really confused on how to set tps....

[noslow5_0]

ok, trying to get to the bottom of my freakin idle surge problem... Ive boiled it down to either the iab which is new, or the tps, which isnt new but will hold a steady voltage... Will someone please tell me the proper way to set a $U#% tps??? I did a search an found about 20 different ways. Ive seen a few that are like this http://www.corral.net/tech/maintenance/idlereset.html
and i tried a way meantioned by Micheal Yount i beleive that i found in a different post.. Anybody... this surging is kickin my @$$

 

[Mavrick]

You want to adjust your TPS with the key on, engine off (KOEO).

Losen the two philips screws holding the TPS in place. With a digital multimeter, you want to stab the GREEN wire with the positive probe, and the BLACK wire with the negative (ground, or common) probe. To make this easier, stab safety pins into the wires, and use the safety pins to make contact with your multimeter probes, its much easier. You should then get a reading. The TPS is pretty sensative, you shouldn't have to move it much. You want to adjust it to ~0.95v. Whatever you do keep it below 1.0v. Tighten those screws back down to put the TPS in place, and test again to make sure it's still in the setting you put it to.

 

[noslow5_0]

yup done that one goin on about the 1000th time.... Seems like everytime i reset the computer it idles just like i want it too, no hanging idle, no surging nuttin for about two days... then BAAM its back... ive been using a .002 feller guage to adjust the throttle stop screw with, and went with a .003 along with a 1/4 turn then did the koeo tps setting procedure... let it sit for awhile an started it back up... nuttin. Maybe it was cause i didnt let it sit long enough??? O well i guess ill see tommorow morning since i disconnected the battery. All this could have been avoided if my dad would have never messed with my throttle stop screw..

 

[noslow5_0]

that reminds me... when my dad first started messing with the throttle stop screw he did turn it down quite a few times... Maybe i will try the whole disconnect the iab valve and set the idle an tps... last time i disconnected the iab the motor just died... stupid e cam from what i heard can be the cause of this but dont know....

 

[noslow5_0]

bump...

 

[jerry beach]

Take off your throttle body and clean it really well. Dont get any carb cleaner in your TPS. If the surge is still there, look at you 10-pins. Pull the codes from you computer first, this may tell you something. If you are mass air, clean the little wires in the MAF housing, this can cause probs.

 

[noslow5_0]

well i guess i should state all that i've done to try an cure the surging:cleaned throttle body and upper intake when i pulled upper off to polish it out, new iac, idle air adjuster kit from ford, ive adjusted the tps and throttle stop screw about 12 thousand times... the only thing thats left is the 10 pin connector, but would that really cause it to surge?? I have an off road h pipe, an no air pump. Ran the codes an before i fixed the fuel pressure, i was gettin 44 an 94 which was the thermo... An then i fixed fuel pressure now im gettin 02 signal code... Dont know whats goin on. Im gonna get a new iac again an see what happens..

 

[NoMod88]

It has been my experience, and I have owned a few 5.0s, that many people seem to think that the TPS is great villain or hero in the Mustang idle surge problem. I have never seen proof of this. These things are just touchy sometimes. You have to methodically go over it and treat it as a total system. They're very susceptible to dirt and vibration. These guys had some good ideas. Clean everything throttle body,EGR valve, etc. Check thoroughly for vacuum leaks and loose connections. Also consider O2 sensors and BAP/MAP sensor. It's hard to say on a modified engine, but with a stock 5.0 the TPS is a replace not a repair item. It is either good or bad (rarely any in between)

 

[jerry beach]

What year is your car. You didnt mention if you cleaned the MAF sensor or not. I have heard the O2 sensors can cause idle surge, but I dont have any personal experience to go on. Just what I read, and have been told. I suggest you get "Ford Fuel Injection and Electronic Engine control" By Charles O. Probst. This is your best bet, follow the step by step troubleshooting in the book. IMO, you will have to resolve the 02 code before you continue to chase the surge demon. Buying new parts in hopes of getting lucky is not cost effective, and wastes alot of time. I would not buy another IAC. You prolly have 2 good ones already, as I do. I have two of everything except the o2's, I got sick of buying stuff, so I bought the book and started learning. You will also need a high impedence Digital Mutimeter, preferably with analog capability. They are around $100 for a good one, but they pay for themselves quickly.

 

[noslow5_0]

its a 90 with pro-m bullet 75 mm triple cleaned.....

 

[PRO50SC]

If you have fooled with the base idle screw this could be the whole problem. Hear is the proceedure for the base idle and then setting the TPS. You have to have a volt meter to adjust the tps to the proper setting. The throttle blade has to be set for the base idle first. With the engine warm disconnect the harness to the iac motor. If the base idle is set correctly it should idle @ approx. 700rpm's. If not, adjust the idle screw on the t/b to the correct rpm. Now with the engine still running, connect a volt meter. Black to groung and red to the tps signal wire. Maybe green depending on year. The other 2 wires are ground and your 5 volt reference. rotate the tps until you acheive .95 -.99 of a volt and tighten down the screws. Now plug in the iac motor and if that's functioning properly the car should idle normally. Hope this helps. You must adjust the base idle first before the tps adjustment!!! Also I had a similar problem but it turned out to be the NEW 75mm pro m bullit mas air I put on it. I put the old one back on and guess what, no more problem. Give it a try