Templeswain

I searched through the tps threads and I'm a little confused.

I'm also following the instructions from the FSM on fc3s.org.

In FSM it talks about testing the throttle sensor from this place by the air box with a check light. Is this green connector the initial set connector?

I was testing the resistence from the tps module itself directly and getting weird readings.

Where do I check the resistence to adjust the tps? Is it really from the tps or from the air box section?

I haven't been able to drive it since messing around with the TPS and making it idle higher than usual. I was able to get the engine to idle at 1200 rpm consistently and was actually happy with that until HAILERS said that an idle that high was a "rampage". So I haven't driven it until I get it to idle at cool 750 rpm.

Any help much appreciated.

Aaron Cake

iTrader: (1)

Don't waste time with the test lights or checking the voltage. If this is an '86-'88, completely warm up then shut off the car and unplug the TPS. Hold the connector with the hump "up" and connect your test leads to the top and rightmost terminal. Set your ohmmeter on whatever scale you can most accurately read 1K on (normally the 2K or 5K scale) and adjust the TPS to show 1K exactly. Plug back in, go for a drive, then repeat procedure.

Templeswain

Thanks Aaron.

Whoops, sorry it probably would have helped to tell you its a 91 N/A with an s4 block in it.

I printed out your instructions on turbonut's page.

I'll try again.

Thanks!

Aaron Cake

iTrader: (1)

My instructions on who's page? I have not yet published my "TPS Setting" page.

Same procedure for the S5, except the two you want to measure are the two upper right on the square connector (clip pointing up)...At least, if I remember correctly.

RustX7

What year is your car? The TPS is different between the 86-88 and the 89-91 years.

If it's an 86-88, check out this picture for the resistance adjustment. This is from the turbo FSM but the TPS is the same, as far as I know.

The resistance is checked at the TPS itself. Unplug it to test. You should be putting the probes of your multimeter on the TPS connector, not on the connector on the harness side. Connect the probes and play with the screw until it reads 1 k-ohm (with the throttle closed.) With the throttle all the way open, that resistance should read 5+/- 1k-ohm as the FSM says.. if it's way out of wack, you may need a new TPS.

Correct me if I'm wrong everyone, but can't the TPS also be adjusted simply by adjusting this resistance? I did mine that way, and that brought my voltages at the check connector to exactly 12V and 0V. On an 86-88 (S4) turbo, the check connector I'm talking about is green and hanging right around the area of the oil filler next.

RustX7

Holy god. Three replies while I was typing. fast!!

Templeswain

Thanks aaron and Rustx7 (lol)

I finnally got her to idle at 750. But it like to fluctuate to 1000 sometimes.

Look like I'll be cleaning the BAC next.

The tps was waaaaaaaaaaay out of adjustment at 3000K

I really adjusted it because the spring in the screw is almost all the way depressed now. The resistance wouldn't go down any other way (???)

Could the TPS still be bad?

RustX7

I really couldn't tell you how far my TPS screw is depressed with the TPS adjusted. I don't think I'm near running out of threads on it though... but then mine is an S4 so I dunno your screw might be different.

If the resistance meets the specs in the FSM and the connector on it is good then I'd guess it's OK.