[Gamikatsu]

I just bought a 94 Formula/TA and it had a Completely rebuilt engine, trans, and new stage 1 clutch, (all had 2900 miles on it when i bought it). also had new tires, rims, and more....

1st issue...
my problem... at startup, 50+ psi oil pressure, at hot idle, after warming up, 25 or so PSI. and never tops out past 40 or so PSI, regardless of 2000 rpms or 5000 rpms. 40 psi is fine for me on that... (yes i know 10psi per 1k rpms, but i'm assuming the release spring is popping into effect at that point.

after driving it a bit, either hard or softly, at idle the oil pressure is bouncing from 20 psi to 0, and check gauge light comes on... i'm assuming bad sending switch... 0 oil pressure would indicate shot bearings, and the machine shop that rebuilt it, is more than reputable, they are the premier engine shop for a long time... and the block they used was a Jester Longblock.

the guy i bought the car from, said the oil pressure had been doing that since the rebuild... and never worried about it. I personally don't like it, and want to fix it... anyone have any other ideas?

2nd issue...
When the above happens... and the PSI starts dropping to zero... my power steering just stops working... unless i rev the engine a hair... 1100 rpms keeps the steering working, and the oil press up... i'm curious at what the heck is going on....

Thanks!!!
Ed.

 

[Injuneer]

What grade oil are you running? Have you checked the oil for a fuel smell, possibly resulting from the engine running excessively rich?

25psi hot at idle (should idle at 800rpm with the 6-speed) isn't bad at all. I'd be concerned about the 40psi upper limit. The stock relief spring will allow 60psi.

As far as the gauge readings, could be the sending unit or sending unit wires shorting out. If it was an intermittent open circuit, the oil gauge would be pegging at 80psi. Does the pressure drop mainly when you are slowing down/stopping? That would indicate the oil pump pickup has fallen off. Put a mechanical gauge on it to check the sending unit.

 

[Gamikatsu]

I'm guessing a faulty sending unit reading 10-20 psi low... i don't have a mechanical gauge or else i would. I gotta head over to the local autozone and see if they rent one out....is there a trick to getting a intake mounted pressure sending unit off? my oil weight is 10-30 high mileage according to previous owner... full of oil on the dipstick.

 

[Injuneer]

The early 94's had the sending unit right above the oil filter, the later 94's had the sending unit at the top/back of the block, just past the edge of the intake manifold. If your sending unit is on the top, maybe these pics will help you figure out how to remove it: (Courtesy of Shoebox)

You can hook your mechanical gauge to the port right above the oil filter. I have a mechanical oil pressure gauge in the dash, and its connected in that location:

 

[Gamikatsu]

Well i believe i have both problems figured out...

i did a full oil change to Mobil1 10/30 synthetic with synthetic lucas oil stabilizer and a mobil1 filter... oil pressure is 1000% more stabil now. and hte power steering issue... the pump is shot, its full of small brass flecks in the fluid and started whining really bad last night. i'm going to install a mechanical oil pressure gauge and run it to the dash somewhere so i know whats going on in my engine, it appears that my Console cluster is going bad, the speedo is off 5mph , the Odo doesn't work right, andthe only thing that really seems to be on par is the Temperature, and the Tach... i dont' know if i even trust my fuel gauge... oh well. the power steering pump is ordered, and i'm looking for a donor 94 firebird/transam donor vehicle for a cluster. Thanks all!!!

 

[Injuneer]

Oil pressure is the one on the right..... with the bad reflection.

 

[Gamikatsu]

ok... the Aux 1/4" NPT oil passage port had no oil leaking from it when i pulled the plug out... any reason why?

 

[joesperformance]

Oil pressure is the one on the right..... with the bad reflection.

I love how u did those gauges, its exactly what I am wanting to do with my aftermarket gauges, but how did u route the wires? do u still have a/c and heat? How did u bypass those ducts, so its not beating on the back of the gauges? you can shoot me a PM if you want.