setting throttle position sensor for correct voltage

greaseyfingers · Dec 25, 2007

I would like to check my throttle position sensor to see if it is set to the correct voltage...

can someone explain this procedure, in detail, and what the correct voltage should be, when checking it with a volt meter...

which wires do you check, on the throttle position sensor, while doing this procedure... I'm assuming you must have to, probably, have to back probe them... is that a correct assumption...

I want to do this on my 87 ranger 4x4, model STX, 5 speed tranny, 2.9 liter engine...

holyford86 · Dec 25, 2007

Set your volt meter to 0-2 volt setting, ground it to the battery, backprobe the center pin at the tps and set it to 0.92-0.95 volts using the screw on the throttle body. thats it.

IMenriched · Dec 26, 2007

holyford86 said:
Set your volt meter to 0-2 volt setting, ground it to the battery, backprobe the center pin at the tps and set it to 0.92-0.95 volts using the screw on the throttle body. thats it.

What screw?? or more appropreately which screw?

Is the TPS still attached to the throttle body when doing this?

greaseyfingers · Dec 26, 2007

holyford86 said:
Set your volt meter to 0-2 volt setting, ground it to the battery, backprobe the center pin at the tps and set it to 0.92-0.95 volts using the screw on the throttle body. thats it.

to backprobe the center pin, at the tps, like you said... I'll need to poke a hole through the tps center pin's wire's insulation, right...

should I put a dab of silicone over the hole in the tps center pin's wire's insulation, after I've got it adjusted to the correct voltage setting, 0.92-0.95 specifications...

2manyfords · Dec 26, 2007

Rather than disturbing the insulation just get an old saftey pin a poke it up into the back side of the conector a long side of the centre wire. It will go in about an inch or so.

holyford86 · Dec 26, 2007

2manyfords said:
Rather than disturbing the insulation just get an old saftey pin a poke it up into the back side of the conector a long side of the centre wire. It will go in about an inch or so.

Forgot to mention that :icon_thumby:

Ranger5.0 · Dec 26, 2007

is it not possable to adjust the TPS by losening the screws? the two tps's i have lying around have one round hole, and one sloted one.

holyford86 · Dec 26, 2007

Ive never seen any like that but I doubt it because the tps would have to "swing" to be adjusted like that, adjusting the tps baseline screw on the throttle body on the opposite side will do the same thing, and is much easier.

Ranger5.0 · Dec 26, 2007

its easier? and you havent seen a TPS like that? I have three lol, two on my tool box and one on the truck.

Bob Ayers · Dec 26, 2007

holyford86 said:
Set your volt meter to 0-2 volt setting, ground it to the battery, backprobe the center pin at the tps and set it to 0.92-0.95 volts using the screw on the throttle body. thats it.

You shouldn't use the battery negative terminal as a ground. You should use the GND wire at the TPS, for an accurate voltage reading.

Psychopete · Dec 27, 2007

Ranger5.0 said:
its easier? and you havent seen a TPS like that? I have three lol, two on my tool box and one on the truck.

A friend of mine and I had this conversation about 6 months ago.

As far as the 2.9L TPS, I don't recall a slot to adjust it. I will have to double check, but I really don't think it does.

As far as a 5.0L HO, my friend kept telling me he set is base idle by adjusting the actual TPS via. slot.

Pete

Edit:
Forgot to answer some questions.

The screw he is referring to is on the other side of the throttle body, near where the throttle cable hooks up under the plastic guard. Looks like an idle adjustment screw - moves the butterfly in the TB, phillips I think, can't miss it.

You also don't need to remove any wire enamel. I can usually sneak the volt meter lead along the wire into the plug and press it against what the wire is crimped to inside of the plug. You do not need to remove anything, just turn your key on run, and test it as it sets.

Not all wiring configurations are the same on all 2.9L TPSes. Mine '88 had 2 part #s, I picked a random one, and picked the wrong one. I noticed that it had an (A,B,C) labeled inside where the plug connects into the TPS. The A,B,C configurations differed, I didn't look further, but it was apparrent that the wiring might be slightly different. Just test until you find the ground AND (the 5 volt reference OR computer signal).

Pete

Ranger5.0 · Dec 27, 2007

ya, could be different. When i got my new throttle body, the directions for setting base idle were to first get it runing and warmed up shut the truck off, un plug the tps, start it again and adjust the screw untill a steady 650somthing rpm was reached. Then shut the engine off, plug in the tps and turn the key to the run position. Then backprob the green and orange wires in the conector lossen the screw and adjust the tps to .98 volts.

Hahnsb2 · Dec 27, 2007

You can also adjust it by eyeballing it. I use that screw to bump up my idle when using my on board air, I back it all the way out when I'm done, and screw it back in just enough to barely move the linkage, I've tested it with a volt meter after adjusting like this and it falls right on spec :icon_thumby:

tx_smorgan · Jan 1, 2008

yall are just talking about the tb scew to adjust it or a screw on the tps?

setting throttle position sensor for correct voltage

Member

Some guy with a problem

New Member

Member

Member

Some guy with a problem

New Member

Some guy with a problem

New Member

New Member

Well-Known Member

New Member

New Member

New Member

Sponsored Ad

Sponsored Ad

Today's birthdays

Member & Vendor Upgrades

Truck of The Month

Recently Featured

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals