I have located the problem of my idle. The TPS connector was loose. Now i tried to reset the min. air. IAC and TPS. However now the idle is at like 1900. The TPS voltage will only go down to 2.6. Am I doing something wrong? any help is appreciated thanks.

 

check these out

http://www.iroczone.com/2009/10/adju...on-sensor-tps/

http://www.iroczone.com/2009/10/adju...ir-idle-speed/

 

yes i did all that as i stated earlier. I am confused as to why my voltage on the TPS will not go lower than 2.6. I previously had it at .51 before i reset the IAC. At that time the car would idle around 1000rpm. but i want it to idle around 700rpm where it is supposed to be. however after readjusting the Min. air., IAC, and TPS, things are messed up now. WHY??? thanks.

 

i tried adjusting it again today with a different scanner and it read the correct voltageat first. then as i was trying to tighten the screws, it spiked to 2.6V w/o the TPS moving at all. I also didn't have the screw even close to being tight so i know i wasn't over tightening it. Sound like a bad TPS?

 

bad tps for sho. and if you have really bad problems adjusting it, since youre going to throw it out anyways, take it off, connect still and slowly go from 0 volts up to 4volts doing the sweep. any erratic jumps or spikes is a bad sensor. if it goes below your reading now, then the throttle body minimum idle screw is way too much screwed it.

To adjust the minimum idle speed. is to jump the a+b terminal under the dash, turn key on-not start, wait 30 seconds, unplug the iac then turn the key to off afterwards. remove the jumper on the a+b terminal from under the dash, start the engine, have somebody hold the brake pedal down and have them shift into drive. adjust the idle to i think 400 rpms by turning the screw on the throttle body and match 400rpm while in drive with brake on. turn the car off. then reconnect the iac. turn the key to on-not start, and test the tps, adjust it to 0.545volts, then with key to off, Disconnect the tan/timing wiring and time the engine to *6 before tdc. turn car off, connect the tan wire(timing wire on the firewall) and you'll notice a big difference in performance. if theres any codes, clear them diconnect battery, however, i typically wait to see if a code comes up, because my computer takes a long time to 'learn" the data from the sensors feedback.

 

If the TPS test OK when not installed it's possible something is causing the throttle shaft to move when tightening the TPS, or something on the TB TPS mounting surface.

Transam85dudeman,
You're the first I've noticed to include disabling the ECM timing control. That step isn't even in the IAC and TPS adjustment Tech Article.

I've mentioned it before, but to date no correction has been made to the article.

Kudos, Dude.

 

ya i goofed, heres the process, im going to edit that..

 

Your reply #5 is correct, doesn't need editting.
What needs to be corrected is the procedure in that image and TGO's IAC and TPS Article to include disabling the ECM timing control (Tan Wire) when setting the minimum air rate.
If the idle needs to changed as when the engine is modified that should be changed in the chip.

When I built my 388 I set the minimum air rate to 450rpm and change the desired rpm versus temperature table to suit the 388's need to idle at a higher rpm.

 

yeah i've heard of the EST disconnect before. My idle was ok before though. It was just a little too high however the TPS was fine. It was only after i reset the IAC and my min. air that i started having issues with the TPS. I'll try pulling it off and inspect it a little closer and maybe start over and adjust the IAC again.

 

It's done to adjust the timing, not the IAC and TPS adjustment. Once the timiong is made at 6* BTDC, then you can reconnect the EST wire and allow the ESC Module/ECM take over the timing, kind of like how a vacuum advance dizzy does.

 

I never stated it was for the IAC, or TPS adjustment but, it is required for the minimum air rate adjustment, it's in the manual as follows:
Like I said i've posted this in the past.

Once you turn the ignition off to adjust the TPS whether the STC is connected or not doesn't really matter. Just don't forget to reconnected when you done.

 

If you turn off the ignition to adjust the settings on the TPS, what electrical current are you going to pick up or measure? Nothing..... The ignition has to be "On" so that there is current to measure. Remember, there is no current traveling through the TPS if the ignition is off.

 

Correction acknowledged "Once the engine is turned off."

 

, R U still heated? Iz everything good now? All righty then.

 

I'm good, nothing to get heated about.

Trueburton, any update?

 

been busy lately. Hopefully an update tommorrow. thanks for the help.

 

I removed the TPS from the TB with it still plugged in and the lowest reading i could get was 2.3V. And then it would cycle smoothly up to 4.9V. This problem only occurred after resetting the Min.Air and IAC though. Or at least thats when i noticed it. I am now adjusting the IAC and MIn Air once more to double check. But sounds like i need a new TPS.

 

I noticed that the TPS voltage was at .54 when the car was running but when the car is off it was 2.6? that ain't right.

 

Well there's the problem. Get a new TPS and then let us know what reading you get with the new one.

 

i got a used one, if you want it, but i recommend a new one from autozone. although the autozone ones, go bad every three years. but thats wear and tear for ya

 

I only buy OEM sensors. Expensive but the best way to go.