slimjim16

OK ive got a few questions here about setting the TPS as im trying to do it and I am running into problems. its a 87 TII

Heres the steps ive been taking Plz let me know if im doin one of them wrong thx.

-so first off i warm up the car to its normal operating temp.

-then i pop off the intercooler quick

-hook up my digi multimeter to the one wire on the far left of the TPS and then to the next one on right side of it(the middle of the three).

- now ive gone both ways with the adjusting screw and i think last night i got to around .80 volts (and im aiming for 1Volt solid right?). then i got to the point were i unscrew'd it so far the adjusting bolt came right out wont losen any farther, so i thought hmm well maybe im goin the wrong way but i screwd that bitch in pretty far and im only coming up with around .07 - .08V.

as for the setting on the multimeter its set at Batt check, 1.5V i figure its the lowest voltage on there and i tested it with batts and it reads them good, so i think i got that set right.

im just confused and dont know why i cant hit 1Volt on the money without unscrewin the dam thing all the way . im in desperate need of help here as im tryin to figure out why im running so rich , i wanna make sure the TPS is perfect before i try and mess with the timing as it stands right now , she doesnt idle low enough to do it so, PLZ Help if you see anything wrong im doin in these steps let me know it would be greatly apreciated, thx slim.

ilike2eatricers

You want it set for 1k ohms. Here is a write up RETed did. http://fc3spro.com/TECH/HOWTO/TPS/tps.html

HAILERS

No, you want to set it at approx 1volt with a fully hot engine. I think you have a meter reader problem. What are you using for a ground on your meter's negative lead??? And are you leaving the TPS plug connected when you do this. You should leave it connected. You should be backprobing the GREEN/RED wire on the Harness side of the TPS connector.

Even if you set your meter at a higher voltage level, it should still be able to read one volt without any trouble. A lower scale is preferable. Digital meter????

Oops. Read your post all the way thru. Put your negative lead on a known ground like the battery negative post or part of the engine itself.

Remember, look for the green wire with a red stripe. It's the output of the tps. Make sure the connector is fully connected together. Positve lead in the back of the green/red wires receptacle.

Ocelot

When warmed up, it should be 1ohm with no throttle, then it should go smoothly up to around 5ohms depending on the throttle. The screw adjusts the resistance, so I don't know what this guy is talking about with the voltage.

pitchblack7

voltage if you do it at the ecu, ohms if you do it at the tps

HAILERS

And I've no idea what your talking about.

IF you ever get the chance, pick up a factroy service manual (free and online) and look in the Fuel Section under Control Unit. In that area you WILL find that a properly adjusted tps will give a reading of approx 1V at idle with a fully warmed up engine.

Voltage checked at pin 2G on a series four OR it can be checked at the green wire with a red stripe at the fully connected tps plug. Key to ON, please.

ilike2eatricers

So measuring the voltage at the ecu i better than measuring resistance at the TPS wires?

HAILERS

NO. Read my last post. And if you decide to adjust using the so called resistance method, please disregard the bullshit about 1ohm and 5ohms. It's 1Kohm and 5Kohms respectively.

slimjim16

ahhhh ok the ground part makes sense and Yes Hailers is right with the 1 Volt, it does say it in the manual and i have been told by many that it should be at 1 volt with a fully warmed up engine, key on, engine off. Hailers ill give the ground a shot and ill let yall know what happens, thx again slim.

ohhh 1 sec, the part you said about the TPS plug..... unplug it? or just go off the green / red wire?

if i unplug it wont it not have any power therefor not give me a voltage reading?

HAILERS

Leave the connector connected. I don't know what your meter leads look like, but I backprovbe the green/red wire thru the back of the connector. Other times I've used a needle to ***** the green/red wire and put the meter lead to the needle. The green/red wire is located on the harness side of the connection, NOT the tps side of the connector.

Actually, believe it or not, I have no real argument against doing it the ohms/resistance method. If you do it that way, with the connector apart and just looking at the pot in the tps, you can detect a open spot in a tps. It is a good method for checking for a faulty tps. On the other hand I can do the same thing by watching the voltage reading on a meter and I can do it much faster. I have faith in my tps.

Yes, leave it connected is the answer to your above question. Key to ON when you do it, please.

ilike2eatricers

I already have my TPS set to 1k ohms and about the 1k-5k ohm you are correct and it is only a general range. I also have my SAFC2 to check the voltage readings as well so that's a double check. I think in the FSM is says from 1k-6k ohms, but dont quote me on that. Anyways, a major point that should be made I think about doing a slow sweep of the TPS is to check for any dead spots in the TPS operation.

Ocelot

I'm looking at it right now and its telling me Kohms, so I forgot the K, sue me, its not like it wouldn't be obvious once he started to test it, but the FSM says check the ohms.

slimjim16

OK so heres the deal, i just went out there and tried the Ohms test to see if it reads the throttle properly and here was my results

multimeter set at 200k Ohms
idle: .7
full throttle 5.6

then voltage wise the highest i can get without unscrewing the screw all the way is around .25volts at the tps side and ecu side.

so im not sure whats up it seems to read throttle response allright, im gonna go get another screw that is a lil longer and see if i can get it set a 1volt bang on.

but idno think that my TPS could be fucked with these results?

HAILERS

Some *Thing* does not sound right here.

If you turn the screw anti-clocikwise, the voltage should drop. Turn the screw clockwise and the voltage should increase. Your results sound the opposite.

You can get by without warming the engine IF you reach over to the aft outboard side of the throttle body, and notice the round damper there. Just fwd of that, and just below it, you will see a screw. Lift upwards on that screw and the linkage will come off the fast idle cam and the linkage will be where it should be when the engine is fully warmed up.

The output of the tps is thru that pin that sits by itself, and runs to the ECU thru the green/red wire that is attached to it on the mating connector.

The brown/white wire should read approx 5vdc.

I can't explain why your voltage on the output wire is not RISING when the screw is turned inward, unless the tps is fouled up.

slimjim16

my tps must be fucked up then, cause i get .09 all the way screwd in and .21 all the way out