TPS calibration

[8upZR1]

I am about to instal a new TPS and was wondering if there is any sort of calibration that is required. If so, how is it done?

[tccrab]

I found this on the CF:

<snip>
The default IAC positions are "learned" by the ECM over time. A fresh startup after resetting the ECM will cause the car to idle unusually until the normal position is relearned. Also, any improper shutdown (such as a stall) will cause the ECM to reset the learned values, and you will often get a big idle for a few minutes after this.

It is also very important that you have the TPS and idle screw adjusted properly. If you can scan the car when fully warmed up, you should adjust the the stop screw until the IAC closes to around 10 steps at idle. Car must be good and warm to get an accurate adjustment.

Once that is done, adjust the TPS sensor to 0.51v at idle.

<snip>

HTH

T

[8upZR1]

What do you use to scan the computer? Where can I get one? I was un aware that the TPS had an adjustment screw but I will check it out. Thanks for the help.

[Aurora40]

I don't beleive it has an adjustment screw so much as it has some room to move when the mounting screws are loose.

I wouldn't adjust the factory idle stop though.

You could use a mulitmeter to measure the voltage from the TPS. You could either get those pin things to slide into the harness, or Mid-America used to sell a diagnostic harness thing that plugs in inline with the TPS sensor and has wires you can hook your multimeter to.

[A26B]

Originally Posted by 8upZR1

I am about to instal a new TPS and was wondering if there is any sort of calibration that is required. If so, how is it done?

I noticed on your other thread that you had codes regarding the IAC & TPS. Have you tried to adjust your TPS yet (before you replace it)?

Before you replace it, try the following steps;

(1) remove the elec lead, spray some contact cleaner on the contacts in the TPS & connector. Let dry & apply a small bit of silicone grease to the connector pins & the weather seal, then reassemble.

(2) Disconnect the battery for a minute to clear the codes.

(3) If the TPS code resets, look at the TPS position relative to the adjustment slots of the 2 retaining/adjustment bolts. Almost always, a mid-point setting where the TPS is horizontal (not angled up or down) will put the TPS in the proper voltage range. If yours is angled, loosen the 2 bolts & set the TPS level. THIS IS A QUICK, POOR BOY TRIAL IF YOU DON'T HAVE THE PROPER TEST EQUIP AT HAND.

For the MAP sensor; remove the small hose under the MAP sensor that connects to the rear of the plenum. Check the hose for splits or loose fittings on the end connectors. Clean it inside to remove oil (WD40) blow it clean with air & reinstall. This hose can collect oil & block proper MAP sensing. The hose can deteriorate over time from heat & oil causing the ends to not seal properly, creating vacuum leaks. At worst, the hose will blow off if the engine is not started properly, but only requiring reinstallation of the hose.

I would imagine we have all replaced parts & sensors needlessly before determining the real cause. I have a few used, good parts like this in my spare parts.

PS: When you have multiple codes, always start check procedures with the lowest numerical code first. Fixing the lowest will often solve the remainder.

Good Luck

[8upZR1]

Thankyou for the advice. I will try this out immediately. Hopefully this will solve this issue. Concerning the IAC I still do not know exactly what type of scan tool is used for the IAC. The guy wrote "adjust stop screw until the IAC closes to 10 steps at idle." I would love to do this but dont have any scanning equipment. What type and where can I get it?

I forgot to mention that the car runs like A$$ but doesnt throw any codes until higher RPM & WOT, then the codes come up.