Juddering/Misfire at low revs, under load

[Cnut 0]

Ever since my VR6 was taken out of storage for the winter it has been rather poorly.

 

It tends to judder and misfire when you put your foot down in a high gear at low revs (1000-2500) but it is also quite intermitant.

 

So far I have changed the coil pack which was arching - that made no difference at all. The spark plugs and ht leads which made it 80% better but still the problem is there but less pronounced than it use to be.

 

Does anyone have any suggestions as to what could be causing the problem. I have searched the threads but found no definitive answer.

 

It has also backfired once when reving the engine stationary.

 

Cheers

[iow_corrado_g60 0]

your ISV will make it run lumpy if knackered

[Cnut 0]

It might actually be related to that because it was idling like a bag of nails after storage then I got someone to clean it out and it idled perfectly again.

 

I forgot to mention that the little braided rubber pipe that connects to a pot alongside the injectors was replaced because it had a split in it and thats when all the symptons started...

[latestarter2 0]

is this ISV easy to change? mines a bit lumpy on tick over too.

[Cnut 0]

is this ISV easy to change? mines a bit lumpy on tick over too.

 

Its very easy to replace but i would try cleaning out with carb cleaner first (plenty of threads on it)

[24V Renshaw 0]

Could well be one of your injectors if the replacement of the fuel regulator pipe started the problems....

 

Whip out each of the plugs, if one is all wet with fuel then thats your problem, the injector is not misting problem.

 

Jay

[Jim 2]

Hm.. been wondering what could cause similar probs on my valver and have suspected a bad injector for some time. Thanks for that Jay.. think it answers my question.