zero oil pressure at start up

[Riche]

1997 K1500 130,000
zero oil pressure at start up, followed by a little lifter noise that goes away. How many of your guys get this?
My truck never did it till I changed the oil with a carquest filter. then it started. I went back and got a Delco thinking there was a check valve in it and the problem is still there. Dose anyone have any ideas? Maybe I have a Delco filter that doesn't have a check valve? If there are different filters is there a way to separate them?? I would hate to screw up my motor b/c some car parts store is selling old filters!!!! I would appreciate any advice.

Thanks,
Richard

[mbumgua]

Sounds like could be bad or plugged sending unit for gauge--often goes out after oil change- sludge in sending unit? Maybe. If no oil pressure computer shuts off fuel pump. usually two sending units for oil pressure--one for comp. and one for gauge.

[Riche]

I only have zero pressure for a few seconds then it jumps up and everything is good. I know what a motor sounds like with low oil and that is the sounds that it makes till the pressure jumps up.
I just wish I knew if there is a way to tell if I am getting the right filter. I like to stick with the old rule of what what the last thing you did before it all messed up!!!!!
I am not over looking the oil pressure sending unit. but if that was bad wouldn't my truck run rough with the fuel pump not pumping?

[nosefirst]

Originally Posted by Riche

I only have zero pressure for a few seconds then it jumps up and everything is good. I know what a motor sounds like with low oil and that is the sounds that it makes till the pressure jumps up.
I just wish I knew if there is a way to tell if I am getting the right filter. I like to stick with the old rule of what what the last thing you did before it all messed up!!!!!
I am not over looking the oil pressure sending unit. but if that was bad wouldn't my truck run rough with the fuel pump not pumping?

I'd be using an addtive if I were you. How much oil does your rig burn? I'd be monitoring your compression too.

The additive will help reduce any accelerated wear during the timeof 0 preasure.

If your burning oil and your compresion is on the low side all around, your engine might be worn out.

[Riche]

If it is burning oil, it can't be much. all my plugs look good and no smoke. I have a catalytic converter code on bank 1 that probably has nothing to do with this though.

[nosefirst]

Originally Posted by Riche

If it is burning oil, it can't be much. all my plugs look good and no smoke. I have a catalytic converter code on bank 1 that probably has nothing to do with this though.

The pick-up hangs down into the oil pool and I seem to remember a friend of mines comming loose or getting cock-eyed or something.

That would be an easy fix. Not exactly what I'd be looking forward to this weekend.

I'd still be putting an addative in there untill you figure it out. You know, something real sticky that will stay on your cylindar walls etc. after you shut down. I can't think of the name of that stuff. You probably know what I mean.

Good Luck.

[mbumgua]

Usually two sending units for oil pressure--one for computer at back of distributer and one for gauge by left side exhaust manifold on block. The one for the computer controls the fuel pump.

[Riche]

"Usually two sending units for oil pressure--one for computer at back of distributer and one for gauge by left side exhaust manifold on block. The one for the computer controls the fuel pump."

Thanks for the heads up. Have you seen this happen before? I don't see how a fuel pres. could make that tapping noise. and then go away as my gauge comes up. Would that give my truck a little stumble at hwy speed? I need to get a diagnostic scan tool bad....

[Snowgoer05]

What kind of oil are you using because it sound liek tis a cheap oil quality and when you switched filters did you use same oil and just curios what brand of oil so i know not to use my friend had a problem just like it is it a thick oil like 15w 50 or is it 5w 30 or what try changing to the opposite of a thick oil thats probally what you did try 5w 30 with it and partial sythetic get the good stuff