1994 LeSabre EGR Problem

[ront]

1994 Buick LeSabre
3800 engine
148,000 miles

Engine misfires/chuggles at part throttle and light load (about 60 mph). Has good acceleration/performance otherwise.
P1406 History code.
Scan tool shows EGR Actual % swings wildly when the chuggle happens but the EGR Desired is steady..
Engine runs great when EGR is unplugged.
Tried a new EGR valve and it didn't fix the problem.
Intake manifold vacuum is high and steady when EGR is disconnected.
I could use some suggestions!!!!

Thanks

[RABarrett]

If the sensor was replaced when the EGR was, the problem could be the way the ECM processes the info from the sensor. If the ECM cannot process the info, it will dither the EGR valve attempting to come to grips with the erratic info. Ray

[tman]

Dumb answer-> Leave the egr valve disconnected!

Smart Answer->get the ecm checked out.

[ront]

Originally Posted by tman2093

Dumb answer-> Leave the egr valve disconnected!

Smart Answer->get the ecm checked out.

Thanks!

I was really tempted to go with the dumb answer but I just picked up a new PCM today and will install it tomorrow. It better fix the problem or I will use the dumb answer!!!!!!!!

Ront

[tman]

if you use the dumb answer, make sure you wrap the connectors in electrical tape.

[Flatrater]

Originally Posted by RABarrett

If the sensor was replaced when the EGR was, the problem could be the way the ECM processes the info from the sensor. If the ECM cannot process the info, it will dither the EGR valve attempting to come to grips with the erratic info. Ray

What sensor are you talking about? This EGR is not a Ford EGR!!

[ront]

The new PCM took care of the problem so I don't have to go with the dumb answer.

Thanks to all that responded.

Ront