quick question everyone, looking at 88 iroc to but with the 5.7 TPI engine, it runs great and has 130K original miles on the car, the only problem is when the car is started the tach gets pegged at 7. Dont know if its the guage itself but the oil pressure on that same unit is at zero or sometimes climbs up to barely over the red. Is it possible that the engine actually has low oil pressure or is the oil guage messed up like the tach is. THe engine runs PERFECT and sounds beautiful.

 

heres a pic

 

mine did the same thing till i got new auto meter gauges and that fixed it hope this helps.

 

Check your oil sender. I had my old oil pressure sender fail on me at a stop light the gauge suddenly went to 0. Scared the crap out of me. The sender should be down by the oil filter and Autozone carries replacements.

 

Regarding the tach, about a month ago, mine starting doing that as soon as I shut the car off. It goes up, down then up to 7,000 as well where it will stay. The next time the car is started, within a few minutes it returns to where it belongs. Although we share the tach issue, my oil pressure gauge always works fine and when running is in the normal operating range.

 

im looking to purchase this car, so is that something i should worry about that the oil pressure actually is low or is it not worth checking, since its most likely just the sender, it has 134K original miles and owned by the original OLD lady owner.

 

If it runs without knocking and etc I would think it's just the sender. Normally very low oil pressure means other issues. Oil pressure should increase if you rev the motor. You could put a manual gauge on it if you are worried.

 

If you're serious about buying it, go buy another oil pressure sending unit and install it. I think it should be located beside the distributor. Easy to change and costs all of $20. Then you'll have a better idea of what the oil pressure is.

 

the engine runs smooth and great, no noises at all. And the oil pressure guage moves up a little above the red when you rev it, but goes to zero when its idling. The engine runs great, should i be worried about it actually being low oil pressure or is it most likely the sender.