3.9 EFI tickover problem

Hi,

I have just done both head gaskets on my 90 3.9 EFI V8, it runs fine from cold but when it gets up to temperature it starts hunting almost to the point of cutting out. It revs up and drives great but just wont tickover when warm.

It was running well before i did the head gaskets (appart from losing water).

Any help would be greatly appreciated.

did you fit new manifold gaskets?

Yep, new manifold gaskets

You got LPG?

No LPG

If the engine is hunting it could be a problem with any of the following:

Idle air by-pass valve (stepper motor)
ECU
Coolant thermistor
Stretched timing chain

Air flow meter could be a factor; do you have an EFI warning light? does it come on?

If you do a search you will find just about everything you need to kow about rough running and idle problems. Good luck.

All sorted, it was a problem with the distributor. The centrifugal advance baseplate was bent and the springs were loose. Fitted a second hand dizzy from ebay and shes now running great.

chappers90V8 said:

All sorted, it was a problem with the distributor. The centrifugal advance baseplate was bent and the springs were loose.

Click to expand...

MMMMMM....... that's an interesting one. Certainly makes sense but can't say I've heard that one before. How did the base plate get bent? Anyway, glad you got it sorted.

Not sure, the base was bent and both pins that secure the springs were damaged and the rubber blanking plug in the side was missing. I did find a piece from a distributor cap inside the bottom end of the dizzy, it was the centre contactor that touches the rotor arm, maybe this caused the damage. Thanks for your help