92 Toyota pickup just installed rebuilt long block. Drove fine except code 52 knock sensor and a small oil leak. Drove truck around town (no high speed highway) for the first 500 miles. Truck is now leaking oil in a few spots, but mostly passenger valve cover. Took intake off, replaced valve cover gasket again, new pcv valve, ran new wire from KS to ECM, changed oil and filter to now use 5w30. Hooked oil pressure guage up where sending unit screws in and start it up. It is idling high at around 1700rpm, but sounds good and ks code seems gone. Pressure is at 95-100 psi. All of the research I can find say likely oil pump (pressure relief valve not functioning). It has new oil pump that came with engine from folks that rebuilt it. Since replacing oil pump is an absolute pain I am wondering if there is something else likely that could be the issue? Also, if pressure relief valve is malfunctioning would that cause 95-100 psi at <2k rpm? I know it is thin oil, new, and cold, but my understanding is that isnt going to push it anywhere near that. Any suggestions of other things to check and likelihood pump us culprit.

 

I don't know specs on a 3vze, but I'd imagine at idle high 20's would be close to max psi. At 3,000 rpms 75psi is probably close to max.
When we tested oil pressure at the dealer under 10psi at idle was almost always the case, on any model.
I think removing the sender and using gauges by-passes everything else; leaving just the pump/relief valve on the table. If not the pump/valve the only other thing i can thing of is a restriction somewhere. You should contact the rebuilder and get them involved. High oil pressure can be just as damaging as low.

 

Per the FSM, spec oil pressure at 3000 rpm is 36-75psi https://web.archive.org/web/20100326...16oilpress.pdf . So you're high, but not that high.

Note also the idle spec: 4.3psi! As Jimkola mentions, a big difference.

 

Yeah, even the 1987 Supra with the straight six 7MGTE(turbo) was 4psi at idle. The needle on the gauge barely lifted off zero at idle, which always gave owners(at least those paying attention) some concern.

 

How is everything going?


 

So, got OEM Aisin pump installed over last 2 weeks. Absolute PAIN getting to this thing with engine in truck. Started truck last night...PSI 100 at high idle (around 1500 rpm). At a loss here. This block does have oil cooler that has slow oil/coolant leak so considering doing a delete on that. Any other ideas welcome.

 

Have you consulted the engine rebuilder?
With the oil pressure reading on the gauge being confirmed with a oil pressure gauge tester, and the possibility of a bad oil pump being essentially eliminated by using a oem-grade pump, I'd think the next suspect would be a restriction somewhere.
As an example, If they bearing clearances at the crankshaft were too tight that would restrict flow and raise pressure. It also would reduce flow to the heads. But many things could reduce flow.
I'd send the rebuilder an email(and print a copy), with a follow up phone call. The email is just so you have a paper trail. Start recording everything in a log with date/time/names.

 

Ok, so I called rebuilder (engine monster) and told him high oil pressure (95-100psi) with 2 different oil pumps, but the idle was high (1500 rpm). He said cannot get accurate reading with idle that high so get idle down to 5-600 then test. Even though FSM states it shouldnt get that high at 3000 rpm I thought it was enough of a test to declare high oil pressure, but he wasnt having it. What are your thoughts? I will keep truck running and work on getting idle down, but have been cutting it off pretty quickly since there was chance oil blockage somewhere.

 

I seriously recommend doing email, then calling if needed.
I believe FSM has the 3vze at 750-850 rpms at idle. 500-600 I'd think it'd be close to stalling. But 3vze owners here can correct me if that's wrong.
I follow your line of thinking regarding psi at 1,500 vs 800, but get the idle speed down. If you turn the adjusting screw clockwise that should lower it. Or is your throttle plate staying slightly open?

 

Well this is news to me, I was very concerned about such low oil pressure I added Lucas to raise it some. Now I know it was supposed to be that low at idle.

 

I think removing the sender and using gauges by-passes everything else; leaving just the pump/relief valve on the table. If not the pump/valve the only other thing i can thing of is a restriction somewhere. You should contact the rebuilder and get them involved. High oil pressure can be just as damaging as low.