okay i need expert opinion i took my car to a mechanic because it had been studdering for quiet some time. 2003 audi a4 1.8t. he called me today and told me that someone had filed down the butterfly valve in the throttle body. he said in order to fix the problem he would have to replace the entire manifold and valve because they come pre calibrated from audi. is this true or is he just trying to get me for more money. if so how much does this part cost or can u purchase the butterfly valve alone. if u need more information on my car ask and ill tell i just need this problem fixed thanks.

 

filed down the throttle plate? did they try to port out the cylinders with sand too? get pics, i want to see this. why the hell would you do that?

you probably cant find just buy the plate your talking about, however if you get a junk throttle body from a junk yard or the classifieds, you can swap the plates i believe, although im not 100% sure about you DBW guys. you do NOT need a new manifold unless theres something wrong with that too. the throttle body just bolts on to the intake manifold. no need to replace that unless its damaged. the throttle body is going to be a few hundred bucks. maybe 300 or so new.

i would do a compression test while your at it, if someone was dumb enough to file down the plate, they probably were also lazy enough to do it while still on the car, and metal bits probably got sucked in your engine.

 

i honselty think that my mechanic grinded down the plate. I have pics but am having trouble getting them up on my computer. He has had my car for about a month and was trying to fix my studdering problem. Then all of a sudden said here look at the butterfly plate in the tb and to my amazment it had been grinded down on both top and bottom. I also notice someone had made marking to which side faced forwards on the plate. I talked with a few guys on az and they have been offered a used tb and im only planning on replacing the plate. Now my next question is the mechanic said that the tb is calibrated from factory therefore i would have to replace the entire tb. Is that true or this guy just a damn thief?

 

i cant find a picture of the insides of your TB, but i know on my DBC body theres two screws that hold the plate to the rod that actuates it. you take those two screws out and the plate easily comes out for cleaning. i know atleast on mine they are NOT specialy calibrated. we arent talking about motor itself that moves the plate, just the plate. when you install a new TB you do a TB adaptation anyways which recalibrates the motor in there to the ECU. the metal plate would definately not need to be balanced or any stupid **** like that. hes a thieft, take your car to another mechanic.

if you have an allen wrench and a new gasket you can even install another TB in 15 minuits in your driveway. its even easier then changing your oil, you dont have to jack up the car, its one hose clamp, 4-5 bolts, new gasket between the tb and intake mani, and unplug a cable.

just search on how to do a TB adaptation. basicly you unplug the battery for like half an hour, plug it back in, turn your ignition to ON but dont start the car, leave it like this for a few min, turn the ignition off, then start the car. done.