91 Engine Noise - ZR-1 Net Registry Forums

koshe2 · 01-23-2017

I just bought a 91 ZR1 with 115K miles. 6 speed Has this knock when its cold, at engine speed. It goes away for the the most part when its warm. Does not rattle at idle, but seems to start at 2000 RPM under load. Sounds like a lifter, Injectors have been replaced at one time.

I live near St Paul MN and would like to have this checked out. I am not super worried as it calms down when warmed up. Oil pressure looks just fine.

Where do I start? Suggestions??

Not sure what oil is in it. Not sure what to uses. 10-30 mobile 1??

I am new to this forum...

01-23-2017	#1
koshe2 Join Date: Jan 2017 Location: River Falls, WI Posts: 4	91 Engine Noise I just bought a 91 ZR1 with 115K miles. 6 speed Has this knock when its cold, at engine speed. It goes away for the the most part when its warm. Does not rattle at idle, but seems to start at 2000 RPM under load. Sounds like a lifter, Injectors have been replaced at one time. I live near St Paul MN and would like to have this checked out. I am not super worried as it calms down when warmed up. Oil pressure looks just fine. Where do I start? Suggestions?? Not sure what oil is in it. Not sure what to uses. 10-30 mobile 1?? I am new to this forum...