Miss Firing When Warm

[Simes 248 2 Cars]

I get an irritating miss-fire when warm and under load. Can only be provoked between 2-3.5k rpm and no higher which I think eliminates the ignition amp.

Going to be either the coil or leads.

 

Any other ideas?

 

EDIT - Plugs and cap are new.

Edited February 17, 2008 by Simes

[brianthemagical 1]

ignition amp would be my guess. the only way is to try tho.

[DamirGTI 342]

Ditto , I'd say either the ignition amp. or the coil try to swap/borrow the coil and amp. from good , known working car , an see if it helps

Check the dizzy signal cable also (if it's a Jetronic car) start the engine and try to wiggle/turn around/squeeze the cable a little bit ..

 

Cheers !

Damir

Edited February 17, 2008 by DamirGTI

[Simes 248 2 Cars]

Thanks,

 

Yep thought about ignition amp - I've reset that with new thermal paste but whose to say it hasn't already overheated!!

At least I think I've covered everything.

[C_W 3 1 Cars]

Rotor arm

[lagonda 42]

Only recently resolved trouble like this with mine ... it was condensation in the distributor cap!

[lagonda 42]

Should also have added ... if the problem has only occured since you've fitted new parts .... suspect the new parts! It's understandable but not a given that new parts are actually OK.

Many years ago I bought 2 brand new old stock condensers for my V12, fitted them as the originals were surely tired after 40 odd years but still worked OK. Didn't use the car for a few days & when I did it wouldn't start. Spent hours checking everything, & in the end, unbelievably, it was the new condensers. They weren't even pattern parts, but correct delco Remy ones in their original boxes! Unreal also that both were faulty, which is why I didn't suspect them immediately (car has 2 entirely independent ignition systems so will run quite happily on just one bank of cylinders).