Q: To much fuel and not enough air flow.

asked by on August 29, 2016

I replaced the spark plugs, spark plug wires, distributor cap and rotor. Somehow the truck is still getting to much fuel and back fires when you get on the throttle. The TPS sensor is good. But the only problem I have is that the check engine light is not on. Could it possibly be the MAP sensor?
My car has an automatic transmission.

Hello.

The issues you are experiencing can be caused by many things. A rich condition can be caused by a faulty fuel pump, fuel pressure regulator, leaky injectors, a faulty MAP sensor, and many more.

If any of the fuel system components are faulty and throw off the fuel pressure it may cause the vehicle to run rich. Just the same, if any of the vital ignition or engine management components fail, they can throw off the computer and also cause a rich condition. If there is no Check Engine Light then it may be possible that the issue is not related to a sensor, perhaps a gasket is torn or an injector is leaking.

If you are unsure, I would recommend having the vehicle looked at by a certified professional, like one from YourMechanic, to diagnose the backfire firsthand as the possibilities could be many.

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