DanielRicany

Hello everyone. My oil pressure usually reads between 20-30 on a hot idle. Yesterday the oil pressure was abnormally reading 45 ish at idle. I attached a mechanical oil pressure gauge to the port for the oil temperature sensor. When the engine got hot, the dash was reading 10-15 PSI higher than the mechanical gauge, so I suspect that I have an issue with an inaccurate digital gauge.

I recently replaced the oil pressure sensor a few months ago, so I am a bit skeptical in condemning the oil pressure sensor. Is there usually any common issues with the wiring or dash cluster itself before I go deeper into my diagnosis?

Thank you.

WVZR-1

You could check the sender for Ω, a very popular replacement is spec'd @

0-3 PSI = 0-5Ω,

7 PSI = 13 - 26Ω

60 PSI = 58 - 83Ω

80 PSI = 70 - 105Ω

You can see the very wide +/-

I believe the earlier FSM only mentions for the gauge 3 - 90Ω (variable running). See maybe 8A-142 and close. I don't think an '85 had #'d cells.

KEY-ON CHECK (NOT RUNNING)

A later FSM for the same diagnostics will mention I believe disconnected the GAUGE SHOULD PEG @ 80PSI (+/- 3PSI), GROUNDING the TAN WIRE with JUMPER GAUGE to 0 PSI.

Just thought I think I can "snapshot" this for you. This is '87 and uses the same sender.

DanielRicany

Thank you for that chart. I purchased some resistors and was able to use the chart to diagnose it as a bad sensor.

WVZR-1

Sender replaced and fixed? If the sender was from a "local" AP I'd think a warranty replacement at just a few months.

DanielRicany

I'm not even going to bother getting a warranty replacement. I'm just going to get another brand all together. It's cheap enough and I don't want to risk having this happen again.