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slight miss fire on deceleration
axle - 19/5/25 at 04:13 PM

Hi all clever Clog

I have used Ford 2L DOHC 8V with the original fuel injection on my Locost . It runs fine and sounds however I do get slight miss fire after high speed on deceleration there is only very little adjustment on the mixture and the pressure valve is temper proof. Any ideas what can be done please help!!

gremlin1234 - 19/5/25 at 05:32 PM

my guess is, the biggest change from standard will be the exhaust system

axle - 19/5/25 at 05:41 PM

yes I could agree with you but how this effect it, please explain?

jacko - 19/5/25 at 06:09 PM

Different back pressure to a Ford exhaust
But it could be there is I leak on one of the exhaust joints , or a crack in the manifold

adithorp - 19/5/25 at 07:30 PM

In 40+ years of repairing cars I don't think I've ever experience a deceleration misfire.

jacko - 19/5/25 at 07:34 PM

Sorry I miss read your post you said miss fire I was thinking back fire

gremlin1234 - 21/5/25 at 07:57 PM

quote:
Originally posted by axle
Does it make any sense if I was to say as the car slowing down the misfire happen when I brake!?

only time I can think of, where braking might cause a misfire is:

cars with a vacuum servo for braking

axle - 23/5/25 at 12:53 PM

quote:
Originally posted by gremlin1234
quote:
Originally posted by axle
Does it make any sense if I was to say as the car slowing down the misfire happen when I brake!?

only time I can think of, where braking might cause a misfire is:

cars with a vacuum servo for braking


Thanks for your reply , no servo on the car . It does happen on hard throttle once the throttle is relived the misfire happens!!!

jacko - 23/5/25 at 04:15 PM

Could it be spark plugs or coils ?
Or plug leads ?

axle - 24/5/25 at 05:23 PM

Hi all
Spark plugs , ignition lead & coil + rotor all renewed previously. All sorted a lot of trial & error frustrating road test sensitive adjustment on the CO did the trick.