Hello Ford Fans.
Could someone advise what could be the reason why the engine is running on 3 cylinders at idle? As I remember, if I hold the engine at 2000 rpm it's starts to work on all cylinders, but when returning to idle speed starts to work on 3 cylinders again. Here are two vids from first start after engine block rebuild.





(202 block, std/std polished crank, new 91.5 pistons (wiseco) with new rings (set every 120deg.). I did not rebuild the head, but before the compression was same on every cylinder. There are new spark plugs 071's (did not check the spark gap), new marelli phase sensor inside distributor with gap set to 0,2mm, new champion leads, new crank position sensor with gap 1mm from pulley teeth, coil is marelli grpA)

Tommorow I'll try to check the timing again, the compression on every cylinder and the spark on every plug.

Maybe watching vids you can guess what is the problem?
Is it something with ignition? or with injectors? (fuel pressure on rail is ok) or maybe it's the "zero" compression on some cylinder?
Thank you for any help!

 

I'm willing to bet it's one of your new o71 spark plugs mate mines did it when I fitted them don't think you can get good ones now. I've got denso ik27's maybe give them a try. Easy way to test it is swap the no firing spark plug to a new cylinder and see if it stops firing there.

 

make sure you have not plugged the iscv plug onto one of the injectors its easy done

 

thanks for replies. Adam-M is right. I've put old NGK plugs and engine started to work on all cylinders. I found a Motorcraft AGPR901C but do not know what they are worth.


Are these Denso IK27 good for standard engine?

 

AGPR901C are the equiv of ik24 IIRC

 

Well mines is just over 300bhp and stu at motorsport developments recommended the ik27's when I was in for mapping as the ngks I temporarily fitted to replace the dud 071's didn't have a high enough heat rating and risked melting the tips.

I'm sure they will be fine up to 500hp, glad you've sorted it now anyway mate