I had engine hesitating and bucking at low load for quite sometime now-between 1500 and 2500 rpm-any speed or temperature, any brand of gas, any gear. Very annoying and almost embarrassing to drive car like that.
No codes were stored. I did a research and read all about knock sensor harness replacement.Ordered the harness, gaskets and the sensor-some parts are still in transit.

Yesterday I was checking oil and decided to clean engine grounding points. Not sure how many there are in total, but 4 are quite obvious -VERY thin wire coming out of the injector/ignition harness right in front of the engine(be careful with it), one below coolant overflow tank, and two points on the left side of the engine-pretty easy to see-really thick harness goes there. One of the points is below coolant hose.

Unbolted them and cleaned the clamps with sandpaper. Took me about 10 minutes and 95% of hesitation was gone! Idle became super smooth. Car has grounding kit BTW.

I will replace knock sensor harness anyway, but for those of you with hesitation issues cleaning ground points might be a good place to start.

Can anyone contribute if there other engine grounding points which are fairly easy to get to?

 

I recently had the exact same issue, but it was the knock sensor and harness - not grounding related.

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