Originally posted by mike street
1988 blazer k-5 130k just tryimg to get this thing to run better
i read some stuff about reseting the trouble code computer buy taking the use out of the ecm and disconnecting the by pass when setting timing
you can reset the computer by talking the bat cable off for a min but that dont fix anything. you need to check codes while the code is in the computer. if you wont to set the timing you need to unplug a light tan wire over next to the brake booster set the timing and plug it back up.

Turn ignition switch to OFF position
Locate Data Link Connector (DLC),
Jumper the A&B terminals(a paper clip or a jumper wire work ok)
Turn Ignition switch to ON position.
Count the flashes on the "CHECK ENGINE" or "SERVICE ENGINE" light.
FLASH, pause, FLASH, FLASH = code 12
NOTE: Some 94 & 95 models do not have the B terminal. In which case a scanner is required.
NOTE: Some 94 & 95 models that DO have the A & B terminals still require a scanner. after you get your codes lrt me know what they are.
All vehicles after 96 are OBDII,and require a scanner to access them.


check the codes and let us know what they are. the DLC link is under thr dash on the drivers side.