Throttle position on S-AFC onl showing 85%

[WhyteSpyder]

Today I go WOT on second and third gear and my S-AFC only shows 85% open throttle. As I understand, it's suposed to be 100% when you go WOT. Could this be the cause of me only boosting 12 psi and if so how should I go about adjusting it. Is there any adjusting screw or just tighten up the throttle cable?

 

[nine5raptor]

The afc only guesses at what your throttle position is based on tps voltage. I assigns the min. value it sees at 0% and the highest it sees as 100%.

Do you have something like a pocketlogger that will read it correctly?

Also, pull the tb elbow off and look at the valve as someone holds it to the floor and see if it is opening all of the way.

 

[WhyteSpyder]

No I do not have a pocketlogger but am looking for one. Where can I get one for a reasonable price?

 

[kyle]

Thats not something you shop around for http://www.pocketlogger.com/

 

[kpt4321]

Sweet, if your name is Kyle you're awesome.

Have someone floor the gas pedal, and then while they are holding it down, go under the hood and see if you can manually turn the throttle body shaft any more.

What does the SAFC say at idle?

....Kyle T.
93 TSi AWD "TURBO4"

 

[WhyteSpyder]

Originally posted by kpt4321
Sweet, if your name is Kyle you're awesome.

Have someone floor the gas pedal, and then while they are holding it down, go under the hood and see if you can manually turn the throttle body shaft any more.

What does the SAFC say at idle?

....Kyle T.
93 TSi AWD "TURBO4"

S-AFC shows 0% throttle at idle. Can I even floor the pedal sitting there, and do I do this while in gear or in neutral?

 

[ChicagoGSX]

Do it with the car off.

 

[kpt4321]

You could do it with the car on, but it might be hard to concentrate on holding the throttle open manually with the motor bouncing off the rev limiter and jumping around on its mounts.

That's a little too much "livin' on the edge" for me, so I do it with the car off.

Oh yeah, and it you do it in gear, then whoever is stuck standing in front of the car manually working the throttle probably will hate you forever. And they'll want their legs back.



...Kyle T.

 

[WhyteSpyder]

Ok, I have my brother floor it with the car off and I can not open the throttle plate anymore. Maybe the S-AFC is not giving me a correct reading on the throttle position. Thanks for the help guys.

 

[Enraged78]

You're TPS might be off. Test and calibrate it using the shop manual and a volt meter. And it is very possible that you are only hitting 12PSi because of this. I had this exact problem and the car felt like a different animal after I finshed. Do a intake leak test when you are finished, and you should be running well.

Matt.

 

[jonnygsx]

I've noticed that with my pocketlogger I only get a 97% full throttle reading. Any reasons you can think of that might cause this? Is it normal to be a "little" off? How can I adjust the TB if it need be?

Jon

 

[jonnygsx]

sorry double post

 

[nine5raptor]

Originally posted by jonnygsx
I've noticed that with my pocketlogger I only get a 97% full throttle reading. Any reasons you can think of that might cause this? Is it normal to be a "little" off? How can I adjust the TB if it need be?

Jon

that's normal. It doesn't really matter what the sensor reads as long as it is >90%. No one can manufacture a perfect sensor everytime and parts wear out, so there is some slop programmed into the ecu. It will still see it as WOT.

 

[spyder20]

nine5raptor is right....as long as its within a few %, you're fine....mine was sitting at 76% when I got my logger...so I took the tb off and sure enough, I was loosing valuable air...adjusted it and now I'm at 97-98% WOT.....

you should check your sensor as stated earlier

good luck

 

[tsi_turboawd]

mine is at 99.6% at WOT but i heard anything over 80% is already in closed loop.

 

[THEDUKE]

I had this problem when I installed my AFC . I turned the key on with engine not running & pushed the gas pedal to the floor & released it about five times & then turned the key of & when I started it up the AFC was showing 100% after that.