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Discussion Starter · #121 · (Edited)
Ok, so I have to isolate for a while because of our current Covid restrictions so I haven't gotten new o-rings/caps/clamps yet for my leaks that I've found... but I did swap in the new TPS and have done the basic tests. I had meant to do this a long time ago, but tested my original one without finding a problem at the time (while waiting for the new one to arrive in the mail) so never actually tried swapping in the new one until now.
Anyway, finally swapped in the new TPS, it seems to pass the tests I've done so far though I'm still getting the P0120 TPS sensor code. I'm using the scantool from BlackStealth, configured for my Chrome ECU). Videos in link below.
I'll likely put up a separate thread just title TPS testing so anyone else can find it easily in a search. I've seen a lot of posts/threads asking about the TPS and I always find it helpful to see pictures/videos so figured maybe this can help someone else.

Questions I have after the TPS swap/tests (I won't be able to drive/log a drive until later this weekend):
1: is there any 'break-in' time where the ECU has to learn the new TPS? (long shot, but there are plenty of things I don't understand in the ECU so the hopeful side of me says maybe it'll only throw the code until after driving a while with the new one?...)

2: any idea about the reason for throttle 'bouncing' around 2600rpm? (this didn't exactly happen with the old TPS, but maybe this is the same hesitation as before just at a different point...). I believe this may still be my main hesitation problem, though the TPS change/adjustment seems to have had an effect on when it happens.
edit**: I have a log of this but may not be worth going over until I can take an actual drive for a better log

3: on my scantool I noticed my throttle only goes from 2.7 to 85.4%... I only noticed this after all of my other tests were done. I'm reasonably sure I have to reset the TPS again:S. From my searches I think it's normal to start at ~13% in order to get all the way to 100%. (my set point may have been a little off because getting that feeler gauge in proper position was a pain in the ass... but I will redo the set procedure to fix this.) I have a feeling that after resetting this, my hesitation(/throttle bouncing while in neutral) will just be higher in the revs so maybe no different than with my old TPS. Any thoughts?

link to videos:
 

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Discussion Starter · #122 ·
Another update after readjusting the TPS:
I wanted to try adjusting the TPS using the scantool throttle% readout instead of messing with a feeler gauge... maybe it's not the right way to do it... but I'm actually hopeful that it may have worked.
(I have no doubt the feeler gauge method works, but at least in my case I wasn't 100% sure I had it properly in place (ie not on a bit of an angle throwing off the spacing completely).

I first removed/replaced the TPS to ensure I had it properly set/lined up. I then loosened the bolts on the TPS enough to be able to twist the sensor as per the normal method.
Now, instead of messing with a feeler gauge I had the key set to the on position with the scantool connected so I could see the throttle% readout. I have read that when at idle/foot off the gas the throttle % should actually be around 13% (not 0), so I twisted the TPS slowly clockwise until the readout was 13% and tightened it down there. I should also add that I redid this with the car running and warmed up. (This may require more in depth follow up as to why 13%...but it was a starting point anyway).
Once the engine was at operating temp I tried revving again... No more hangup at 2600RPM, and smooth increase!
On top of that, I cleared the engine code, rescanned and this time no code was thrown!

I don't know if this is just false hope, but I am really looking forward to taking a test drive/logging with the new TPS set up this way.
 

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12-13% TPS reading from the ECU with 0 pedal input is correct. Anything below ~10% will throw a code as you experienced.
 
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