Well, no responses to my question....maybe I wasn't specific enough or this is the wrong forum. 1995 Chevy G30 van chassis on a motorhome. 7.4 engine, auto trans. I really would like some advice. I have a 43 code which is intermittent and it is a knock sensor system code. New knock sensor made no difference. I checked voltage at the sensor and it was around 1 volt. Other posts said it should be 5V, but that's if it has a separate knock sensor module. Mine is part of the ECU. The ECU part # is 16197427 and that seems to be common for a lot of different vehicles. I have ordered a used ECU from a 1995 GMC Sierra with a 5.7 engine.

My question is whether or not the chipset is compatible. I know there's a calibration code but I'm not sure what that means. I sure hate to fry a chipset if I don't have to.

 

you will have to have the prom (ecm) programed for the engine ect. you have. The knock sensor resides in the ecm, that I don't know. Either way try what you have, if not, then replace it. Those things aren't as exspensive as the ecm, but arn't cheap. I believe you also are dealing with obd1, that I am not familar with.

 

I'm not sure on this old of a vehicle if the dealer would be willing to re-program it. I looked for a programmer that I could use to do it myself, but all of them were for 1996 or newer. The engine runs fine, but in California, a check engine light is an automatic fail on smog, so I need to figure out what's up. I can't see where trying the replacement, even if it's programmed wrong, could damage anything, but I don't want to make matters worse. Guess I'll give it a try when it shows up.