GregM

I had power tuning installed along with my gears program installed on my 98 z. I wanted to get rid of power tuning and accidentally set all my tuning back to stock, so reprogrammed the gears back in. Now whenever I rev the engine sitting still, my speedo revs too.....what's causing that???

Sparky

Strange! May not be a programmer problem though. Try resetting everything back to stock and verify operation. Still there? Not a programmer problem. Problem gone - call HPP!

Mark

Beth

My speedo did the same thing. I took the HPP programming out a year ago. Never rev'd the engine until after header install, about 2 months ago. While I was listening to it, the speedo jumped around 3500 RPM. I have not checked it to see if it still does it, but I bet it does. It is accurate while I am driving, so I did not worry about it. Now you're making me wonder......

MIGHTYMOUSE

iTrader: (59)

i would undo it totally, make sure the car is ok, then reset the cars computer.. make sure its ok again, then install just the gear tuning.

Ira

This is a bit of trivia, but on the 97 and 98 instrument panels the speedo and tach signals are on pins 14 and 15 ot the bottom row of pins and they pretty much both use the same signal. It's slightly reasonable that under the wrong conditions that there might be crosstalk and the tach might be able to drive the speedo. Try something for me if you would. With the car parked on a level surface and a couple of bodies, see if the problem happens and then very slowly push the car 10 feet and see if the problem comes and goes evey foot or two of movement.

Ira