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Q: Car jolts while accelerating and won't accelerate from stop.

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I've been having this problem for a few weeks. My car will jolt on acceleration, and lately when I try to move from a stoplight or after braking, the car doesn't move forward after I release the brake and I have to step on the accelerator really hard to get the car to move. I thought it might be a problem with the fuel injectors, because when the problem first came about I used some fuel injector cleaner and the problem improved and almost went away. Adding some fuel injector cleaner helps slightly now, but not always. My mechanic said it just smelled like old gas, that I should use plus gas for a week or two, and he tuned up my car. My car felt much better for about two days, but now it's back to the hesitation again.

My car has 90000 miles.
My car has an automatic transmission.

A: Hello. From what you are explaining it soun...

Hello. From what you are explaining it sounds like you either have a failing fuel pump or a bad catalytic converter. Both of these issues will cause these symptoms.

I usually start by scanning the computer for codes first to see if there is any indication of a bad sensor. If those are fine then I check the fuel pressure. If the pressure is below specs then the pump needs to be replaced. If it is fine then the converter back pressure needs to be checked to see if it is failing as it will clog the exhaust and keep the engine from building power.

If you plan on having this repaired, consider receiving assistance from a certified mechanic who can come to your home or office to diagnose this lack of power and get your car running normally again.

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