Ok, I have a '94 Jeep Grand Cherokee and the engine light came on yesterday. I tested it using a OBD scan tool that I have and it gives me the trouble code #52. Using the included software and Haynes manual it says "Oxygen sensor signal input indicates rich air/fuel ratio condition during engine operation." Question is, what are the possible causes that would be triggering this code. I have done extensive searching on the internet with no help. I also did testing using a digital multimeter on the MAP sensor, the Air Charge Temperature sensor, and the Throttle Position sensor(TPS) and all were within limits EXCEPT the TPS. It was off just a fraction in the voltage allowed but that should send it's own signal, shouldn't it? I have not checked the O2 sensor yet but will, that is suppsed to throw it's own signal too I thought.
2007-10-17 10:23:13 · 3 answers · asked by msdz2000 4 in Cars & Transportation ➔ Car Makes ➔ Jeep
The other day when it was raining the "Check Engine" light went out and has not came back on yet. I was told that the MAP sensor can detect outside temperature and humity and sends signals to the PCm to adjust the fuel/air mixture accordingly, is that true? Also, the Jeep has a hesitation when it takes off from a dead stop only and only on days that seem like it is hot and dry. Since the weather has already started changing that is not as often now.
AND it is DEFINITELY code 52 that was coming on, I used my code reader AND also did the manual check that can be done by checking the flashes and pauses with the engine light.
2007-10-20 14:40:37 · update #1
the tps could cause the pcm to think the throttle is open further than it really is, adjusting injector pulsewidth to compensate. but... the 02 would see the rich condition, the idle would suffer and the idle air controller would open to compensate. all technical discussion aside, you need to check the 02 sensors output voltage while running. backprobe the output and make sure you're not getting over 1 volt and that it dances from about 200mV to 800mV at a high enough rate that your DVOM has a hard time keeping up with it. If you get a steady voltage, chances are the 02 sensor is shorted inside to either the ref. B+ or the heater B+. If it's not switching and the voltage is high, unplug it and check for voltage in the signal wire of the harness. could be a wiring issue before the 02 as well.
2007-10-19 08:34:34 · answer #1 · answered by Anonymous · 2⤊ 0⤋
I can't find this code for jeep. I don't know how you came up with it. However the code is indicating a rich mixture when engine is runnimg. This would indicate possibly a leaking fuel injector or not enough air (possibly fault in tps) I suppose you know that the throttle has no function on fuel rate. It only admits air to the engine and the ecm calculates the correct fuel mix. The code you retrieved may be wrong. I would go to auto zone or similar auto supply and get another scan. If you turned the mil off wait till it comes back on. This is not a faulty O2 sensor code. The tps usually doesn't have it's own code. You didn't mention any other faults like hesitation or rough idle or such.
2007-10-17 11:34:36 · answer #2 · answered by tronary 7 · 0⤊ 1⤋
i've got are available in the time of this till now. no longer on a Jeep, yet on yet another motor vehicle. Leaves and stuff plugged up the heater middle. This stopped the fan from pushing air in the process the heater. nevertheless felt warmth, it in simple terms did no longer blow. except you're very available and don't strategies getting grimy, you will could take it someplace. A exterior guy ought to try this for you because it relatively is in simple terms time eating. no longer a rather technical factor. attempt asking on Craigslist for cellular mechs on your community.
2016-10-04 01:08:52 · answer #3 · answered by ridder 4 · 0⤊ 0⤋