Help :( Idle issue

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deevo90
E30 Zone Newbie
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Joined: Thu May 30, 2013 11:00 pm

Post Fri May 31, 2013 11:40 pm

Hey guys, I appreciate if anyone could help with this.
When cold my car seems to have a rough idle. It sounds as if the engine is choking itself. As the engine is turned on the revs drops and the engine nearly dies(engine shaking) but then kicks itself back into life by slightly revving up and does the same over and over again for around 5 minutes. If I touch the accelerator whilst doing this the car will completely die, when the revs drop back down only way to keep it going is to keep revving it. When the car is warm there isn’t any issue with the performance. I recently changed the spark plugs ad I noticed one of the distributor leads has been taped by the previous owner. (D.I.Y job)

1990 316i.

Would be so thankful of an help.

Niall.
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Brianmoooore
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Post Sat Jun 01, 2013 12:03 am

Welcome to the zone!
I doubt if the taped up lead is anything to do with your problem directly, but it might be indicative of the type of (poor) care the car has received in its previous ownership.
Start your quest by testing the coolant (commonly known as the blue) sensor at the socket of the engine ECU, with the engine hot and cold, then move on to testing the throttle position switch.
Check whether the CO adjustment pot on the air flow meter and the throttle butterfly stop on the throttle body show any signs of having been meddled with, and resist any temptation to do so. They were set correctly at the factory, and do not need adjustment.
Testing methods are all in the zone wiki, and if you need any further explanation, ask back on this thread.
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deevo90
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Post Sat Jun 01, 2013 12:15 am

thanks il keep you posted!
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deevo90
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Post Sat Jun 01, 2013 12:26 am

capri_rob
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Post Sat Jun 01, 2013 6:48 am

Yep thats the one
Image

e30topless said : Proper BMW's have 4 headlights, last of the run was the E30 and E34/E32 anything after that is just complete shite
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deevo90
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Post Sat Jun 01, 2013 7:31 am

thanks guys!
Grrrmachine
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Post Sat Jun 01, 2013 9:23 am

I'm presuming that between 12:15am and 12:26am you managed to test the coolant sensor, which is why you're looking for a replacement. If that's not the case, DON'T just buy a new sensor and fit it - TEST FIRST.
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Brianmoooore
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Post Sat Jun 01, 2013 9:43 am

TEST THE ONE YOU HAVE!!!! Don't start randomly replacing parts - this is a) expensive, and b) you are very likely to introduce faults that you didn't have in the first place.