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Q: What causes spark knock in motor at idle and backfire?
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What causes 1988 Dodge Dakota tuck backfire?

Backfire is normally caused by engine out of time, or spark plug wires installed incorrectly.


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.


Why is your engine knocking on BMW745?

knocking as in spark knock? or engine knock? spark knock is adjusted through a knock sensor via ignition timing. eng. knock is due to brg. knock as in low oil pressure or sluge in engine or just a tired motor


What is a knock sensor on a 3800 series 2 supercharged motor?

The knock sensor detects spark knock (aka ping), sends that signal to the engine control module (ECM), the ECM retards the timing until the spark knock stops.


Why does your motor backfire out of only one exhaust?

Possibly you have the spark plug wires connected incorrectly on that side of the engine. Timing can also be off.


What causes your car to backfire when you try to start it and will not start?

The timing of the engine is off or the spark plug wires have been hooked up incorrectly.


Could a anti knock sensor that is unplugged or defective cause problems with the 305 motor starting?

No, a faulty knock sensor will cause a code 43 normally. check for spark, diconnect a wire from a plug, install a plug in the wire, lay it on something metal, have an assistant crank the motor and watch for spark...


Why does a rototiller backfire when starting?

A rototiller may backfire when it is starting because the valves need to be adjusted. Another reason that it might backfire is because you have to replace the spark plug.


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 Backfire when starting engine 1999 ford ranger 3.0L?

There are many causes to this problem, in a 1999 Ford Ranger 3.0L. It is usually caused by a spark plug firing when its not suppose to, or late/delayed timing.


What could be making a noise like a spark knock in a 2001 Jeep Laredo have replace serpentine belt and tension pulleys - that was not it?

If it is making a noise like a spark knock, maybe it is a spark knock.


Will the knock sensor make the smoke?

No. The knock sensor's purpose is to detect spark knock (pinging) and send a signal to the ECM to temporally retard the timing until the spark knock stops.