New poster here, thanks in advance for the help!
The computer in my dad's 1998 5.7L Express Van flaked out (wouldn't read MAF). We changed it with a new one that is correctly coded for his VIN, and we did the security re-learn process, so it starts and runs great. But, the check-engine light is lit because the computer wants a CASE Learn to be performed. The problem is that each time I start the CASE Learn process and raise the RPM, the speedometer twitches (comes off it's post briefly) and the CASE Learn fails because the computer thinks the truck is moving.
The speedometer does this "twitch" whenever the RPM is raised to around 3-4000. It shows you're moving 5 mph and then settles back down. Anyone have any idea what would cause this? The truck is in Park with the brake held, so it's definitely not moving.
I wouldn't care about the check engine light, since the truck runs great. But, the truck won't pass state emissions testing with the check engine light lit. Is there any way to code tune out the CASE Learn code so that the check engine light doesn't come on?