clean, it's feels better, smoother pick up, better acceleration. :)

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Thu 13 Jul, 2017 23:57

:head: :head: ...it's not so bad, overall it better, the terraclean has done some good, but it's still pinking, tho' not as bad as before...next is to try cooler spark plugs, then poss some octane booster in a bottle.
I have come across another theory....yesterday my motorcycle ( Moto Guzzi V11 Breva) decided to spring a petrol leak, because the plastic petrol tank has developed a pin prick size hole, which I found out, is caused by the higher ethanol content that was introduced to our shores, I think within the last couple of years ( it's gone from 5% to 10% I believe), on looking into how to get over this problem, I found out that ethanol can cause pre-ignition on some engines, and the suggestion is to use octane booster, and looking back, my pinking problem might have started then, but not really took much notice at the time...just a thought.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Fri 14 Jul, 2017 09:49

Unless your local garage is diluting its petrol I would say there is definitely something wrong with your car as the rest of us are not having this problem. Think about how many M52 engines are out there it is not only used in the Z3!
Using octane boosters and the like is just disguising the symptoms the problem is still there.
You should not need souped up fuel and cold spark plugs as BMW put a clever system on board that would make their engines run on anything from chip fat to Formula One fuel. Well not exactly but you get what I am saying. I am in no doubt that our petrol is certainly higher in quality than many countries where BMW cars are on the road.
Unfortunately you need to persevere.
If your car really is pinking it is potentially doing damage over a period of time so it needs to be sorted out.
If your problem started at the point when you say poorer fuel appeared then that suggests that your ignition timing system is not working correctly.
If I had this problem I would change the knock sensors next and being difficult to reach is not an excuse to not change them but cover up the issue by other means.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Fri 14 Jul, 2017 11:45

Yes...I think you're right about the ping sensors, I am caught up in a situation where I am trying to avoid getting them done...the garage I go to are 100% sure that they are ok, they are working as they should, and it will be a waste of time and cost getting them changed. They keep saying the engine is worn and its burning oil, causing the pinking, and they said not to waste more time and money on it...its only done 118,000 miles...which is not a lot for that engine, and I suggested the de-coke, which is what the terraclean has done, but the mechanic did say that's is not the problem...even tho' its driving better now, so its done some good.
I think I will get the sensors changed, I've said it before I know...

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Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Fri 14 Jul, 2017 13:21

You will know best if it is burning oil surely as you will have to keep filling it up.
If it is burning oil to the extent it has coked the engine I am certain you would notice it on the spark plugs and by you regularly looking at the dipstick.
To burn a lot of oil either the piston rings are shot or the valve guide seals are passing. A simple compression check should rule out either of those eventualities.
My 2 litre is up to 150,000 miles now and does not really use oil and it does not pink.
Why are your garage so confident that the sensors are ok? The only real way of telling is to monitor their output when pinking occurs and even with a rolling road it will probably be difficult to replicate pinking under standstill conditions where you can check the sensors.
Sounds to me like they just don't want the job because it is awkward and there will not be any profit in it by the time they mess about getting the sensors swapped over.
I admit that knock sensors are one of the more reliable sensors fitted to modern cars but that does not mean that they cannot fail it is just unusual.
If you hook the car up to INPA it should be able to tell you if it is the front or rear bank of cylinders that is the issue in which case you may only have to replace one sensor.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 24 Jul, 2017 19:22

BladeRunner919 wrote:
Tue 04 Jul, 2017 11:31
The fact that you noticed no difference with the maf disconnected and got no warning light is the stand-out comment. It sounds as though the car runs ok when it's in open-loop, but not when it's in closed-loop. I assume your engine light comes on correctly when you first turn the ignition on?

I think you need to run diagnostics on the car, and look at it in INPA with the engine running.

I think you're probably barking up the wrong tree by worrying about the spark plugs
Going back to this, when I disconnected the MAF and nothing changed, forgive me for sounding like a complete dork, does that mean the MAF is faulty?, and does the MAF control the air temperature going into the engine?. It's hot today, bad pinking, twas much cooler before, and pinking was almost non-existent.
Sorry to keep going on about it...and thanks again for suggestions...keep them coming.

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Re: Pinking (pre-ignition) 1999 2ltre

Post by colb » Mon 24 Jul, 2017 20:42

Disconnecting the MAF will result in the car going to default running settings. The effect this would have would be dependent on how the rest of the sensors and engine are performing. The MAF measures the amount of air passing through it and reports to the ecu. The measurement it reports helps the ecu to determine the correct settings for the engine to run correctly in conjunction with other sensors like the exhaust sensors. If you didn't notice any difference with the MAF disconnected it could be down to a bad MAF. Try cleaning the MAF sensor with electrical contact cleaner, do not touch the sensor with anything just spray the cleaner on it and allow to dry before putting it back in, touching it will destroy it.

Should the MAF be replaced only use a reputable make, Bosch or Siemens do not buy cheap ebay ones, they seldom last or work, been there done that. Alternative is to try a known good used MAF from a breaker. New they are not cheap so if you have anyone near you it might be an idea to swap a good one just to see if it resolves your issues.

