my oil pressure guage has been jumping around for awhile. when i put the clutch in the pressure guage work but as soon as I dissengage it goes up pass 400(metric) and stay there... what is the problem?

thanks

 

Loose hanging wire underneath?

 

I checked for that? nothing...

 

Having a problem with your description:

When you engage (let off the clutch pedal) transmission (i.e. engine/tranny connected)- you oil pressure is correct or 'pegged'?

 

when I let out the clutch the oil pressure is pegged past 400.. but it some times jumps around but not often.. gota be a sensor or something?? does anyone know where to look...

 

The oil pressure sensor is located just above the oil filter, on the block. It's real easy to break.
Buy a new one.

 

This could be the problem OR ......it might be the sending unit .......it's a one piece looks like a big filter ........on my 86 it's behind the d-cap on the intake right against the fire wall ......i think i paid $35 for a new one at crappy tire .

Mark

 

^^^ True, true.

Replacing both won't break the bank, and it sounds like good insurance to me.

The problem with malfunctioning oil pressure gauges is that in the future, you may not be able to discern between a gauge/sensor problem, and an actual pressure problem.

 

Sending unit's have always been a big problem in these cars .

Just FYI ......Jon's right ....won't hurt to change both......it's a pretty important issue .....oil presure

Mark

 

Before you swap parts- you should probably verify that the connectors on the sensor(s) aren't just a bit loose or corroded.

Fact is, when you let the clutch out- even if you're not in gear- drivetrain vibration goes up- so a flakey connector might be cutting in/out of electrical contact.

Also- not knowing what you're driving- if you had a CCC-carb'd vehicle with A/C- alot of the sensors are connected- i.e. if power steering sensor cut in to indicate that it was under load (i.e. at one steering extreme or the other) it would cut the A/C out to reduce engine strain. If I recall- the electric choke wire and oil pressure sensor (for light) were also connected so that if oil pressure fell too low electric choke would cut off and hopefully stop engine running. The point is- check all connectors on the related systems for looseness/corrosion before swapping parts.