My truck had been running ruff for a year even after a tune up so I cut the converter off hoping that would work but it didn't...the fuel pump is working so what do you think...whatever made it stop was making it run terrible
My car has 254000 miles.
My car has an automatic transmission.
Hello. Rough running can be caused by a number of things. To determine where the issue is I would usually start by scanning the computer for codes. This would help me determine if the issue is at a particular cylinder. If there are no codes then I would do a cylinder balance test to see which cylinders are acting up. Most of the time this engine has problems with the fuel injection unit. This is located inside of the intake manifold. Then unit becomes clogged and restricted and causes multiple misfires. In some cases the unit can be professionally cleaned, but in other cases it needs to be replaced. I will usually do a compression test also on this engine to make sure that it is good internally. If you want to have this problem figured out, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the engine is running rough] https://www.yourmechanic.com/services/car-idle-is-rough-inspection
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