Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

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kjb1
Joined: Thu 04 Feb, 2016 11:12
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  Z3 roadster 1.9

Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

Hi all, have a 1997 P reg Z3 which is smelling like it is running rich. Symptoms are rich smell from exhaust, and to a point within the cabin.

other symptoms to this car are:

car needs a new exhaust which i am aware is 1 piece and two boxes. Could this be leaking into cab or causing poor mixture?

Temp sensor never gets out of the blue / vents have some heat although not very hot at all. sensor or genuine stat trouble?


The car idles great, and drives great, can't layabout the mpg yet as I have only owned it 1 day, but would imagine its going to be pretty poor for a 1.9 due to smell, any suggestions for the issues mentioned?

Thanks

Jon
gookah
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  Z3 roadster 2.8

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by gookah »

you havent got a pool of petrol under the filler cap due to a blocked drain have you?
That was the cause of my petrol smell at one time
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I have an element of 'M-styling' on my car, If that's a good enough reason for the manufacturers to adorn a 320 with the M badge, then its certainly a good enough reason for me..
deni2s
Joined: Mon 25 Mar, 2013 22:02
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  Z3 roadster 2.8

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by deni2s »

Check for leaks on exhaust side before the o2 sensors and read ECU errors. Replace coolant temp sensor.
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

deni2s wrote:Check for leaks on exhaust side before the o2 sensors and read ECU errors. Replace coolant temp sensor.
How many o2 sensors on the 1.9 engine? and where are they located on the exhaust?

Ive ordered a new rear silencer ( its quite long and includes an extra section ). Is it on this or further upstream?

What benefit will coolant temp sensor have if replaced? any recommendations on where to buy?

Thanks again


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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

gookah wrote:you havent got a pool of petrol under the filler cap due to a blocked drain have you?
That was the cause of my petrol smell at one time
Funnly enough, yes. I soaked it all up today, have to find something to clear it out now, something small.


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Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by Del »

99.9% certain it is a thermostat issue - very common - they stick open causing the car to run too cold. The temperature sensor acts as a "choke" and in your case is sending a message to the ECU telling it that the car is still cold (which is accurate because the coolant is too cold) and so the mixture will be enriched - hence the constant smell of fuel. So confident am I that this is your problem that I'll eat my hat if this is not the case :D

One of the first jobs I did on my 1.9.

The temperature gauge should move fairly quickly to 12 o clock and stick there regardless of outside temperature and the heater should be nice and toasty warm.
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

Del, many thanks, I've just ordered a new thermostat, so fingers crossed it is this!

I cant wait to get to a point where the car is running sweet and all my niggles are over. Can then improve the look of car.




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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

Image

here she is!!


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Southernboy
Joined: Thu 07 Oct, 2010 12:39
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  Z3 roadster 3.0i
Location: Johannesburg

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by Southernboy »

Here you go....
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"Normal is overrated"
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Z3 Upgrades and Additions
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

I have read up few things. And one member mentioned the older 1.9 twin cam which I think I have ( 97 P reg car ) has only 1 lambda sensor, upstream of cat, and only later cars which were more environmentally friendly etc had the two 02 sensors, this correct?


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Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by Del »

Yep on the UK M44 1.9 engine there is only one, pre-cat O2 sensor - towards the front, under the cover, just in front the gearbox - driver's side. Made by Bosch - they tend to be fairly trouble-free on these cars - a error code reader would normally indicate if there is a problem.
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

Del wrote:Yep on the UK M44 1.9 engine there is only one, pre-cat O2 sensor - towards the front, under the cover, just in front the gearbox - driver's side. Made by Bosch - they tend to be fairly trouble-free on these cars - a error code reader would normally indicate if there is a problem.

Thanks for the clarification del, nice one!!
deni2s
Joined: Mon 25 Mar, 2013 22:02
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  Z3 roadster 2.8

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by deni2s »

Got only one o2 sensor also on 1997 EURO 2.8 engine.
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

exhaust changed, new thermostat in place. No fuel smells now present


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Brian H
Joined: Tue 16 Dec, 2008 19:55
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  Z3 roadster 3.0i

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by Brian H »

kjb1 wrote:exhaust changed, new thermostat in place. No fuel smells now present Image


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Thermostat was my first thought, you may need to renew the oil, if you have been running like that for a while the oil will become contaminated.
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kjb1
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  Z3 roadster 1.9

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by kjb1 »

it looks / smells recent. Ihave only just picked up the car, but yes, good shout. Will look into it in near future.


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peter2b
Joined: Sat 01 Nov, 2014 18:47
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  Z3 roadster 2.2i
Location: cheshire

Re: Z3 RUNNING RICH, FUEL SMELL FROM EXHAUST....

Post by peter2b »

your new toy look good, to clear out the fuel capdrain I used a bit of coat hanger wire(1 of the 101 uses of coat hanger wire)
peter2b
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