EGR or Cat. converter(s)? - Ford Forums

SeaBass · 06-12-2004, 21:10

Hello,
I have a 94 crown vic w/100,000 miles. It recently started hesitating/stumbling on light acceleration particularly uphill. When I bought it 6000 miles ago it had a code for the egr posistion sensor. The car ran perfect but the eng light came on alot and my mileage was 19-20 highway so I swapped it (pfe sensor) with a known good sensor for trouble shooting.

It then gave a code for the valve not opening all the way and the light came on less. It still ran like a brand new engine.

Since it started hesitating I've replaced the air and fuel filters. The exhaust smells rich to me. With the (new sensor) I get a 332 and 337 code.

With the old I get a sensor out of limit code during the key on eng off but no running codes.

The vac to the evr is good. (I swapped this with a known good as well to no effect). The vac to the egr valve(from the evr) briefly rises to 15 or so during the key on eng off test. When I apply vac to the egr valve with the engine running the rpm changes and the diaphram hold vacuum.

There is a pulsating vac at the pfe sensor but it's not much.

It seems like all the components are working... but I still get the 332 and 337.
or 335 with the old. Swapping evr's and pfe's has no effect on the stumble.

If I floor it I think it might be pinging, there is definitely some odd noise.

Could I have a clogged cat? (dual exhaust) Could the evaporative canister or solenoid do this. I did have trouble filling it today. The pump would kick off early and not fill it. I went to another station and it worked fine though.

Any help would be appreciated!!!

SeaBass · 06-13-2004, 10:19

No techs out there that want to take a stab at this one??

amo4387622 · 06-13-2004, 13:11

Does this only happen on light accel or does it also happen when driving highway?

SeaBass · 06-13-2004, 20:43

Once I get up to 73 I set the cruise. If it's still happenning then it isn't noticeable.
With the O.D. off it is still present but not as bad I suppose due to the higher rpm. Between 50 and 60 is where it's worst.

amo4387622 · 06-13-2004, 21:32

With my knowledge of Crown Vics you have one of these or all of them a dirty MAF sensor, carbon under air inlet and a bad spark plug wire. Make sure you get the carbon cleaned out of the manifold- intake area. And runnign a cleaning solvent through the engine really wont get rid of the carbon either. But if u want to try to use a cleaning solvent use seafoam i have hard it works really good from people that use it.

SeaBass · 06-16-2004, 09:15

Well, I cleaned the MAF, sucked a can of seafoam through the intake, and took it out for a good hard drive. It seemed a little better, but once I got it on the interstate it was worse than ever. When it got dark I sprayed the wires and they were arcing all over. New plugs and wires and she purrs like a kitten. Thanks for the help.

amo4387622 · 06-16-2004, 10:03

Glad to hear the car is purring like a kitten.