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Q: Loss of power like misfire under any load

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The car starts but runs rough on idle sounding like a misfire. It struggles under any load like hills or acceleration. If i use the kick down the problem goes away and the car runs well until you level your speed again.

No engine warning lights have come on at all. I have replaced the lambda sensor, mass air flow sensor two coil packs, 5 spark plugs, 5 fuel injectors (used) and had the vaccume hoses checked and found all good. Could it be the cam sensor? Any help would be appreciated as it is getting costly now.

My car has 173000 miles.
My car has an automatic transmission.

Hello. To start, you mentioned that you had switched out the fuel injectors. Have you checked the fuel pump and filter? Being 16 years old, the vehicle may be struggling due to lack of fuel pressure.

The Check Engine Light does illuminate with every diagnostic troubleshooting code. You may want to have the vehicle scanned anyway. If you are having a camshaft position sensor issue, it may show itself here. Keeping to the simple things first, consider the age of the battery that you have. A weak battery can also cause drivability issues. The recent repairs should also be verified. You need to make sure these repairs are holding. An improperly gapped spark plug can cause a misfire. Try having the previous work double checked first. If you would like to have another mechanic inspect the car’s loss of power for you, a certified technician from YourMechanic can diagnose the problem and follow through with proper repairs.

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