Running and starting issue

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JagsK1981
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Post Thu Jul 05, 2018 8:26 pm

Hi

Wondering if someone can help with this one. Just rebuilt the engine and the car starts no problem. After it’s reached peak temperature it starts to misfire and cut out refusing to restart until cold again. I was advised it may be a coil which I have changed but still same issue.

Any ideas or have you had this issue?

Thanks in advance[/list]
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arrisbmw
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Post Fri Jul 06, 2018 8:21 am

blue temp sensor.
plugs , rotor arm , distrbutor .
some things to check first.

fuel pressure could be an issue.
when it does not start if you spary easy start in throttle body , does it than start ?
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martauto
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Post Fri Jul 06, 2018 2:37 pm

May need a few more details here like car, engine, year, etc to really help you mate.

Mart.
Only the E46 cab left now.
Just got too old.
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JagsK1981
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Post Sun Jul 08, 2018 1:30 pm

Haven’t sprayed easy start as yet, I’m going to change the temp sensor today and will check
Got a new fuel pump too so hopefully its irons out this issue

My car is a 1988 325i sport auto. Engine is m20b25
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JagsK1981
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Post Mon Jul 09, 2018 11:04 pm

Hi

I’ve put a new fuel pump in and has made a difference, not missing anymore. The idle now fluctuates between 900rpm-1300rpm.

Any ideas why it could be doing this?
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arrisbmw
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Post Tue Jul 10, 2018 10:39 pm

YEP . THE ICV idle control valve , probably needs a clean. or you could have a vacuum leak somewhere on the inlet side.
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JagsK1981
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Post Fri Jul 13, 2018 1:18 am

Could it be the throttle position sensor?
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JagsK1981
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Post Fri Jul 13, 2018 6:50 pm

arrisbmw wrote:YEP . THE ICV idle control valve , probably needs a clean. or you could have a vacuum leak somewhere on the inlet side.

I have cleaned this made a small difference
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paultv
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Post Fri Jul 13, 2018 7:09 pm

Check the resistance of the blue temp sensor at the ecu both cold and hot, can't remember the PIN numbers off hand, but this will indicate if there is a problem with the sensor and cabling.

Paul :-)

Found it, look under intake, blue plug in the wiki gives pins and expected resistance.
4th May 1990 325i Convertible.

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https://bmwe30cabriolet-wdm.blogspot.com/
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Connieblau
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Post Sun Jul 15, 2018 9:15 pm

I have spent some months now (320i convertible) looking at the usual fuel pressure/ idle valve/ change this, test voltage on that. Etc etc, and I found a post on Pelican Parts where a very frustrated chap had been writing in, asking all the standard stuff and over time he had changed ALL the possible bits and he had spent quite some money doing it. He eventually had a private contact with some experience of E 30’s and the answer turns out to be the white DME (fuel supply) relay that lives with two orange relays under a little black plastic cover above the air intake ducting. Mine has just cost me about £10 and takes a couple of minutes to exchange. A relay has a printed circuit inside which has soldered connections. With age, the solder can crack apart and the tiny fracture ”˜moves’ with different temperatures causing hap-hazard symptoms. The white DME relay (with different part no’s) can be found in loads of cars (Volvo included) even Modern X5’s.
Worked for me too!
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JagsK1981
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Post Wed Jul 25, 2018 10:53 pm

Thank you so much will check these out