QuestionHi, I have a 94 Spirit 2.5L. I recently changed a leaking heater core, and also made some repairs to leaking fuel lines. Now, the gas level gauge is not working properly. When the car is shut off, the gas hand is in the "normal" position, but when key is turned ahead (and when running) the gas hand moves in a clock-wise direction (away from the normal direction) and stays at about the 9 o'clock position. All of the other gauges in the instrument cluster work fine. I am guess this is a wiring problem. Any advice would be a great help.
I also have one other problem. When the car is warmed up and the car comes to an idle (~800 RPM) in Drive, the oil pressure gauge drops rapidly. When accelerator is pressed and the tach reads about 1000 RPM, the oil pressure guage returns to normal. This was occuring before the heater core replacement. In neutral there isn't a pressure gauge problem either. Any help on this matter would be greatly appreciated as well.
Thank you
AnswerHi Trevor,
On the fuel gauge, one thing to consider is whether you might be using fuel with increased alcohol content which has the potential for faulty level reading unless a special gauge unit was installen in the car. Leaving that aside, the possibility that the sending unit is defective is the first thing to check. You will find a 3-pin connector at the tank, and if you disconnect it and ground the dark blue wire at that point it should cause a full scale reading. If you ground the light blue/black it will cause the low fuel warning light to go on. Ungrounding the leads should conversely cause the fuel gauge to read empty, and the light to go off, respectively. Then read the resistance between the dark blue- and the black/light green- connected pins of the sender unit's socket. After driving off a quarter more of the fuel in the tank see if the resistance has risen as it should do. It should read 0 to 8 ohms with the tank full and 100 to 112 ohms with the tank empty. If far off from that spec or inverted, then replacing the sending unit is the cure.
On the oil pressure, it could be the sending unit resistance is out of calibration. It too has a low pressure warning light. I would not be too concerned about the gauge reading but you could check to see if it's resistance between the pin for the gray/yellow wire and the unit's metal shell case is 30 to 55 ohms with the engine running and infinite ohms with the engine off. If you want to verify what the pressure really is at idle in gear you will have to substitute a calibrated pressure gauge for the sending unit (located near the oil filter) and verify that idle pressure is at least 4 psi, and that pressure is 25-80 psi at 3,000 rpm. Also verify that the oil pressure warning light is on when the ignition is on but the engine isn't running.
Let me know if this doesn't help you get started on solving your questions.
Roland
