E36 TPS noise - already shielded vref and signal wires

[saturnv7890]

Like the title says I'm experiencing some bad noise with my E36 tps. Here's the log, it appears I only get the noise when the car is on:


(I know the log looks bad... turns out I had a spark plug unplugged)


I've already shielded the wires going to pins 52 and 53 on motronic for vref and signal.

Where is a good solid ground I can use? Would a shielded wire running to a good ground help tame this signal?

It's really annoying using MapDot, as this really sucks for some reason. When I get on the trottle the car like stops for a split second before accelerating nicely.


Any other things I should try? I know Nando said in a thread that wires not hooked up properly will cause noise and calibration issues. I don't have any calibration issues I don't think.


Would love any helpful input on this issue, I love how smooth the car is with tps ae, but the noise really messes up my AFR's and the car is really inconsistent at constant speeds.

[e^2]

Are you grounding the shield on both ends or just at the ECM?

[saturnv7890]

Just at the ecm

[nando]

did you swap pins 1&2 before hooking it up to the stock E30 TPS connector?

[saturnv7890]

Doesn't appear that they've been swapped, is that worth a shot then?

[nando]

Yes, the backwards sensor makes noise issues worse.

[saturnv7890]

Okay I'll try it out and let you know how it goes!! Thanks for the reponses! I'll be back tonight with results

[saturnv7890]

Oh here's a quick one, which one is pin 1? Brown/blue or brown/black?

[nando]

I think they are labeled, but they're definitely shown in the ETM by wire color and pin #.

[saturnv7890]

Got it, I cut the blue wire and nothing blew up!!



Switched them and it helped with noise a little bit.. now tpsdot is definitely useable, but it's still a little messy. Any more ideas?

[e^2]

Does the noise show up on any other sensor inputs?

[saturnv7890]

Here is a log:

http://s000.tinyupload.com/?file_id=14250621301742515535

It appears that a lot of the signals are noisy, but that could just be the constant variations in the actual info they are reading?

[nando]

Your link doesn't work.

what does your power signal look like? it should be pretty flat at around 13.5-14v.

if you have noise issues elsewhere, they will show up in all your sensors. how is your MS grounded?

[saturnv7890]

http://s000.tinyupload.com/download.php?file_id=14250621301742515535&t=1425062130174251553518003

Try that link. The download link you have to click is hidden in this looking group of text:

To download file click the link below:
6 11 13 PULLS.msl <-- this is the one you click
Filesize: 2.132 MB
File upload date: 2013-06-13 14:33:48
Number of downloads: 1

I'm on my work computer right now so I can't take a look at the log myself :(

The MS was installed by the PO (jordan325ic) so I guess I'm not entirely sure how he grounded it. It was a PNP made by RS4pro3 so it might have used the factory grounds? Where would you recommend the MS be grounded?

[nando]

the factory grounds are fine - but you might want to make sure they are clean, tight, and the wires are in good shape.