Auto 3.0l stalling at traffic lights when pulling away

[zedebee]

When throttle is pressed the revs. drop before rising and engine stops - most embarrassing! This only happens occasionally not all the time. It is unpredictable. Can anyone suggest a remedy, preferably DIY? Thanks for looking.

[ynysmeudwy]

I had this problem with my 2.8 and when I took it to the local BMW specialist it was a couple os sensors that needed replacing (Done under warranty)

[mich]

When throttle is pressed the revs. drop before rising and engine stops - most embarrassing! This only happens occasionally not all the time. It is unpredictable. Can anyone suggest a remedy, preferably DIY? Thanks for looking.

Hi zedebee, did you get the problem solved?? I have experienced the same thing with my 3.0i 2002, not life threatening but embarrassing, if it is a sensor it would probable be on the fuel supply? Please keep us informed

[varboy]

I have had a similar problem when chaging from reverse to drive or vice versa. If I don't give the engine chance to build revs (about 1 sec) then it stalls.

Very embarassing especially as people like to think that other people with nice cars can't drive.

[zedebee]

Here is the reply I received from BMW UK.

'Thank you for providing the vehicle details, we can confirm that there are
no inherent faults on the vehicle.

To elevate any further concerns you may have, we would recommend you contact your local BMW Dealership so they can look into this further'.

Note the 'elevate' - was it a really a spelling error?

The unpredictable nature of this fault is now beginning to annoy me!

So here I go, I will book my car in this week to get it fixed and I will let you know the outcome. (and brace myself for the bill! - of course I may be pleasantly surprised, but I doubt it!)

[mich]

Hi Zedebee, The stock answer to these things are always the same
ie. Very isolated, almost unheard of, this is the first one we have had reported etc etc, but from the bits I have picked up on these forums it is not uncommon, I wonder if there is a conecting link?? say dampness getting into senser conections, or infrequent use???
Just thinking out loud, looking forward to your report.

still cant get this spell check to weeeerk

[zedebee]

Job done. BMW main dealer diagnosed and replaced pulse generator on inlet camshaft. Took just over an hour at a cost of - Diagnosis £35 + Sensor £60 + Labour £ 41 = Total of £136 inc. VAT.

Now ticks over at about 650 rpm ie lower than before and seems more responsive/smoother. Worth it to know that I shouls not be embarrassed at the traffic lights again - famous last words!

Would be interesting to know the outcome and costs of yours for comparison?

Good luck - Clive

[mich]

Hope it lasts, am now making tracks for local BMW Dealer,
Thanks for info and PM. Have sent you PM

[mich]

OK. I had the Z fixed Yesterday, Just as you say. The Camshaft sensor.
Throtle much more responsive. especialy at the lower end, have to be very carefull now pulling away from the lights. Cost was about the same $380NZ. I had it explained thus:
Engine system = 3 systems. 1= BRAIN, 2= Lower eng system (crankshaft etc), 3= Upper eng system(Camshaft etc). Brain recieves wrong signal from Upper system and doesnot know what to do, so it hesitates or at worst does nothing.
Perhaps someone can give a more enlightened and detailed explanation.
Any way it all rings a bell somewhere so I off to my GP to-morrow

[Yella]

Well had I read the string earlier would have been able to tell you it was the camshaft sensor as mine was exactly the same, now fixed for £85 the car is like you said much more responsive and much more even when accelerating

[lakelandhiker]

From reading the posts on stalling it sounds like my camshaft sensor also needs replacing - common problem on Z3's???? Is this a DIY job or does the car need plugged in to a computer to tell it the sensor has been replaced?

David
(z3 3.0)

[mich]

From reading the posts on stalling it sounds like my camshaft sensor also needs replacing - common problem on Z3's???? Is this a DIY job or does the car need plugged in to a computer to tell it the sensor has been replaced?

David
(z3 3.0)

Get a quote for labour first, it is only a few minutes to fix say 20-30 min max
not worth the trouble of DIY, providing you trust your garage

[AndyBass]

Replacing the camshaft sensor is an easy DIY job, but you should visit a dealer, or indie if you want the fault code re-setting. I was told the car will run OK it'll just have the fault code stored. The sensor's job is to talk to the ECU and tell it what position the camshaft is in in relation to the crankshaft. There is one for each camshaft on a double vanos engine. Basically the timing of both cams is altered to give good low down torque whilst keeping power strong at the top end of the revs, something not easily achieved without variable timing. You either get one or the other. The sensors tell the ECU to alter the position of the camshaft via hydraulic pressure and the camshaft(s) timing is both retarded and advanced as the revs rise. Thats why they pull from idle so well.

[lakelandhiker]

Cheers for the technical info Andy. Its nice to know how these things work.