My 1.9 had a bad MAF, power was down and idle was unsteady, as soon as I fitted a replacement MAF all my problems went.
Colb
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Re: Pinking (pre-ignition) 1999 2ltre

Post by Del » Mon 24 Jul, 2017 21:08

Most modern MAFs contain an air temperature sensor so that they don’t just measure air passing the probe but also, by knowing the air temperature, the ECU can take millisecond calculations as to the density of the air going into the engine and adjust the mixture accurately. In hot conditions, the air will be less dense. If you disconnect the MAF sensor the ECU will make some factory approximation for air temperature which may be inaccurate in hotter or colder conditions.

As you have noticed a definite difference in hot weather conditions, you may well have hit on the problem. A weak mixture is one of the possible causes of “pinking”. It may be that your MAF is not measuring the air temperature properly and is not allowing the ECU to compensate for less dense, hot air. There is nothing else in the engine management system that would be so sensitive to the ambient air temperature outside the car.

therealdb1
Joined: Tue 25 Jun, 2013 22:47
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Mon 24 Jul, 2017 22:55

The bad news for the OP is that a malfunctioning MAF will probably not show up on any code reader. Substitution is the only test and they are not cheap!
As I have said before my MAF failed so catastrophically that the engine would not even start when it was plugged in. No errors and no warning lights.

1963paul
Joined: Sat 19 Jul, 2014 14:19
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 25 Jul, 2017 23:11

Bought a 2nd hand MAF from a scrapped Z3, arriving Thursday ( it's guaranteed), so see what happens then.

therealdb1
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Wed 26 Jul, 2017 19:51

:lol: That's exactly what I did Paul just to prove it was the MAF.
3 years later I am still using it!

1963paul
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Thu 27 Jul, 2017 00:36

therealdb1 wrote:
Wed 26 Jul, 2017 19:51
:lol: That's exactly what I did Paul just to prove it was the MAF.
3 years later I am still using it!

For £19 it's worth a punt, I also got some Halfords contact cleaner as I suspect it may have been on a dusty shelf somewhere, and thought I would clean my existing MAF, made a huge difference in the short drive after, it now revs up to the red line easily, (didn't know it had a rev limiter till then)!. Looking forward to the drive to work tomorrow, especially on the way home when it's warmer to see if the pinking is still there ( the short drive this evening wasn't long or warm enough to bring it on).

1963paul
Joined: Sat 19 Jul, 2014 14:19
Posts: 81

  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 31 Jul, 2017 18:34

Ok, fitted the new (2nd hand MAF), now then, I'm hoping someone will say you need to drive it a few miles for the ECU to re-program, as I just came back from a short drive ( my tea was ready before I left)! and it was still pinking a little bit, not a lot, just a bit on the last leg up the steep hill, into my drive, up to then, it was fine, floored it on the dual carriageway, found the rev-limiter again, ( so nice), OK around town, just the last 100 yards or so up the hill, about 5 miles....please someone say "you need at least 6 miles under the wheels before it all settles in"

therealdb1
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Mon 31 Jul, 2017 22:05

Sorry Paul I cannot put you out of your misery. My new (2nd hand MAF) worked straight out of the jiffy bag it arrived in!
I still think the temperature thing is a bit of a red herring. If your engine was coked up I could see how a higher temperature could pre-ignite the fuel but I still feel that this is an ignition control issue.
I cannot pinpoint where in the closed electronic loop the problem is but since you are reaching the rev limiter it sounds like the ECU is advancing the ignition ok.
As I have said before I would have changed the knock sensors by now :wink:

1963paul
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Tue 01 Aug, 2017 19:10

:head: :head: :head: :head:
Have a guess :bawl:

I'm off on holiday for 2 weeks from Sunday, no time to try again ( knock sensors, independent BMW garage diagnostics), till after I come back from Florida :sunny :sunny

Thanks everyone for all your input, really appreciated. :cheers

1963paul
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 04 Sep, 2017 12:11

Right, back from holiday, now for an update.
I have booked the car for a diagnostic check at a local independent BMW specialist (Paddock Motors, Nr Exeter). They did say it's a rather unusual fault, and it might just need a software update, but there diagnostic machine should pick up ANY issues, so, roll-on 20th September, fingers crossed.

therealdb1
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Mon 04 Sep, 2017 14:47

All right for some! :D
I hope Florida lived up to expectations.

1963paul
Joined: Sat 19 Jul, 2014 14:19
Posts: 81

  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by 1963paul » Mon 04 Sep, 2017 15:40

After 6 visits to Florida, I have never had a bad holiday there,but saying that, USA in general is always a good holiday, driving over there is a pleasure, customer service is 2nd to none, the climate, the food,it's all good, we think so anyway.

therealdb1
Joined: Tue 25 Jun, 2013 22:47
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  Z3 roadster 2.0

Re: Pinking (pre-ignition) 1999 2ltre

Post by therealdb1 » Mon 04 Sep, 2017 23:05

You should try Pennsylvania in December!
That was my last trip to the States and I got diverted from New York to Atlanta as that was the only airport recieving International flights at the time due to the East Coast being under 4 feet of snow.
We could learn a lot from from those guys. Get up early to dig the car out to drive to work, go out to the car at lunchtime and dig it out again so that there is less digging to do at home time.
We have half inch of snow in this country and the UK is closed down!
At least it wasn't a holiday and someone else was paying for me to be there :lol:

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