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Q: What would cause 1986 454 to backfire through the exhaust while idling?
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Why is your 92 F150 5.0 backfiring through carburetor?

A backfire is caused by many different things. Using the wrong grade fuel will cause a backfire, as the engine's compression ratio is usually too high and will detonate the Air/Fuel mixture, causing a backfire. It can also be caused by advanced or retarded timing. Advanced timing will cause a backfire through the intake, as the spark occurs too early and ignites the Air/Fuel mixture before the intake valve is closed. Retarded timing causes a backfire through the exhaust as the spark occurs after the exhaust valve has opened. Your problem seems to be advanced timing. A backfire is caused by many different things. Using the wrong grade fuel will cause a backfire, as the engine's compression ratio is usually too high and will detonate the Air/Fuel mixture, causing a backfire. It can also be caused by advanced or retarded timing. Advanced timing will cause a backfire through the intake, as the spark occurs too early and ignites the Air/Fuel mixture before the intake valve is closed. Retarded timing causes a backfire through the exhaust as the spark occurs after the exhaust valve has opened. Your problem seems to be advanced timing.


What causes a 1973 Pontiac 350 engine to backfire through the exhaust?

A large backfire is most likely caused by a bad spark plug or plug wire. Unburned air and fuel pumped into the exhaust will often be ignited by the other cylinders still burning exhaust gases. Also check your ignition timing, if it is late and you have a rich mixture you can get a backfire. An exhaust leak will let air enter the exhaust under deceleration and cause a "popping" sound.


How do you cure backfire in an mg midget?

you must have air leaking into the exhaust system that will cause backfire when you decelerate raw gas goes into the system


What would cause a 94 Chevy Camaro 3 4 v6 to sound like a diesel when idling and through some of the acceleration?

muffler or exhaust could be damaged....if it has aftermarket exhaust it will sound different since it is not a V8.


What would cause a 1973 Chevy Nova to all of the sudden start to backfire through the exhaust when you let off the gas?

its running too rich down tune youre carb


What would cause a 1979 VW Beetle to backfire?

There are two things that can cause it. The most likely one is timing too retarded. The other is an exhaust leak. Since your car is fuel injected, you probably have the Exhaust Gas Recirculation system hooked up, and this is where most of the backfire-causing exhaust leaks come from. So it's probably timing.


Can a plugged catalytic converter cause engine to backfire through intake and exhaust pipes are red hot in minutes?

Yes, and it will cause loss of power. Better replace the defective parts immediately before you burn your valves and ruin the engine.


How can you tell a Harley has an exhaust leak?

The engine may backfire excessively. You may also smell a strong exhaust odor in the riding position. In worst cases, it can cause the engine to run lean.


Why does a car backfire?

A car backfires because unburned fuel is getting to the muffler. The heat of the exhause system causes the fuel to combust, thus a backfire. I have just been told that the rubber on my exhaust has split - could this be why the car would backfire? I have heard something about air getting into the exhaust could cause a backfire? back fire can be caused by different faults. first is to much fuel because of worn carburetter, or wrong adjusments on carburetter. choke sticking will cause backfire. timing be out of adjustment will cause backfire exhaust leak can cause backfire. bad spark plugs, or plug leads , distributer cap worn of cracked will cause backfire as for fuel in muffler, if it combusted in muffler , the muffler would split open it is not that. and i dont know of any rubber on an exhaust that would take the heat aexhaust manifold gaskets could be problem but if they were rubber they would melt \ is it good or bad to have backfire It can also be done with intentional modification, such as done in ''Keeping Up Appearances'' British sitcom. A fuel line and an oxidizer line are added to the muffler with a manual rubber bulb pump added to the line as the ''backfire button.'' At a point before entering the muffler, the lines have a pair of backflow valves to prevent the flame from racing into the mixture tanks. Squeezing the bulbs dispense a mixture of pure alcohol and an oxidizer into the muffler to create a reaction. For Onslow's car in the TV programme, copier toner was squirted in the tailpipe for a heavy soot effect on the backfire command. Having a car backfire can shake off any parts that aren't bolted completely, and can cause the engine to stall because the pressure of the backfire can temporarily disrupt the exhaust release from the engine. Besides, it would spook horses, cows, or anyone not used to loud noises. So having the car backfire down a Harlem road won't have the same effect, as a car backfiring down a rural city road.


What will make your 99 Ford Ranger 4.0 l backfire?

Timing will do that, if it is retarded too much fuel will detonate after the combustion cycle. Also plug wires not connected in the proper order will cause a backfire. So will a leaking fuel injector.


What causes a gas fumes on a Nissan maxima while it's idling and you're inside the car?

A bad exhaust will cause gas fumes to get inside the Nissan Maxima while it is idling. Gas fumes, if contained in an enclosed space, is dangerous.


What causes a motor to backfire out of the intake manifold?

A leaking spark plug wire can cause a backfire out of the intake, but the most common cause is a burned intake valve. A burnt intake valve will allow leakage during the compression stroke back through the intake causing a popping backfire out of the intake manifold.