1990 Chevy Silverado PROM chip in C1500 5.7L 5600 gross wt.

SCPGEOLEVSKI7238

MEMBER
1990 CHEVROLET SILVERADO
6 CYL
2WD
AUTOMATIC
119,200 MILES

Supposing 1 of 3 previous owners changed the ECM but got the wrong chip (say out of a junkyard 7.4L) now causing excess fuel injection, failing low idle emissions test. Dealer can't tell me if chip 16060837 is correct for this truck. VIN -K3LE248471, ECM#7-7747 DC code 0810MT. Chip is also JT8(G)/J6/P, LFIVZ302, AD41. Would hate to waste $95 on a new chip if it's the wrong one. There's not much else left to replace, test, or adjust.

1 Reply

HMAC300

MECHANIC
48,601 POSTS

This will be very hard to find due to chips were made in engineering and that data was never released. I had tobuy a chip for my old 94 but it was a2.8L. But it wasn't $95. When the dealer has parts this old they can't return them to GM and they usually will take what they can get judt to get rid of them. I think what i'd do is find atruck in junkyard and see if it has the same chip or not. At least number wise. You could try it, as it would be probably be cheaper as wellas better than what you have now. In my case I didn't need the chip anyhow as it was a trans problem but had to change that as it read the chip was bad. Hopefully when you did emission test, you changed oil an dfilter, then drove it abou t15 miles on eway then got it tested. That is when they do the best.