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turbo84gn
03-17-2012, 10:22 PM
Okay. This is my Dad's 87. Aftermarket chip. Car runs and drives fine. Check Engine Light works but is not on. Recently TurboLink was giving goofy data, saying codes are set, etc. After trying several things I started to think the interface cable is bad. And of course you can't get those anymore. Couldn't compare to my '84 because it's half apart at the moment.

Anyway, Dad decides to finally invest in a scanmaster. I hooked it up. Key on - engine not running, scanmaster behaves fine. I can scroll through data, etc. I start the car, I get the "2.1" display for a second then nothing. Dead. Zilch. Only time I can get data is key on engine not running. I connected it to the orange wire at the ALDL port. I still have 12V with it running.

Could this be an issue with the ECM? Car runs just fine, which is what bothers me. Any ideas?

Keller
03-17-2012, 11:06 PM
1) With the TurboLink issue: Have you had TL working on this machine before? If not (or even if so) settings for that port and such have to be right for it to work. You didn't mention the version, either.

2) With the Scanmaster: Did you connect power to the orange wire? That is the ECM's power wire. While it is powered all the time, the way you connected it may have the power "bouncing", thus resetting the Scanmaster.

I think we need more details regarding your connections for Scanmaster, as well as the PC setup for TurboLink.

kenmosher
03-18-2012, 09:03 AM
To add to what Scott is saying … it almost sounds like the alternator or something is causing a bunch of noise. I've seen alcohol system pumps and other electric motor things do that … whenever they are running they make hash out of the data output.

Another thing to look for is bad grounds on the back of the head. Loose/bad grounds can do that too.