A few times a day when I drive my '05 GT (which is an automatic), I'll notice that my RPM's slightly surge.

1) This never happens when I'm just idling at a light or anything. Only when the car is in gear and is already moving.

2) For one example that happened today, I was going about 40 miles per hour, 1800 RPM's, coasting to a stop. My foot was off both the brake and the gas. Just a few seconds before I was going to hit my brakes, I noticed and felt the RPM's rise a little and looked at my gauges. The RPM's went from 1800 to 2000 for just a second and went back down to 1800.

3) Another example: As I was driving down a road at about 50 miles per hour, my foot was on the gas pedal, but I was just crusing. I didn't push the pedal down at all and the RPM's surged.

4) When the RPM's surge like this, the car doesn't accelerate with the RPM jumps. I can just feel it through the pedal and see it on my gauge. I can't really explain it. I'll be just driving along at a crusing speed, I'll feel the RPM's raise, look at the gauges and watch it, and then it stops and goes back to normal.

5) When I crank the car in the morning, the idle starts at about 1000 and goes all the way up to about 2200 for maybe 3-4 seconds and then goes back down to 1000.

6) I uploaded a new 93 octane custom tune from Justin at VMP Tuning about a month ago and the car never did this until then.


With all that being said and with #6 taken into consideration, I'm assuming that it is in the tune. If so, how the hell do I fix this? I know it isn't supposed to do this. It's not something major and I don't notice any issues with the way the car drives, it's just puzzling to me.


Also, the shift points are waaaaayyyyy too soft for my tastes. What can I do to make them more firm? I know I can change the shift points, but can someone explain to me the proper way to do it so I don't **** something up?

Thanks for your help guys. Like always, I appreciate it.

 

Their could be some part of the file that Justin sent you that got messed up in the transfer. I would email him about that and tell him to make the shifts firmer and he will take care of you.

 

The idling issue you can adjust on the SCT if its the XCal3/SF3. Mine idles at 720 and it's great. The warm-up RPMs sounds like a bad tune. It shouldn't go up to 2200, maybe 1500 at the most.