Does anyone have any suggestions on what would help out on the Nitrogen readings of a Drive Clean test? I've heard super-test gas and drive it until the engine is very warm before testing. I just failed and want to redo the test and wondered if anyone had any remedies they have found or heard were successful in passing the drive clean. Thanks.

Using a high octane super unleaded gasoline should definitely help. Go through a couple of tankfuls before re-testing. Run the car for 15 minutes driving (not idling) time before the test. It would also be helpful to get an oil change and a tune up to set the proper ignition timing. This should help you pass.

Thanks Gerry for responding. I just had an oil change and have only went through 1/2 tank of hi-test gas. Tune up may be more costly than the drive clean repairs but I'll try the other suggestions. Thanks.