QuestionHi Roland thank you on my last request, you told it perfectly. heater resistor on 1995 cirrus. it was a piece of cake with your explanation... new problem, fixed service engine lite and 2 codes came up 21 and 32, problem is 21, according to parts dept there are 3 o2 sensors, code 21 says most likely bad sensorand to replace it, (Which one)the ones in exhaust man or the one in catalitic converter, code 32 EGR. car is running well,so what does syptoms of EGR do.is it possible o2 sensor can cause the egr code. and is there 1 or more of them to find.YOU DA MAN. had last issue resolved in 45 monutes with YOUR HELP. thank you again
AnswerHi Gerry,
On the 2.5L V-6 as used in the Cirrus (but not as in the Sebring) I believe there are only 2 oxygen sensors, one on the front exhaust manifold, one after the converter. I'd suspect the upstream sensor first because it is exposed to higher temps and more pollutants. But look over the wires on the downstream sensor just to be sure nothing is broken there.
The automatically controller EGR evaluation, that is the way a 32 gets set, involves a comparison of the two oxygen sensor readings with and without the EGR in play. So I believe the 32 could follow as a consequence of the O2 problem. You could replace the upstream sensor, then erase the codes by disconnecting the battery for a few minutes, which will cause a new code 12 (battery disconnected recently). Then run the car for awhile, check the codes and then if the 21 code is gone but the 32 remains then the EGR needs some servicing. I would begin by lubricating the valve's stem with WD-40 while you lever it up and down with the blade of a flat screwdriver inserted in the slot of the stem. Often the problem with an EGR is the stem gets sticky in its action which will cause rough idle, no start, or hesitation under full throttle accelertions.
So go back to the parts dept. and verify that there is really only 1 upstream sensor on your '95 Cirrus.
Roland
P.S. Thanks for the positive feedback
