My 1994 GMC Sierra with a 5.7 TBI has a new issue. I get a good 3-5 second delay getting oil pressure when I start up after sitting over night. After that, I have great pressure. Anyone seen this before? I am about a hair away from replacing the oil pump.

 

If its not knocking during this time,I would not worry..

remember,the oil sender gets oil pressure LAST...Of course,it could be clogged as well

 

Aye. Unfortunately it DOES knock until pressure gets built up. This is why I worry.

 

I first missed that it was a 94....Those knocked some new...But yeah,I'd probly try a pump

 

Also,make sure your using an A/c Delco pf1218 on that K motor.

 

Only A/C delco oil filter?

 

I bought it 14 months ago and only recently noticed this issue.

 

the `1218 has a check-valve to prevent the oil from draining back over night

 

So do the K&N oil filters.

 

I did not realize that the other filters did not have a check valve. Thanks a million guys.