Q: Car jerking often, check engine light flashed and stayed on.

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Saab started violently jerking once in a while. Once it totally stopped and wouldn't restart so I had it towed. It wouldn't repeat the problem for the mechanic so they thought it was the fuel pump and replaced it. They also check vacuum seals and compression. Problem is happening more often and the other day I drove it about 10 miles babying it all the way home. Next day drive it a couple times around the block and it did it again. Turned it off and when I tried to restart it wouldn't. Then, five minutes later it started. Now, it's just sitting in my garage as I'm afraid it nay leave me stranded. The throttle body was recently replaced because it stuck wide open. The repairs are getting to be very costly. 🙁

My car has 110 miles.

What you are describing sounds like a dirty or faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

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