lumpy idle on 325i

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eltel
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Post Sun Nov 05, 2006 1:06 pm

hi there...just fitted a new recond head on my 325i..all runs well, no leaks,no ticks ,nice and quiet and very fast...the only thing wrong is when at idle she is a bit lumpy..it's not searching it sits nicely at 850rpm but listening through the exhaust you can hear a .."putt putt putt" noise..but only at idle. the recon company say to check valve clearances after a few hundred miles when all bedded in. could these be causeing the "putting" and lumpy idle. am sure it's not the idle control valve as was fine befor and i cleaned during the recent job.

thanks for any advice
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Brianmoooore
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Post Sun Nov 05, 2006 7:05 pm

Leaking inlet manifold gasket would cause a lumpy idle, or another possibility that I've seen before is a plug damaged as it was put in. Reset the valve clearances after a few hundred miles and check all the spark plugs look the same.
Won't be anything to do with the idle control valve, unless the idle speed is way to low.
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elvis
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Post Mon Nov 06, 2006 11:49 am

thaks brian u the man
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elvis
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Post Mon Nov 06, 2006 11:52 am

i've heard that to detect an air leak on the inlet side you should spray carb cleaner around manifold while running,,is this true...

thanks

eltel :?
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Brianmoooore
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Post Mon Nov 06, 2006 12:02 pm

I use propane gas from a plumbers blowlamp with the jet removed, but carb cleaner will do the same thing.
Engine will speed up when it gets a whiff of the gas.
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eltel
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Post Tue Nov 07, 2006 11:40 am

have used a whole 500ml tin of carb cleaner all around inlet manifold and air breathers and hoses etc but nothing??

spark plugs are brand new and all ok
.
could the valve clearances cause it?
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Brianmoooore
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Post Tue Nov 07, 2006 10:27 pm

Could be a good idea to check the valve clearances now. One could be a bit tight for some reason, and you don't want to burn out a new valve seat.
old_skool
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Post Tue Nov 07, 2006 10:31 pm

I use propane gas from a plumbers blowlamp with the jet removed, but carb cleaner will do the same thing.
Engine will speed up when it gets a whiff of the gas.
8O

Just don't be 'freeing up de erb' at the same time mon :cool:

:teehee: