1979 GMC Carb issues
You haven't provided a lot to go on here but I'll take a stab in the dark. If you are somewhere that is unusually cold, maybe you just need to let it warm up. Could be the choke is not working, could be the choke is closing but wont open because the heat riser passage in the intake manifold is plugged up with carbon, could be the fuel pump is weak or the filter is plugged and the carb is starving for fuel even though the tank is full.
To check the choke operation, take off the air cleaner lid before you try to start it and operate the throttle by hand while watching the choke plate. It should snap shut. If it does rack the throttle two more times, start it up and watch the choke plate. it should open just a little (maybe 3/8') on a cold day let it run on fast idle for a few minutes, as it starts to warm up the choke should open more. And be fully open after a little while. Given it's age it would not surprise me at all if the carburetor is not working right. If you are going to take it to a shop, look for a mechanic in his late 40's. I know that sounds weird but most of the young guys out there have never even seen a quadrajet let alone rebuilt one.
Jan 28, 2014 |
GMC Sierra 1500 Cars & Trucks