HELP...Troubles setting up my TPS sensor

[Tommy]

I'm setting up my TPS and IAC in my 87 GN and a problem that I am running into is that the TPS once set at idle voltage of 0.40 volts cannot achieve the 4.5 volts at WOT and only getting 3.78 volts. I've checked and confirmed that I'm getting WOT at the throttle body blade and it seems like the TPS sensor needs another 1/8" of travel or so to get it to the 4.5 volts.

The TPS has a smooth voltage increase but again I'm not getting the 4.5 volts with the throttle lever travel any ideas...is the TPS faulty?

Regards,

Tommy

 

[chops]

1st off make sure your floor mat is not in the way!!!!!! Its happend many times also try turning the sensor all the way down then back up again and try resteting again any problems shoot me a pm I've done it to many times my self bets of luck tommy!!!

 

[TurboBob]

loosen both TPS screws and slide it towards the front of the car as far as it will go and snug it back down. Then set the idle. Then see how much the WOT reading is.

B

 

[GNRick]

This might help....Basics Position Sensor Adjustment

 

[GNDriven]

I have taken a small round file and elongated the mounting holes. Like mentioned above, the further you move it forward the higher the resulting voltage be at full throttle

 

[bsdlinux]

I have taken a small round file and elongated the mounting holes. Like mentioned above, the further you move it forward the higher the resulting voltage be at full throttle

+1 This works well when standard adjustment won't work. I've owned 3 TRs and only 1 car needed this to get it right.

 

[coach]

I just did this a month ago. I tightened it enough that I could test it and then tap it a little. You actually end up tapping it up or down, not forward or backward. That allows you to keep the idle setting and increase the throw for the wide open setting. That is why the slots are molded on a diameter, and not just elongated holes. Mine was tricky, but ended up at .38 idle and it goes to 4.68 at WOT.
Beware, the floormat is an issue most do not think of. It can really mess you up.

Thanks
Coach

 

[Tommy]

I just did this a month ago. I tightened it enough that I could test it and then tap it a little. You actually end up tapping it up or down, not forward or backward. That allows you to keep the idle setting and increase the throw for the wide open setting. That is why the slots are molded on a diameter, and not just elongated holes. Mine was tricky, but ended up at .38 idle and it goes to 4.68 at WOT.
Beware, the floormat is an issue most do not think of. It can really mess you up.

Thanks

Update:

after reading everyone's advice the best that my TPS can do are: 0.41 V at idle and 4.4 V at WOT and this is setting the IAC with about 1 1/2 threads out as I don't have a scanmaster (yet).

I started the car and it revs up to ~2,000 rpms and then comes down to ~900 rpms at idle. Is this about where the idle should be on these cars? The idle seems to be quite stable.

Thanks
Tommy

 

[A2000RICH]

also check one thing------the tps is just a heavy duty weather resistant potentiometer-------as such when it is moved from one extreme end to the other it should output 0 to 5v--------if the blade on the tps is moved independently of the throttle shaft you should be able to make it go to 5v--------i have seen at least one brand of aftermarket tps that will not go all the way to 5 volts due to poor internal design--------if you start out with one of these you are not likely to ever get it right

 

[TurboBob]

its likely that the startup and idle are correct. The factory tachs have not aged gracefully, so you can't really trust it. Once you get a scantool you can fine tune the idle stuff, but if the driveability is good, then you will be fine (the TPS setting is not that critical).

A2000RICH: good advice as always.

Bob

 

[pacecarta]

whats the IAC reading ?
if your tach is correct (what are you using to read rpm?) my guess with 2000 flare up and 900 idle is the iac is not set correctly and is at 0 and then some ..the throttle blade is open too far and cant come to rest where it should making idle at ecm programmed setting impossible


close the tb blade by turning the screw on driverside counterclockwise get the iac correct (10-20 counts) with the tps under .46 then try resetting the tps , doing this youll probably find that the tps WOT value will be able to be increased without any grinding