IM CAT test incomplete

2002 Camaro Z28 (5.7L LS1)

Please help restore my sanity. For six months I have been trying to get the obd2 internal monitor to run the catalytic converter test. I live in the Peoples’ Republic of California, so it’s important.

What I have done…

I have done countless “drive cycles”
Replaced input air temp sensor
Replaced air filter
Cleaned MAF sensor
Replaced all four O2 sensors
(I only have about 75 miles on it since I replaced the O2’s)

DOES ANYONE KNOW what exactly has to go right in order for the computer to run the tests? I would dearly love to see a flow chart.

Help, please, help!


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I have found that turning off the A/C as mentioned in @Tester attachment is usually what gets missed on GM vehicles. Can verify that it is a critical step.

What’s your driving style when performing these drive cycles?

Are you smooth and steady?

Or racing from stop light to stop light and passing everybody like they were standing still on the freeway?

The former is the way to go, in my experience

Please don’t get upset that I asked

All I’m asking for is information and clarification

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