foild

hey guys,
im looking for the best way to test my s4 TPS for idle issues.
i have a great multimeter.. very high quality.

i know its been covered before... but most of the post say search .. and i have.. but all i find is more posts saying search for the tps adjust thread - lol

anyways.. i know its a simple question for lots here... so please help if yah can...
a walk through would be much appreciated.. as i am a beginer.

thanks again
cam

The Spyder

iTrader: (8)

NA, turbo?

Pretty simple, for the MM adjustment, warm car to operating temp, unplug the TPS (remove intercooler on a TII),, and connect the MM leads to the black and green wires. I would suggest sticking the probes in from the back side, so they stay. With the MM set to OHM, sitting there it should read 1ohm. If its not, adjust the set screw until it is. Pull on the throttle, the MM should read a clean swoop from 1- 5ohms + or - 1 ohm. Anything above 6 in my experiance has shown hesitation at the high end and needs replacment.

Chuck

iTrader: (2)

Actually, if you really want to test the TPS function throughout it's range, the best way to do it is to hook your meter up to the TPS pin out at the ECU. Engine at idle fully warmed up should show 1 volt. Engine off with key on max at WOT should be between 4.5 and 6 volts. Depress the throttle slowly and watch the meter. Voltage should progress smoothly from 1V to max without any drop offs. While you're there, you can also test lots of other motor functions. Getting to the ECU is a bit of a PITA though.

foild

the spyer ----- is this done with the car on??
or just with the key turned so that it powers up the car?

so im assuming i unplug the TPS, and there is a connector there that i can touch some prongs on, or like you said push it in the back of the connector?

The Spyder

iTrader: (8)

Have the vehical shut off. Key in the OFF position.

Unplug the TPS from the wiring harness.

From the plug that leads back into the TPS, insert the MM probes from the back side (where the wire come out). Take a look and it will amke sence . Aaroncake has a guide on his site I believe.

lake snake

Just checked/set mine from the fc3spro.com site instructions and it solved my cutout proble, and I think that is actually 1k to 5k ohms and they recomend resistance rather than voltage or led setting. See the tech how to tps.

foild

i checked out the fc3spro.com and tried to do it with their instructions but i am confused.. i dotn see any of that **** on my s4..
heres some pics... please try to clarify some of this stuff

foild

heres pics

foild

my question is... the last pic (with the green connector) - is that where i test for TPS resistance with my multimeter
the first pic is something i saw that bothered me.. is this right... or is something boken here...
as you can see, in one pic i have puled it out, and the other i pushed it in as far as possible. ----- wtf is this thing
also, for that adjust screw pic, how do yah get the little plastic thingy off (if its something really easy... dont call me a idiot cause i basically pulled on it, and it didn;t come off, so i stopped trying (since i was @ work @ the time.)

thanks alot,

cam
p.s. if the green connector isn't where i test with the multimeter... where the hell is it on a s4 NA

thanks again

vincentwashere

heres some instructions. i dont even know what that green thing is. heres a pic of how u should do it. with the meter. sorry for the weird *** fonts



stick the positive thing into the green wire. and negative into the black wire and read ur meter. should read 1k i think. in OHMS. and 5-6k with WOT
good luck

foild

cool thanks, but where do i adjust the tps once i found out how much i need to altur it?

foild

and if it is that little cap thing i circled.. how do you get it off? just pull hard? or wtf

vincentwashere

ok if ur tps is not reading the correct ohms. its broken. get a new one. or a used one that works. im not sure what ur talking about adjusting the tps. u can adjust the idle. look at fc3spro. they show u how to adjust the idle.

foild

on fc3spro they show a "long flat head screwdriver to turn the adjustment screw"
that is in the TPS adjustment how to... but i cant find it on my car..

if you cant adjust the TPS, why would they make a write up called "TPS adjustment for 1986-88 turbo2 models

even though i am NA, i am assuming you can adjust it...

vincentwashere

is the idle spec off? what did ur meter show up on the tests?? you can adjust ur tps if the idle is not 1k ohm. if you cant correct it or the WOT spec is off. then uve got urself a broken tps

lake snake

Ok we have the same s4 na and the tps is on the throttle body and attaches with two screws. it is a rectangular part with a round black plunger that go in and out with the throttle movement to tell the computer the throttle position. the screw you adjust is under that little cap you circled just break off the plastic cover you don't need it. with the tps disconnected set it to 1k when closed. you also posted about the temp sensor under the coolant fill cap in the first two thumbnail pics, just replace that. The green connector by the right strut tower isn't involved with either I don't think will check tommorow.

foild

im just wondering.. should i get loaned the money so i can buy it... or can it wait for a few weeks?
(in a few weeks i am getting a engine rebuild.. i can just put it on then

vincentwashere

id just wait. but im not sure what would happen.

foild

ok... i just checked the resistance on the TPS.
it was 1 ohm
that is correct, isn't it?

now my next question is... what else could cause the problems.
i am highly doubting vacume leaks..... but is there any way of checking besides just to look for cracked tubes or whatever?

also, could it be the water thermal sensor, i noticed my is broken.. ???

thanks alot,
cam

The Spyder

iTrader: (8)

If your water sensor is broken, it can put the ecu into limp mode.
What exactly is your car doing?

foild

also, i didn't check what the resistance was like when opening throttle 100%, because that is not where i am finding a problem.. its my idle thats the issue...

and... i do know it was reading the TPS correctly, because i did snap open the throttle just to see what it read, and it did increase so i know i am actualy getting a 1 ohm reading at no throttle.

thanks,
cam

foild

my car is running fine.

only things that occur that are a concern, is at the idle surges a little, and when i take my foot off the gas pedel suddenly, it drops to the little red line @ the bottom of the tach, then quickly bounces up back to normal surging idle.. at 750+ or - RPM

foild

well, i shouldnt say its broken.. i dont know if it is broken.... all i know is that i can pull it in and out of the mount on the filler neck... check the pics on the first page you will see what i meen

vincentwashere

that would be your spark plugs. go check em sounds like its misfiring or not firing at all, same thing happened to me. and one of my sparkplugs the porcilien was cracked
(sorry i phrased it wrong had to redit it)

foild

nah.. brand new spark plugs.
happened before and after replacement