I have a 1987 T2.

It seems to have extremely high pressure, around the 110 psi marker when I get it anywhere close to 3000 rpm, but when I let off it goes back down to about 60psi. When I'm Iding it goes down to about ~35psi (~900rpm).

I have no clue why this is happening but here is what I have done up to this point.



A week ago I replaced my oil with Castrol GTX 10W-30 (Unique Anti-Sludge Formula). And replaced my filter with a FRAM oil filter.



It's been running fine (pressure wise) and so I was trying to fix my idle problem today. I warmed her up then took the intercooler off and adjusted my TPS thinking this was the problem and, Viola! I got it to stop idleing at about 500-600 and now it is at about 800 - 1000 range. So I was so happy I decided to take her out for a test drive to see if this new setting would stick. I boosted around some corners and got the revolutions up to about 7000. Then I noticed that my pressure was hitting 110psi and I immediately stopped goofing around. If I'm in 5th at 45mph my Oil Pressure is about 75psi. This is very high for my normal conditions.

Questions:

1. What usually causes high oil pressure and

2. Does this have anything to do with the Castrol Unique Anti-Sludge Formula oil I put in last week?

3. Is this possibly just a clogged oil filter?

4. Could my oil pressure sensor be going bad? (I doubt this...)

PLEASE HELP ME!!! Thank you.

 

Forgot to add that I checked my oil and it is clean and full. SO I REALLY HAVE NO IDEA. Thinking about just going to the auto store to buy another filter just to see if that's it. This time no cheapy FRAM though.

 

Ok so I put on a new PureOne oil filter and this is what it does. When I go in first gear the oil pressure is at like 60psi then if I push it so I'm getting boost it goes up to about 100-105psi. It does this in every gear. Starts about 60psi then goes to about 100 while in boost. I came to a complete stop at my house and it slowly dropped to about 32psi... so it might have got a little better but I still think this is way too high.

I read that the norm is 43-86 in my owners manual. So why would my oil pressure be lower than the lowest norm and higher than the highest norm.

WHAT IS WRONG WITH MY CAR!!

I'm starting to think it may be my sensor.

 

I can't believe you put a FRAM in your car.

That said, I'd try to find a mechanical oil pressure gauge and confirm the odd readings before getting too worked up about it. Also, make sure the connection to the sender is clean.

-=Russ=-

 

^^^ agreed. Yeah, those numbers seem to run parallel to normal numbers, just higher.

 

Hey where is the oil pressure sending unit located in the engine. I couldn't find it in the FSM...

 

It's a brass cylinder (often black with oil and dirt) on the driver's side of the engine, on the rear iron under the oil filter.

There's a single wire going to it.

-=Russ=-

 

thanks

 

why not run mazda filters?
clogged oil passage? a sad regulator? inaccurate gauge?

 

I guess I'll just find a guage to see if this reading is right and then I'll tell you guys what I get.