Intake backfire in hot run good at cold - 1997 Dodge Ram 2500 Club Cab

make, model, year? backfires are spontaneous burning (exploding) of unburnt fuel outside of the combustion chamber. suspect bad spark plug/s, ignition coils, ignition timing, computer, leaking fuel injector, etc. scan for trouble codes, then post back. because the problem is intermittent, problem manifests only when hot (engine at operating temperature) do tests for both cold & hot conditions. test resistances (ohm) of suspected sensors: cam & crankshaft position sensors, ignition coils (if possible),(search the web for the recommended procedures). also test voltages at the computer (search the web for the pin outs of the computer of your car). also check associated relays (like for the fuel pump, etc.) a bad relay may have its coil open when heated, then becomes good again when cold. i suspect the car may have a good fuel delivery but the sparks are not coming in on demand, thus backfiring.

have you check for your back pressuire ,check the catalyst converter might be bad

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PCV valve blocked maybe causing a pressure build up

A backfire is caused when your intake valve/s aren't closing completely before ignition in the cylinder. This ignites any fuel/air mixture left in the intake manifold. Fine tune your timing.

Backfiring is caused by unburned fuel igniting in the exhaust system, which could be the header, catalytic converter, muffler or exhaust pipe. Red hot is caused by the burning fuel. You either have a timing issue or you are not getting enough air flow into the fuel injection system, which can happen for several reasons. I would try to find a good local mechanic and pick their brain.

Backfiring is a great symptom because you know what the problem is right away. It seems to be a timing issue. Crankshaft positioning sensor, distributor, electronic ignition, etc. Diagnose your problem concentrating on anything to do with timing. Vehicle just don't just don't jump timing unless something goes wrong of someone does work to it recently. If it backfires from the the exhaust you timing is advance and if it backfires from the intake it's retarded. It's is your firing timing.

YOU HAVE INTAKE MANIFOLD LEAK ALSO COULD HAVE BAD OR STICKING INTAKE VALVES. CODE PO 226 IDM SIGNAL NOT RECEIVED AND CODE PO 542 FUEL PUMP SECONDARY CIRCUIT.

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Check for vacuum leaks with a can of carb cleaner-engine running-spray all around intake and vacuum hoses -if you here the engine bog down or race up there is the leak-too spray around EGR valve.

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dies and is hard to start unless you let it cool off.....fuel pump. Hope this helps tim

If it seems to run better when it's first started (cold) and gets worse as it warms up. You can try disconnecting the coolant temp sensor and jumper the terminals in the connector (wire side) with a paper clip. The coolant temp sensor is either in the intake manifold or the thermostat housing and has a 2 wire connector. Jumping the connector will make the computer think that the engine is hot (warmed up) and will not richen the system. If doing this helps then replace the coolant temp sensor. Hope this is helpful.