Thread: EGR valve problems and cyclinder misfire

SES light came on the other day and engine RPMs were going haywire when accelerating hard. Anything over 2500 rpm the rpms flutter and engine starts knocking at 55 mph. Hill climbs are a trouble spot to and rpms flutter there too.

I had the codes ran and they were P1406: EGR valve pintle position circuit and P0303 cyclinder 2 misfire.

I have already replaced the EGR valve and gasket and it seemed to temporarily fix the problem.

I'm going to run seaform through the the engine tomorrow to see if that will clear up any carbon deposits there might be at the intake manifold.

Could a vacuum leak cause just one cyclinder to misfire or should i look at this as two seperate problems and look at the plugs, wires, and coils? If it is what is the best way to find a vacuum leak?

Update on the problem:

The EGR valve code is no longer...changing out the EGR valve solved that problem.


Cyclinder 2 is still misfiring though, so I changed out plugs and wires for the first time ever for the car at 150k. At first all seem to be good then she started acting up again. Losing rpm's during acceleration and what not.

Tomorrow I'm going to replace the coil pack for cylinder 2. Hopefully, that will do the trick because I'm not sure what else to look for. Any suggestions....