What might cause a 6-cyl 1986 Chevy Astro van to backfire?
It can be eithier plug wires crossed or burned valves. Have it checked out.
Will a stopped up cat converter cause a 1992 Chevy van to flood and backfire?
My first thought is that you have a burnt distributor rotor or cap,remove the cap and look for small thin lines that have a rainbow effect around the edges of the lines.If all looks good here,you might consider looking closer at the cat converter,most times when they are stopped up you will hear a sound i describe as a hiss or vacuum cleaner sound,hope this helps
Your 78 dodge 360v8 keeps back firing when you put it gear you checked you have the right firing order what else should you be checking?
It has been my experience that most backfiring problems are cause by intake vacuum leaks. You might want to check the torque on the intake manifold retaining bolts or it may be a worn intake manifold gasket. You might also want to inspect the vacuum hoses for cracks or loose connections. You might also check the timing. If the timing is off, it can also cause backfire and starting problems.
Why does 1990 MTD ranch king backfire?
If it backfires after you shut it off then it is probably running too rich. Any unburned gas the that is exhausted out and into the muffler will explode with a backfire. With a 1990 model you won't have the anti-backfire solenoid on the bottom of the carb like the newer ones have. If it backfires while it is running it might be out of time. Check the keyway between the crank and flywheel to…