Low oil pressure and engine knocking

Hi,

I'm hoping you auto experts can give me some advise.

I have a 2002 Gmc Savanna with only 65,OOO miles on it. It was consuming coolant in which I had a mechanic replace the head gasket. I also had it tuned up and the water pump replaced. I never saw coolant in the oil, it was being burned up, and/or leaked out.

Since the work was done in in March, I have had issues with the check engine light. No one can read it because the computer is "not communicating" with the tool.

Now, I also have very little oil pressure... 20psi or less. I am developing a knock in the motor which is very noticeable while stopped and idling in drive. When I changed the oil, I had a lot of crap on the drain plug.

Please note, I have been very meticulous with maintenance on my van. I change my oil/filter monthly. The oil has always looked good up until after this work was done.

My question is: What did this guy do to my van? Is it possible he left some left over gasket or whatever in the motor to clog up the oil pump? Any ideas? How does this happen in less than 2 months? What should I do?

I appreciate any advise. Thanks!

George

Welcome to aAF, no way to answer this without removing the pan checking the bearings and pump to see what what is worn/damaged. Typically if coolant gets in the oil for any period of time it will damage the bearings. Unless debris was carelessy allowed to get down in the enine during the repair process can't see what the mechanic could do wrong here.