Jerking at 4000+

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koos
E30 Zone Regular
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Location: Crawley, West Sussex

Post Sat Aug 13, 2005 4:10 pm

Had my 320 for 3 or so months and ever since it's had a bit of a jerk on acceleration from 4000 up? Bought a K&N panel filter just cos I wanted one (not to worried about the jerk) and it fixed the jerk, funny thing is the old filter was still pretty new. Strange but true. K&N's fix all-It's the miracle filter :D :D :D :D :D :D
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stevo
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Post Sat Aug 13, 2005 4:13 pm

dazleeds
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Post Sat Aug 13, 2005 4:23 pm

mmmmmm i used to get a strange jerk as u described
hasnt happend for a while tho Daz
www.oldskoolfantasy.co.uk
in the shit,the one to blame,yeh its all my fault ;)
rickk
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Post Sat Aug 13, 2005 8:40 pm

I've found that this is related to a mixture problem... If the mixture is a little too lean you'll experience exactly this - slight hesitation around 4k, for some reason, it probably needs all the fuel it can get at this point.

Had this one when I had a 2.5 bar (instead of 3) FPR, had it when injectors were clogged and noticed exactly the same when playing with AFM spring settings.

Note that the AFM will only make a difference in non-WOT situations. On WOT a predefined, slightly richer mixture will be injected - that could also be the problem: faulty TPS.