Tps help

[jsimmons]

I have a ford 4 wire tps (PN AG1E-9E928-BA), according to what im finding online it has 2 signal wires a vref and a ground. I notice the pin outs for ms3pro only has 1 tps in.. so how should i be wiring a tps sensor like this?

[DaveEFI]

You need to check it out with a DVM set to resistance. I'd guess the fourth wire may be an idle switch

Set it about half way and find the two wires with the highest resistance - probably about 5000 ohms. That is the track.

Set it to fully open and measure between each of those to the other two. The lowest resistance gives the wiper (probably) - and the track wire which goes to V ref. The other track wire goes to sensor ground. The wiper is the pot output.

Check between the wiper and either of track wires. Slowly move the pot over its range and the resistance should change smoothly.

Once you have identified those three, you can determine what the fourth wire does - and ignore it.

[jsimmons]

I probably should have said i already know which pins are qhich on the sensor. I just need to know what to do with the 2 signal wires or which one to use rather

[DaveEFI]

Testing with a DVM should show what the difference is.

[jsimmons]

Well I think my new throttle body came with a dead TPS. I tried using a Ohm meter to measure the resistance to figure out which pins were what but as I open the throttle it doesn't show a resistance increase no matter which combo of pins I'm testing. I'm going to call the people I bought the throttle body from in the morning and see what they can do for me. I did take the tps sensor off the tb and it rattles on the inside. I also noticed that it (TB) has 2 sets of screw holes which I'm guessing is to mount 2 different styles of tps sensors. If the people I bought the tps from don't help me ill take the tb to a parts store or a junk yard and try and match up a 3 wire tps

[jb007]

Just a thought, a lot of people don't know this, but the US company Wells, makes replacement TPS using Hall effect technology in some or most of there replacement TPS, which means that they don't wear out like resistive TPS's. The output is very smooth and once more the idle and WOT voltages are very repeatable, no more negative readings in TunerStudio when it goes back to idle!. If I can get a replacement for my GM TPS locally I'm sure that you can in the US. My 2 cents worth!

Jim

Just an update:
I think from what I can find, is that your TPS is a Wells Electronics TPS4212 but it is just an educated guess, see http://www.wellsve.com/parts/index.php? ... NO=TPS4212
Info on their non-contact TPS's: http://www.wellsve.com/advantage_throttle.html
Might pay to check that they have your TPS in non-contact, and also they didn't change P/No's so some re-sellers might have NOS that is the contact (resistive) type.
PS, I have no shares in their company, just happy after wasting money on 4 TPS' that developed problems way to soon!

[jsimmons]

Thanks for the info man. I did wind up calling the vendor i vought the tb from and they are going to send me out a new throttle body.

[jsimmons]

Ok so turns out the tps that comes on the tb is a switch type and is useless. I did manage to somewhat match one at the auto parts store. well at least the bolt holes line up and it turns the correct way. Now my question is I have to rotate it a little to line the bolt holes up because the teeth on it don't match. so it is partway through its travel/swing at closed throttle. it will still allow me to open to WOT but there isn't much movement past that. So I'm guessing it would be showing really close to 5v at full open. Will this be a issue? If it will be I can grind down the theeth in the tps and use some epoxy to make a new set of groves in the tps to match my tb. My main question is will I be ok with it like this or should I make a new grove in the tps to match

[billr]

That will probably be OK as-is.

[slow_hemi6]

Yes I would keep it as is. it is better to have some preload on the TPS and a lot do from factory. As long as you still get to full opening without the tps binding or going full scale prematurely you are all set. Just use the calibrate TPS function in tuner studio.

[jsimmons]

Thanks for the replys guys..