my mates car has a slight mis on 3-4 even on revs and has no power when driven power seems to drop off
changed 1-2 ingeters to 3-4 no change
ht lead's have a spark has anyone had a problem like this
CAN ANY ONE HELP HIM

 

Had a similar problem, holed piston

Do a compression test as that will soon tell you the answer. If it is a holed piston and you need to run the engine, then unplug the injector for that cylinder, as you'll just be diluting your oil badly with fuel

 

posss head gasket between 3 and 4 or inlet manifold gasket or vacum pipe off around that area ??

 

Piston on mine caused this problem..

 

getting compression tester tomorrow

 

done compression test showing 150 psi in each one
any more thourghts

 

Check plug gaps & distributor cap, plugs could be knackered also. Suggest you try the cheap things first, if that doesn't work, change the plugs (motorcraft Series 1 RST plugs will do the job, cost around a tenner, that's what most cossie people use).

 

Spark plugs are Motorcraft 071's, finis code 1120834

 

As said do the cheapie/free things first swap plugs and injectors around to see if the problem moves with the swap, this might tell you what it is, then check co when hot.
tabetha

 

You say you have checked HT leads but have you checked 3-4 plugs for healthy spark?

Martin