overfueling

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shane30
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Post Thu Apr 15, 2010 9:12 pm

hello all i am new to this forum have just brought myself a e30 325i sport with a bit of a running problem just wondering if anyone could help me out a bit please.
it seems to be running rich on idle and hesitate when throttle first pressed down but when driving runs smooth. here a list of thing i have already checked:
-Air leaks (now has none)
-air flow meter
-Valve Clearances
-Compression (all at 130psi is this alright) been told slightly low
-Timing
-New spark plugs
-new HT leads
-New rotor Arm
think that's about as far as i have got, any help would be very grateful thanks
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steviec_lj
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Post Thu Apr 15, 2010 9:42 pm

Dude, first of all, you really need to change your avatar. Its massively oversized.

People may then be able to help you as they will be able to read your post.
shane30
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Post Thu Apr 15, 2010 10:26 pm

sorry mate was trying to figure out if i could just make it smaller but will just get rid of it for now.
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aeberbach
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Post Thu Apr 15, 2010 11:15 pm

Make sure nobody has "upgraded" the injectors with those 19lb jobs from eBay.
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b17
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Post Thu Apr 15, 2010 11:56 pm

Mine has similar issues but I think I've traced it to a dodgy ICV. How do you know it's running rich?
clipper
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Post Fri Apr 16, 2010 10:48 am

Interesting that you say the engine has no air leaks NOW. This suggests that you have repaired a leak ?

Are you sure that someone in the past hasn't messed with idle mixtures to "fix" (mask the effects of) an air leak which is now repaired ?

This is what happened to me, the mixture screw on the AFM had been wound right in, a quick trip to exhaust analyser and a tweek of the AFM mixture screw and all my rich idle problems disappeared.
These are sensations as hard to forget as they are to ignore.....
shane30
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Post Sun Apr 18, 2010 11:45 am

thanks for all your help, where is the mixture adjusment on one of these likely to be is it the allen key bolt in the air flow meter thanks again
kman82
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Post Sun Apr 18, 2010 11:53 am

Yes thats the one. My rich idle was sorted with a new blue temp sensor, i tested the resistance on the old and it didn't seem that far off what it should be but a replacement sensor sorted everything!
Grrrmachine
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Post Sun Apr 18, 2010 12:03 pm

DON'T TOUCH THE MIXTURE SCREW! You need to have a gaz analyzer up the exhaust to make adjustments; random twiddling will only make things worse.
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N00b
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Post Sun Apr 18, 2010 12:12 pm

kman82 wrote:Yes thats the one. My rich idle was sorted with a new blue temp sensor, i tested the resistance on the old and it didn't seem that far off what it should be but a replacement sensor sorted everything!
This is what sorted mine out as well. TBH I didn't even bother testing the old one as a new sensor from the dealer was only around £20.
shane30
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Post Tue May 25, 2010 2:37 am

ok have got round to doin a bit more to it finally. have changed the temp sensor tested the wiring down by the ecu for the sensor, checked cam and crank timing only thing i can find out of place on the engine side of things is that there is what would seem to be a knock sensor or summin like that just hangin around by the crank pully looks like a blot should pass thought it the bolt to the block but cant find anywhere for it to bolt to. also i have a friend with a 325i but his has a bigger throttle body then the one on my 325i would this be to do with the high and low compression heads that are used

thanks
kman82
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Post Tue May 25, 2010 8:52 am

Does the sensor you mentioned look something like this?

Image

The one shown in the picture is actually an ABS sensor but from memory they look similar. If it is it bolts onto the timing case and points towards the vibration damper on the crank.
(Vibration damper is labeled in this pic)

Image

It fixes with an allen key bolt to the left hand side of that picture (Drivers side)

Hope that helps
shane30
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Post Wed May 26, 2010 9:32 am

um no i have the crank angle sensor bolt up in place to the sensor ring on the crank pulley but i have another wire that goes round from the diagontics port to the drivers side of the engine and looks like a really small placstic dounut probs the best way to describe it and just has a wire cumin off it. look like a subaru impreza knock sensor is another way to describe it. thanks for ya help tho m8.
shane30
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Post Mon Jun 07, 2010 12:36 am

thanks would this affect the way it would run because I have traced the wires back to the 3 pin plug under the diagnostics plug then goes into the diagnostics plugs in the engine compartment?
thanks