Hello.
i have a bone stock 1986 Blazer K5 with a 305 engine with 46k miles. I have read numerous service manuals and to my understanding there were various version of ignition. I have the 4 barrel m4med carb. My question does all these k5 have the ECM? I don't think mine does. I have been having very bad fuel mileage and seems to be flooding out with low power. Very strong odor at exhaust. Have checked all vacuum lines and replaced some as well. New distributor, spark plugs, plug wires, even engaged the carb pump solenoid. Any suggestion would greatly be appreciated.

 

Does it have any electrical connectors on the carburetor? Does it have a check engine light? Does it have a diagnostic connector under the dash? Does it have an O2 sensor? Those would all be indicators that it is computer-controlled.

 

Thanks Tom. Just did some reading and it seems this year had 3 different types if ignition systems. A HEI, HEI/ESC, and a HEI/EST. Mine has the HEI/ESC and this type has a electronic spark control module. My problem could be in the egr or gas system. I guess lots of digging I'm gonna have.

Thanks