QuestionQUESTION: This is on 96 Sebring conv. that you helped me with last year when I had a problem accelerating. Finally solved it by replacing distributor and crankshaft sensor. I live in Mexico and have not had much success with the Chrysler dealership here, so I depend on learning everything I can online before I turn a mechanic loose to work on it. I had the transmission rebuilt about 3 years ago (and it was still no good until I made him change solenoid), but I didn't drive it for much of the last year because of trying to solve the acceleration problem.
It is a 2.5 motor and automatic transmission. I do a lot of stop and start driving, some of it on very dusty roads.
This week I noticed it being slow in upshifting. It would shift smoothly, but at a little higher speed than normal. This morning, when engine was cold, it shifted fine with no problems but after about 30 minutes it started again slow shifting. I mean it didn't want to shift out of low, but when i gunned it a little it shifted smoothly. It was a low on transmission fluid, and rather than just adding, I changed filter and fluid. It was time to anyway. Have not seen any leaks under the car. The car does exhaust a gray smoke at times, but not all the time. don't know if that could be related or not. Changing fluid and filter did not solve problem. Also today it started idling at about 2000 to 2200 RPM. After tapping the pedal a few times, it dropped to 1000 and would surge back and forth to 1200 RPM. Any ideas?
Thanks
ANSWER: Do the fault code using the ignition key:"on-off-on-off-on and leave on" in 5 seconds or less elapsed time. Then watch the check engine light to see it flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat to be sure of an accurate set of flash counts. Then tell me what they are in the order of appearance. This will tell us what might be wrong with the engine control, but not the transmission which you would have to have readout via the socket under the dash and a code reader.
Roland
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QUESTION: The check engine light doesn't work (as well as odometer and gear display), but I borrowed a CanOBD2 Diagnostic Tool and it shows 4 codes;
(1)P0123"Throttle Position Sensor A Circuit High Input"
(2)P0112 "Intake Air Temperature Sensor 1 Low Input"
(3) P1490 "Low Speed Fan control relay circuit"
(4)P1496 "5 volt supply output too low"
Can you translate those into laymans language for me?
Thanks
ANSWER: Hi Doug,
There are several problems here:
The 5V supply is used by the Throttle position sensor for proper operation, and also by the manifold absolute pressure sensor and the A/C pressure sensor. I suspect that the wire (violet/white from pin 61 of the pcm) to those three sensors has a short to ground or that one of the sensors has an internal short to ground. So find those three sensors and unplug them and also unplug the multiwire plug at the pcm that has that wire on pin 61. Then measure the resistance to ground of the pcm pin wire to see if it is close to 0 ohms, and if so then look along the harnesses that go to the sensors for a place where the insulation may be burned through. If the wire isn't shorted to ground then measure the resistance to ground of the pins on the sensors to which that wire is attached to see if one of them is shorted to ground. On the TPS it is pin 3, on the MAP it is on pin B and on the pressure sensor it is on pin B. The TPS is on rear side of the throttle body, the MAP is on the tranmission side of the intake manifold on the flat end of the manifold closer to the front of the car, and the A/C pressure sensor is mounted in a metal A/C tube directly behind the alternator.
The low speed fan issue may just be the relay so try switching that relay with the high speed fan relay and see if the behavior of the fans changes such that the low speed not works but not the high speed which would tell you that relay was no good. Otherwise we'll have to check the wiring for the relay circuit. The relays are hidden in the rear of the under the hood fuse box, down a level, sort of underneath the air intake hose.
I think if you find the reason for the 5v supply being dragged down the idling and running problems will go away.
Roland
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QUESTION: Roland, thank you for your succinct easy to understand answer. I can find those sensors, but on the pcm, i don't know how the pins are numbered or how to find pin 61, pin 3, or pin 8 and I can't find a diagram. Where do you start counting?
AnswerI believe if you look on either the pin side or the wire side you will find the numbers to be engraved. One plug is 1-40 the other is 41-80. 61 will be on the outer edge of pins in any case so you can tell which of those 8 pins has a wire with the colors you are seeking. Same with the other plugs I mentioned. By the way it is a B not an 8 that you are seeking on the 3-pin plugs that have letters rather than numbers. B would be the middle pin as would 2.
