Weird Oil PSI in TA

['02 ws6]

Ok, I replaced the sending unit about a month ago after my FAST 92 swap, and now the oil pressure is doing the same thing it was doing with my previous unit. Usual idle psi is 38-40 warm.

Now when my last unit went out it started fluctuating real crazy, from 20psi @ idle, up to near 70 at 2-3k rpm, and 40psi on the hwy. After I shut the car off, and fired it back up, the guage would read -0, like a dead gauge, then after 2-3 minutes of it running it would jump back up to normal for about 5 minutes, then go back to fluctuating until I eventually turn if off. Repeat cycle.

Is there a problem with my new unit? For the month's time it's been in there, I've had no problems, and a solid 40+psi reading from idle. Now it's back to fluctuating which makes me think it's the unit again. Could it be a connection problem or something?

I thought it may be my pump (stock 65k mile), but that wouldn't explain the month's worth of good psi readings immediately after the sending unit swap, and now back to being funky.

What do ya think Charlie?

[Blackrider]

I know LS1's have an issue with the oil pickup O ring not seating correctly causing erratic pressure.

[GRRRR8]

Since it was fine for a month, I would be looking at doing a oil pressure test with a mechanical gauge and see what it says 1st as a precautionary measure then let me know.

['02 ws6]

That was my initial thought. BUT! It's all too convenient that it was fine and normal for a month IMMEDIATELY after replacing the sending unit. If it was something else, wouldn't it have been persistent even after replacing the unit?

[GRRRR8]

My guess is connection, ground or gauge issue. I just dont take a chance on oil pressure reading issues.

['02 ws6]

My guess is connection, ground or gauge issue. I just dont take a chance on oil pressure reading issues.

I don't either, but this scenario strangely coincides with the last problem.

I first thought a connection issue was going on and it was having to kind of "search" for a proper psi, or a ground problem as well, but if it was a ground connection problem, the gauge would go dead anytime it lost connection, but once it picks up, it maintains a reading until I shut the car off.

I'm going to O'Reilly tomorrow to buy some electrnics cleaner and try to clean the connector and possibly route the wires as far as I can to see if there's anything unusual going on back there, but unless you're a contortionist, it's going to be hard granted the units placement, and my TA's miniature engine compartment!:hang:

['02 ws6]

Well Charlie, bad news. I haven't even started the car all week, so today in preparation for this weekends races, I wanted to take my car to a shop in the next town to get the oil pressure checked.

Before I left I had to run to the post office......right when I pulled in and started to get out, I could hear it. Tons of valvetrain noise, as well as a faint knock in the bottom end. I drove the car home, pulled the filter, chopped it open.........yup you guessed it, a LOT of metal shavings not only in the filtered part but also in the oil drained. Looked like a Copper metallic Brown paint, pretty cool looking. So bye bye bearings, and maybe a few cam lobes, as I think the lifters collapsed in the trays and might have scarred the cam a bit. :(

On to my H/C/I build of an LQ9 6.0 shortblock I bought for $400, w/ only 45k miles!

Plan on Stg 3 6.0 or LS6 heads, with a Pat G cam, and my ported 92/92 I already have.:)

[GRRRR8]

That sux! Well it is about to be a beast thats for sure. :woohoo:

[used2vtec]

sorry about your bad luck. goodluck with the new build.

['02 ws6]

Well it was more stupidity driving it than bad luck, but I'm OK with it being my fault. On the bright side, that LS1 made TOO much valvetrain noise, I could never get the preload set right, varied from .020 up to .120. That was always a pain, plus I ran the stock rockers on my heads with bronze guides, so the guides were worn a bit as well, and I had some smoke on startup, which I've always hated.