Noticed that my TPS accel keeps going on and off on idle, and makes the idle sound very lumpy. I tried my accel time is set at 0.2 and I tried my TPS thresholds at 10%,15%, and 20% all still the same. I have my accel set at 100% TPS no map. I hope this help. I'll try to get a megalogviewer picture

 

Noise on the TPS line? If the graph in MegaLogViewer looks like a sawtooth then it's noise.

 

my tps in megalog viewer has usually been flat. will post it up tonight hopefully.

 

Here it is ...

 

Everytime there was a spike in PW, there was a change in TPSacc. Looks like noise on the TPS line.

 

How can that be cleaned up? Also how would TPSacc move but my TP(Throttle position i assume it is) isn't moving?

 

I'm guessing there's an intermittent connection in the ground pin on the TPS plug. Either on the harness or TPS itself.

Not entirely sure why the TPS value isn't changing unless it's too fast to show up in the log.

How do you have the ECU grounded now?

 

The ECU ground T's off in 2 positions. One side is bolted on the engine, and the other side is grounded at the battery. This was the only way the CAS would get a clean signal. And I can't remember right now about the TPS .. but i'm pretty sure I had it grounded at the ECU. I'll double check today.

 

Just checked, its grounded at the same point where the ecu grounds on the engine. Would putting a capacitor inbetween the ground and the signal wire clean out the signal to the ecu maybe?

 

Alright so fixed the problem with a couple of capacitors. I placed one between the signal wire and the megasquirt ground at the actual megasquirt. That took off about 1/2 the noise, so then i decided to put one right at the tps inbetween the signal and the ground coming off of it, and that took the rest out. I even brought down my tpsdot to 15 %. No more noise now Was able to tune the car pretty good today too with the tps accel not going off all the time

 

Sweet.

 

Ya i thought i'd post it on here for further reference to other people. If anybody wants to post it up in the msextra.com forum please do so. I've noticed a few people are having the same issue and people have said to ground directly to the MS and twisting the ground with the signal but still hasn't worked for some people. I would of posted myself but they don't allow hotmail emails for some reason :@