So I've searched and understand that there are basically two solutions to this problem: 1) Add ground wires to the engine or 2) go to an aftermarket ECU. My question is...is the 3k hesitation a result of the stock ECU affecting the ignition system or is it affecting the fuel system?

Thanks,
Steve

 

I would like to know this aswell.

 

The grounding fix is not a fix. It does not work on all FDs.
A stock re-programmed ecu still can have the problem.
The first and always 100% fix was the PFC ecu!

I do not remember ever reading the cause for the problem.

 

Adding grounds, specifically from the negative terminal of the battery to the chassis, DOES help the 3k hesitiation. BUT, you can never eliminate it from a stock ECU, just minimize it.

Supposedly it's how the stock ECU handles the fuel injector transition - when it brings the secondaries online.

The PowerFC TOTALLY eliminates the problem. Even cars with bad 3k hesitiation have it disappear with the PFC. That just points out the problem is the programming of the stock ECU.

Dale

 

Playing devils advocate here...

Here's my problem with saying it's the ECU "only". These cars didn't have the hesitation off the showroom floor, yet they came with the stock ECU. Not all cars develop or have this hesitation with the stock or rechipped ECU's even at higher mileage counts. The cars that do develop it, have developed it at different points of their lifetime (i.e. the old myth of the stock ECU changing it's programming at 20k miles doesn't hold up).

This points to something else in the car which the stock ECU uses, but aftermarket ECU's most likely ignore (as the PFC and other programmable ECU's ignores a lot of the sensors/solenoids that the stock ECU does not). While the PFC can remove the issue, I believe the issue has been falsely advertised that the problem is solely in the stock ECU.