03 envoy oil pressure issues

[lithanedr]

Oil pressure Guage drops to near zero the shoots back up to 60-65. It is sparatic at best. No engine noise when this does happen. Oil is full and needs changed soon as it has 2300 miles on the oil. I run high mileage Castrol 5-30 as specified. Any help would be great.

[Doug_Scott]

I would get a mechanical oil pressure gauge and test the oil pressure with it. It would be best to try to get a T fitting and run both mechanical gauge and factory gauge at the same time to prove to yourself it is not the engine, but likely the sending unit.

If a new sending unit is under $20 I would swap it first, if cost is higher than that, I would do the testing first.