2002 GMC Safari Q&A

2002 GMC Safari Question: how to fix po128 code on this van

I am trying to determine how to diagnose a PO128 error code on a 2002 GMC Safari. I would appreciate any info anyone might have on this -
Answer 1
Here's the obd code: http://www.obd-codes.com/p0128 I would suggest if the coolant level and strength are good, it is probably a bad thermostat that needs replaced. -
Comment 1
thank you.. I will try that -