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View Full Version : My Lumpy Idle cured!!!



allante666
11-06-2010, 08:16 AM
I recently posted a thread on a few forums regarding my lumpy idle. I would like to thank all those who gave me ideas and suggestions, I tried all of them. However, my utmost thanks go to Nickk from uklegacy.com forum who has saved my sanity by correctly identifying my problem. It was indeed a case of closed up valve clearances. My exhaust valves had no clearance at all yet a compression test showed up all pots to be ok.
Nick gave me this bit of wisdom:-

"Regarding compression this won't show up reduced valve clearance unless it has got really bad especially as most comp tests are done cold-ish. My valve clearances once got down to about 0.03mm (should be around 0.25mm) but compressions were still as yours about 12 bar. This has previously been the cause of lumpy idle on my car, but tended to be when warm, not all the time."

Mine was like it when cold as well. Its more likely to happen in an LPG car like mine but can of course happen in a petrol one.
This was really doing my head in but not any more.

Many thanks to all who helped and particularly to my new hero Nickk!!

Huffer
11-06-2010, 09:16 AM
Update your original thread, dont start new ones. Glad the problem was fixed!