Oil pressure low at idle
 

Hi -
I had someone pull off my oil pan to reseal it, and since he put it back on, the oil pressure bottoms out at idle, then goes up and down. At speeds above idle, the oil pressure is fine. We have already replaced the oil pump hoping to resolve the problem, but the problem remains. I did not have any oil pressure issues before he took the pan off.

My truck is a 94.5 PSD.

Anyone seen this before??

Thanks in advance!

Mike

Have you checked the oil pressure with a test gauge? A piece of grit from the gasket replacement may have found it's way into the sending unit. If the oil pressure is actually low, it may be from a split in the pick-up tube or a poor seal where it attaches.

Or gunk in the pick-up screen itself.

Thanks for the input. THe guy working on my truck called and told me that the front over (houses the oil pump, HPOP, pickup tube) had a crack in it. I am wondering if he cracked it when removing my pan, but I have no way to prove. The front cover is about $200.00 - does this sound right? Also, why would oil pressure drop if there was a crack? Would oil be leaking back down into the pan? There was no oil leaking back outside the enging, accroding to him.

Anyway - thanks again for your input!

You lose oil pressure because the tube is on the suction side of the oil pump, and with the crack it draws both air and oil. Less oil, less oil pressure. Depending on the location of the split, sometimes you can overfill the crankcase with oil and regain oil pressure. This is to assist with diagnostics and not recommended for normal operation.