isakpede

Hi.

I have some problems with my oil pressure readings on my 1994 GTS. Sometimes it just drops dead while driving and then come back after a while. Sometimes it is dead when I start the car and comes back after driving a while.

• The pressure sensor is changed.

• The original electrical connector on the oil pressure transmitter has been removed and New Connectors fitted

• All three whires has been measured to be OK from the sensor all the way through the 14 pin Connector in the engine bay, through the main electrical Circuit board up to the instrument cluster.

• The low oil pressure warning light is tested OK (Third wire)

Any ideas? Could it be the instrument cluster or just the oil pressure gauge?


Isak

Wisconsin Joe

Does the light below the gauge come on?

Does the CWL come on?

If neither come on, then it's most likely the gauge.

If you've kept running it with the gauge at zero and the engine didn't seize, it's the gauge.

And when I say "the gauge", I mean that the gauge isn't reading right. That behavior sounds like wiring in the cluster or pod.

My temp gauge has done the same thing for a while. My fuel gauge just started doing it.

I can sometimes make them work or not work by adjusting the pod up and down. I'm beginning to suspect a broken wire (inside the insulation), in the wiring that goes to the cluster.

There are writeups on pod/cluster removal. Dwayne's is the one I like best.
You will have to find the one that tells how to remove the pod without removing the steering wheel.There are a couple out there.

I missed that you have an airbag car. Duh.

Randy V

Try raising the pod up and down with the engine running and then report back with the results.

daveo90s4

You can use the digital dash diagnostics to report oil pressure too. That will report oil pressure readings bypassing the analogue gauge.

isakpede

Thanks,

Could I do this with a Durametric Enthusiast Version?

FredR

You have a discontinuity problem somewhere- possibly on a soldered joint that makes or breaks on mechanical shocks going over bumps or whatever. My gauge does something similar, you either have to live with it or trace it. Given what you have written I would be suspicious around the connector strip on the back of the cluster.

I find it reassuring to see the oil pressure gauge needle moving irrespective of how accurate it is [or is not] but the fact is without oil pressure the motor will last about what- 30 seconds?

Instrumentation can cause more problems than it solves when it is wonky. My tach signal often goes loopy at about 5200 rpm- did on both my 928's. I do not know what causes that problem, it irks me but at least I know the electronic systems will cut out the motor to prevent over revving as long as the system is working- so do we really need a tachometer?

If you see no oil pressure on the gauge and you also get a low oil pressure alarm signal in tandem then you cut the motor as quick as you can no matter what.

Regards

Fred

Schocki

The low oil pressure warning on the pod display will only show up if the idiot ligh tis triggered. As previously mentioned, it is good idea to get into the self diagnostic mode to see an independent reading.

Common failure is the ground solder spot on the instrument itself. What you are describing was like my oil pressure gauge in 2005. Removed the instrument panel (search for 15 minute instrument pod removal). Open the cluster in the back and remove the bulb circuit board. With this you have easy access to the instruments. Re-solder all ground points, done.
This is also a perfect time to either replace all most used light bulbs (like the "D") or convert to LED and catapult your interior light to this century.

No idea why it is in 99% of all cases the oil pressure gauge itself, but this is what you can expect to see on the backside of the instrument...

isakpede

Tried raising and lowering the pod, did not change anything.

isakpede

Thanks Shocki.

I have read one of Your treads regarding this matter earlier and forgot to mention in my intial post that I have been out with the instrument cluster, changed all bulbs and resoldered all joints on the instrument board. The only thing I did not resolder, was the ground point of the instrument itself, which will be the next thing on the agenda.

I'll get back to you!

ROG100

Same thing happened on my GTS and I was lucky to have Schocki close by. He re-soldered the joint and never been an issue since.

Tony

similar kind of issue many times with the PRND32 lights in the console not illuminating...one of the circuits has discontinuity on the board. Took me ages to track that one down.

isakpede

Hi.
I took out the instrument cluster today and resoldered the ground connections on all the potensiometers and took the car for a testdrive.
After 70 km, there where no signs of oil pressure drop out. Thank you for the tip Shocki.

But, I notised that my instrument lights where dimmed once I switched the head light button to both step one and two. The dimmer was set to the highest level, but it still lit half as bright as when the head light button was switched off.
According to the owners manual the instrument lights should be automaticly adjusted when the head light switch is off.

I have to mention that I have installed a daylight relay in position III.

Any ideas?

Schocki

This is normal as the cluster assumes it is dark. Mine does exactly the same. The instrument lights should be very easy on your eyes as soon as it is dark. They are still dimable with the headlights on.
The on board diagnostics allow you to check the photo optical sensor in the cluster.

Good to hear that your oil pressure is working again 👍

isakpede

Is this possible to do with a Durametric Enthusiast version?

Schocki

Sorry, but what is " Durametric Enthusiast version"?