the car runs great before the engine warms up, but after that it runs rough at any speed or rpm range, in gear, but it revs up with no hesatation or skip in nuetral or park. but when a load is on the motor it starts skipping erratically. I have changed coils, sparkplugs, cat con, O2 sensors, cam-crank-knock-temp-ect-sensors but no change switched injectors around, smoked the vacum lines what am i missing it has me puzzled, the ECM-ECU-PCM has been checked its fine also. PLEASE HELP ME IM STUMPED oh yea it has thrown a 01300-01400 code out there to which is a unknown code in any manual or guide i have access to?
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2002 Chevrolet Prizm
Question: my 2002 chevy prizm has a random misfire after it warms up at idol and any rpm
seek help and diag
Replyackmon360, August 30, 2012, 14:12Rookie
thats why im on here this is the first time i have visited these sites for help and diag the extra codes were from my checking the injector and coil pulse
Answer #2joelburke26 from Joels Auto Service, August 30, 2012, 14:38Master
did you mean p0130 and p0140 ? the first one is a o2 sensor malfunction n the second one is an o2 sensor no activity.im thinkin bad connection or broken wire(s) going to your o2 sensor.can you run a live data check with your scanner? the o2 sensors should operate between .1-1.0 volts once the engine warms up.watch the scanner.the fuel trim runs in the open loop with the engine cold.once it switches to closed loop(engine warm) thats when you should see the o2 readings fluctuate.
Replyackmon360, August 30, 2012, 16:44Rookie
No its 1400-1300 it was the coils throwing a code to the safety control in the pcm when I interrupted the pulse to them.the ho2 was .8 and the o2 was ranging from 1.4 to1.8