Here is the problem... the speedometer will be perfectly fine, then it starts fluctuating...I was traveling at 90mph...look down and the speedometer suddenly it is reading 30, then it starts bouncing around, then it goes back to normal...I stopped and the speedo was fine, then it started bouncing up to around 20mph, any ideas..?

This is a 2001 itr, and what I have installed in the electrical path is an A'PEXi PowerFC, Kenji adapter harness, and a J&S Safeguard. The car has been running around with these electronics for the last 4 weeks, without problems...I did an autocross last weekend, and was at the EXPO this weekend with 7 25 minute road sessions...I'll be swapping in the stock computer a little later...but since I have TODA cams I'm not sure about the driveability.

Thanks for any help,
Austin

 

same deal is happening to a guy here in pittsburgh... he'll be parked, and the speedo will be bouncing upwards of 40 mph. I'm probably going to take a look at his VSS, and the grounds in that circuit. otherwise, troubleshooting will be kinda annoying.

i'll try and advise if anything develops.

D

 

Notice when it does it that your Odometer is climbing as well...might want to mention to the dealer the problem, and act real pissed that your car is appreciating miles without actually moving, get them to extend your warranty maybe

 

what are they going to say about those mods though?

 

Well here is the latest update...the odometer still moves at the same pace as when the speedo is at the correct speed, traveling at 90 mph and looking down and seeing that the speedo is reading 30, no 60, no 0, no 90..ahhhhh, this morning I was stopped at the stop sign talking to Chris on the phone when it jumped to 130 mph while tack was at 1100rpm, stopped!!
Here is what I did today:
swapped the Power FC and Kenji harness out, and the stock ECU still gives me the fluctuating readings(the ECU didn't like the TODA cams and 310's). The PowerFC is reading the same speed as the speedometer, it's just in kph instead of mph.

Checked the connections to the VSS, everything looked fine, took it to a local mechanic friend, and he couldn't figure it out, looks like my VSS went bad...anything else I can check before I call the dealership?

 

Try looking for water in VSS connector, if not try looking for faulty ground at thermostat housing. Last but not least, some cars have wiring that rubs through at the Intake manifold support bracket.(underneath) These may or may not help.

 

It's all fixed The problem was the second O2 sensor had been intermittentlyshorting out, which was causing the fluctuating in the speedometer. That had me spooked, the dealer wouldn't have liked looking at that problem.
Austin

 

They might not have even looked at it... Bolt ons are one thing, but you've clearly exceeded the warranty coverage. And it would take quite a bit of work to get everything back to stock! Glad to hear you worked it out though.