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slight misfire

Posted: Mon Feb 21, 2022 8:39 pm
by Bonymaenjack
Evening
my m20 on start up from cold is showing signs of a misfire , she's starts ok but when I hold the revs steady at around 1200 the engine seems to be starved of air /fuel with the revs dropping then rising again and repeat until the engine warms up a little. Also she takes a few seconds to start ( new injectors fitted about 3,000 miles ago) any thoughts anyone?

Re: slight misfire

Posted: Sat Feb 26, 2022 7:30 pm
by BHadley
Are you using e5 regular unleaded?. I’d Change fuel filter, clean and regap plugs run on super unleaded . Had running issues years back on 318i and seemed to help.

Re: slight misfire

Posted: Sun Feb 27, 2022 9:54 pm
by Bonymaenjack
BHadley wrote:
Sat Feb 26, 2022 7:30 pm
Are you using e5 regular unleaded?. I’d Change fuel filter, clean and regap plugs run on super unleaded . Had running issues years back on 318i and seemed to help.
hi I only use super unleaded and never from a supermarket chain, so I don't think its the fuel itself

Re: slight misfire

Posted: Mon Feb 28, 2022 6:22 am
by paultv
M20 seems sensitive to distributor cap condition, I clean the posts and rotor every 3k or so, otherwise it gets noticeably more lumpy... there's a surprisingly large deposit build up even after a relatively short time, just another thing to check.

Paul :-)