[JC316]

I have an 01 Taurus with the 3.0L OHV engine and 153K miles. It had a head gasket blown, so I replaced all that and have it running good except for a rough idle.

I started out with getting PO302 and a PO301 pending code. I changed the plugs, wires, and coil first as all were bad. The coil had burned through it's casing and was arcing, it was on the cylinder 1 side. After all that, it was still missing. Next I took the fuel injectors out and they were pretty nasty so I soaked them in fuel injector cleaner and got them looking good. Put it back together and the PO302 was gone, but PO301 remained. I went and got a new fuel injector for it, installed it and the PO301 remained for a few miles, then got replaced by a PO302.

It runs great once it's above 1200RPM, it doesn't miss at all and it doesn't fire a code, just when it returns to idle does it start missing.

Any idea?

 

[izzmo]

Is it a light misfire or is it missing consistently on both cylinders every cycle?

 

[jndejure]

Did you check the throttle body and the EGR ports for clogging? Possible failure of the related sensors which can be cleaned or replaced with junk yard parts on the cheap.

 

[JC316]

Is it a light misfire or is it missing consistently on both cylinders every cycle?

It's missing on one or the other consistently. I have yet to get it to idle smooth. Rarely do they miss together.

Did you check the throttle body and the EGR ports for clogging? Possible failure of the related sensors which can be cleaned or replaced with junk yard parts on the cheap.

No, I haven't yet. I will check those today.

 

[JC316]

Checked the EGR and TB. No clogging. Also changed out the no.2 cylinder fuel injector plug and it's still missing.

 

[Jeff K]

Soaking the injectors in cleaner did little if anything to clean them up internally. If you think you have dirty injetors, you may want to have them professionally cleaned / flowed.

 

[JC316]

Bleh. The valves are burnt. 60PSI on both the number 1 and 2 cylinder.