Q: Rough to no acceleration and misfire

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My truck starts and idols just fine besides it sounds like a diesel from a bad knock or tick. Low speeds below 15 mph it seems to run OK. When accelerating it feels like it is bogging down with very little to no power. Most of the time when it does this the RPMs also rise without actually accelerating any faster. If you stay on the Excelerator while it is doing this it sounds like a backfire over and over again just not as loud as a Becvar normally would be. It makes no difference whether it's hot or cold Outside it does the same thing. Last week it would not accelerate past 25 mph at all so I change the mass airflow sensor and it seem to help I can drive it now but is still very. Whoever owned it before is did not take care of it at all. We have changed all fluids, MAF sensor, brakes and rotors, flipped the body lift over that was installed upside down, battery and changed one wheel bearing. Also have run many different fuel cleaners and fuel system conditioners. Thank you

My car has 128000 miles.
My car has an automatic transmission.

It is possible that one or more of your spark plugs or ignition coils have failed. The spark plugs and the ignition coils make up the ignition system and this system is responsible for burning the fuel. If the fuel is not being burned properly, the engine will not run well at all.

I would recommend having you ignition system inspected by a qualified professional to determine if the truck is in need of a tune up or if any of the ignition coils have failed. These symptoms are likely associated with a Check Engine Light as well so checking the trouble codes will aid in the diagnosis of this issue.

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