Oil pressure gauge needle off zero

[manco989]

Started my car (04 GXP) and the oil pressure shot up to over 120psi after the gauge did its check turned the car off and noticed the gauge stopped at 40psi instead of zero tryed a couple more times and same thing the needle wont go under 40psi even during checks gauge idles just under 120psi and does react to Throttle. Any ideas and i know its a gxp but i figured this is related to all Bonnies

[RJolly87]

If it doesn't sweep low to high like the rest of the gauges, it's likely the stepper motor has failed for that gauge. Very common problem for that generation. And if one failed, it's likely the others aren't too far behind it, which will be something to bear in mind when it comes to repairing.

You can either replace the cluster, send it off to have it repaired, or repair the cluster yourself (requires circuit board level work, with disassembly and soldering).

There is a very comprehensive guide to this posted somewhere on the forum about going over the cluster, or you can contact Harofreak00 to see if he has any good units in stock. He also has done the repairs in the past, which, if he still does, may be another avenue worth pursuing.

[manco989]

It sweeps but just kinda stops where it wants ill see how this goes probably be hitting up harofreak for a new one soon

[RJolly87]

Some of the oil sender units have been known to go bad as well, and when they fail, they tend to peg max, but can also have a mind of their own. Is it possible to upload a video of the dash on a gauge sweep, and then start up? Just to verify it is the cluster.

[manco989]

Ill try to get a video today had my sending unit changed last year under warranty

[nos4blood70]

Since it responds to throttle input, I think it's the cluster's stepper motor. If it were the sensor, it would likely peg after performing the normal sweep.

[ddalder]

When you turn the car off, one of the functions of the cluster is to return all the needles to full left deflection. The PCM does not continue to transmit oil pressure information and nothing will be reflected in needle readings. This is not a case where the sender is connected to the gauge. Everything is done electronically through the data bus. These gauges will act erratically when the gears inside start to wear and bind. There is virtually no doubt in my mind, based on what you describe, that the stepper motor is defective. A couple of my stepper motors were bad. One minute I had no oil pressure, the next it worked fine except that the needle didn't return to zero when I shut the car off.