Need Help Deciphering Codes
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From: Fort Wayne, Indiana
Need Help Deciphering Codes My girlfriends 3.4L '99 Grand Am is throwing 3 codes, PO135: Heater Performance Sensor 1, PO141: Heater Performance Sensor 2, and P1733: Insufficient Switching Sensor 1.
What do these mean?? Heater Performance Sensor...does that have something to do with the heater core? And the last one I just have no idea. We think one if not both of the O2's are going out, so maybe these have something to do with that. Any answers?
What do these mean?? Heater Performance Sensor...does that have something to do with the heater core? And the last one I just have no idea. We think one if not both of the O2's are going out, so maybe these have something to do with that. Any answers?
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It might be bad sensors, it might not be. You should run the diagnostic troubleshooting table for those codes to confirm.
Since you have codes for both O2s heaters you might have a problem in the circuit for the heaters.
The insufficient switching could be a leaking injector, bad MAF, vacuum leak. All that is saying is that it is running lean or rich on that bank most of the time. Or it is staying rich or lean longer than the PCM has programmed for it to.
Since you have codes for both O2s heaters you might have a problem in the circuit for the heaters.
The insufficient switching could be a leaking injector, bad MAF, vacuum leak. All that is saying is that it is running lean or rich on that bank most of the time. Or it is staying rich or lean longer than the PCM has programmed for it to.
