Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Does your engine have DOD or AFM?
If so, cylinder 7 is an AFM cylinder, and sounds like it is permanently disabled.
Quite common for roller lifters to spin in the guides, then the cylinder is in permanent AFM mode.
How many miles on this engine now?
Was the warning for low pressure or low level?
Do you need any further help?
I hope my advice has been of assistance to you.
Have you had any success with your problem?
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