Ive tried to swap coils and no matter what coil I put in the # 2 cylinder it does not spark at low rpm. I started tracing the wires and have found no breaks. Any ideas what would cause this ? Ecu ?

 

So after swapping a coil it still stays at #2, then you need to swap the power stages, a little more of pain in the butt. It should move to another cylinder, if it does than you need a new power stage, if it remains, then you need to check for an intake gasket leak, and do a compression test.

DanR '94 964 358,000 miles (124,000 on the new engine)

 

Yes after swapping # two stays out.. What is this power stage you speak of ? and where is it and whats it look like ?

 

The power stages time the spark pulse with the coils, there are two, one facing forward controls the 1, 3 and 5 cylinder and the rear facing one the even numbers. Locate on the bulbous part of the intake, just under the throttle body, the rear one may be easier to reach from under the car.

Swap those and see if it moves to an odd number cylinder. If it does change than you need to get new power stage, if it stays there on number 2, then a compression test to rule out a damaged valve, you could have an intake gasket leak at number two, or you have a bad fuel injector.

DanR

 

# two sparks.. Did a compression test and # 2 has 50 psi at idle.. 140 when rev it up. I put a new head on over the winter so I think the rings are shot. Gonna run it till it blows.