My car jerks forward occasionally at high speeds, what could be the problem (more details inside)?

Question

If I drive on the hiway for more than 20mins, my car will every once-in-a-while jerk forward for a brief second before carrying on like normal.

When I come to my first stop after leaving the hi-way (like a traffic light), when I pull away it jerks forward quite badly. After that first stop, it'll drive like normal again. What could be the problem?

Answer 1

You need to have a tune up. Check on the following:

-  Spark plugs; high tension wires, distributor cap, if any; fuel injectors/carburetor; fuel filter; timing, accelerator cable among others.

If it still persists, call a qualified mechanic to check on other related systems.  Jerking while in motion sometimes is caused by a deformed tire/s, just an add'l. info. Good luck

Answer 2

could be a misfire

Answer 3

First if you have never changed the fuel filter do so!

Also could be water in fuel tank.

If this does not work have you Oxygen Sensor check by having a diagnostic test run for O2 Sensor code.

When you say jerks forward do you mean you are pulled back into the seat or forward in the seat?

If you are jerked forward in the seat then I suspect the above conditions first, However if you are jerk back into your seat when the vehicle jerks forward perhaps your transmission is switching into a higher gear prematurely.

There is one other thing that come to mind and that is the fuel throttle position sensor. I may not have the name correct on this one, but it is this or something close to this in name and function.

Good luck, Hope this helps track down the problem.