I had a 52mm throttle body installed a couple months ago, and since then my car has been messing up(SES light before shift in WOT, odd shifting in normal driving, stumble). Does anybody know if it is necessary to reprogram the PCM when upgrading the throttle body? I've replaced the TPS and that didn't help(it is adjusted right). I had a diagnostic ran because of the SES and it returned a MAF code and TPS code. Any help is appreciated.

Steve

 

I would double check that everything is plugged in completely and in the right locations. There is a chance you could have forgot to plug a sensor back in after the install. No, you don't have to reprogram your computer for a bigger throttle body. Are all your vacuum lines either capped or used?

 

I thought when you went to a 52mm TB that you had to reprogram your pcm upping the line pressure so you wouldn't have "soft shifts" which could damage the clutches.

 

Im no way an expert on this stuff--But when my step-son put my 52mm tb on i had the same hard shifting problems, it was tps related-dont know about your other code but i would check again to see if that tps is set up right again. He didnt have mine seated right or something--check your tps voltage again--Good luck--Dwayne

 

I had the throttle body professionaly installed. Also, my car is an A4.

 

This is a quote from Ion at madz28.com


I am about to have some programming done and this came up.

 

an A4 needs reprogramming for a bigger TB

you have to check and adjust your TPS voltage also

jesse

 

How would one go about adjusting the TPS? I've got a Holley.

 

INJUNEER has answered numberous posts about tps voltage, do a search with his name and "tps".

reference voltage is 5V
idle (closed throttle) should be 0.2-0.9V, most ppl like to be around 0.65, mine is 0.76 and no problems.

WOT voltage should be >4V mine is 4.36

the voltage should increase as you increase the throttle.

you will find 3 wires going to your tps, a black, blue and gray one.
i believe the gray wire is for reference, black for ground, and blue for variable voltage. but check INJUNEER's posts to be sure

hope this helps

jesse

 

I wouldn't worry about trying to set the TPS voltage, the computer zeros itself when you start the car anyway. You really should have the computer redone so you don't have to replace the transmission in the near future.

 

interesting, never heard of that....

with my 58bbk, when i first bought it i just cracked the throttle blades to make it idle right. the car would always throw a "tps high voltage" code at WOT. it never learned it, it keep throwing that code until i fixed the tps voltage.....

jesse

 

I have been adjusting my TB since I got off work, and I accidentally dropped one of the screws Can't find it. Does anybody know off hand what size/type it is?

Steve

 

I got some actual screws from the local hardware store when I dropped one of mine. They're a small metric I believe. Don't know off hand at the moment.

 

It will auto adjust so long as the ign on/start up value is in the correct band... and it's a pretty big band So long as your idle voltage is between around .25 and .9 volts (and even outside that a little sometimes!) you shouldn't get a code and the computer will adjust TPP (what the PCM uses) to 0% at blades closed to 100% at WOT. With some other cars it can be important to set the closed voltage at a specific number like .6 volts. With our cars it isn't important because the PCM will auto adjust for the correct TPP.

 

thanks brent

jesse