320 m20 engine esitates on power

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gcmog
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Post Thu Feb 07, 2013 10:26 pm

Hi can anybody help with a problem i have with my 1988 320i.Intermittant lack of power , holding itself back & slight misfire. I have fitted new plugs & leads , new coil ,new intake hoses , removed & had the injectors checked, new inlet manifold gaskets & fuel hoses. I have had the fuel pump out of the tank & all seems ok. Getting a bit fed up now, can anybody help . :mad:
Quaser
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Post Thu Feb 07, 2013 10:35 pm

timing?

does it happen when its cold/hot - could be the blue or brown temp sensors

could also be crankshaft sensor
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Speedtouch
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Post Thu Feb 07, 2013 10:37 pm

Have you checked the distributor cap and rotor arm?

Also worth changing the fuel filter, if it hasn't been done in yonks, as a clogged one will be restricting the fuel flow.

How many miles has it done? Could be worth carrying out a compression test to ensure all six pots are reading roughly equal pressures.
///M aurice
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Grrrmachine
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Post Fri Feb 08, 2013 6:34 am

Is this all the way through the rev range, or just at lower revs?
mcbonio
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Post Fri Feb 08, 2013 9:08 am

Sounds like an ignition issue, check dizzy cap and rotor arm.
Grrrmachine
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Post Fri Feb 08, 2013 10:57 am

Also, if your "new" leads were aftermarket ones consider switching back to the originals. General consensus is that non-BMW leads aren't good enough in the long term,
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gcmog
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Post Sat Feb 09, 2013 9:39 pm

Hi all, thanks for your replies .The rotor arm & dizzy are good , but it does feel more like fuel starvation , it is at its worst below 2000rpm but still feels like it is holding back all the way the rev range. I put a new in-line filter in it a couple of months ago.I removed the fuel pump out of the tank again today & checked ,seems ok & pumps what looks like ample fuel & holds pressure in the system.I have re-checked the timing & thats ok.The poor old girl is trying my patience slowly , because the fault isn't always there , or disappears if you stop & re-start some times.She has done 189000 now , but has been a reliable motor for the past 14 years.It has also developed a little hicup on tick over.All suggestions will be well appreciated.cheers
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Post Sat Feb 09, 2013 9:42 pm

I would suggest a compression test as the next step - all six cylinders should be giving roughly equal readings of 170 psi or more.
///M aurice
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gcmog
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Post Sun Feb 10, 2013 9:35 pm

yeh , thanks for the suggestion , i'll get it sorted this week & let you know the outcome. cheers.