Hey

I just bought a 1990 IROC-Z (350/700R4)... The Oil Pressure Guage moves back and forth a lot. The guy I bought it from said that his mechanic said it just needed a new oil sending unit... Could this be possible?

-Thanks

 

yes.

 

Could be. Or you could just get a whole new mechanical oil pressure guage since GM factory gauges are junk.

 

Okay, after examining the situation a little more... I found out that the gauge doesn't really move back and forth a lot... it just seems to be low. My last car ('88 IROC) had a Jasper 355 and it's Oil Pressure was at like 40 at idle and like 60 when driving. This car (the '90 IROC) idles at like 15 and goes to 30 while driving? Is that TOO LOW? Should I go ahead and put in a new Oil Sending Unit and see if that helps?

-Thanks

 

YES!

 

My 305 has worked like that for ages. It isn't "spec" but will still run fine. If you're worried, use a little heavier oil like 10W40, 15W40 or even 50 weight.

 

Sounds like the sending unit. It is pretty common for them to read low when they get old. It is above the oil filter and really not that hard to replace.

 

You could replace the oil pump first, like I did, and then do the easy job (sending unit ) last .