My fix for Accufab throttle body

[Chipofsc]

My single blade Accufab throttle body has been a problem for me for about a year. It was on the car when I purchased it. Sticking throttle and high idle after WOT was the norm. Tried cleaning it and setting the TPS so many time with little luck. This is the way I fixed it.
Remove the TB and hold it up to the light looking at the blade contact area with the housing. Back out the stop screw so the blade will hit the housing. I used carbon paper to make a mark on the housing where the blade was hitting the housing. I used a dremel tool to remove metal in the area where the blade was hitting. Kept repeating the process until the blade was hitting the same all the way around the housing. Remove the blade and clean the housing and blade to remove any dust. Reinstall the blade but before tighten the screws apply pressure on the blade shaft to ensure the blade is centered in the housing. Hold back up to the light and make sure the blade is centered. Screw in the throttle stop until you have just a small amount of light around the blade. reinstall the TB setting the TPS at .96. I don't disconnect the battery like some people do. My mechanic told me it was better not to. Let the computer learn the new setting. It worked for me. Idle is good and it does not stick. After WOT it will come back down to normal like it should. Accufab throttle bodies are not machined as close as they should be. Hope this helps someone.

 

[joshcarp81]

I noticed the inconsistent gap on mine as well. My idle hangs for a second then drops to highish level. Usually around 900 to 950.
I've tolerated it for awhile but this may motivate me to do something about it.

 

[Chipofsc]

I have noticed the hotter the temp the worst the problem. I have heard the throttle body housing will change size according to the temp. I have the throttle plate very close to the housing but expect I may have to open it up a little later. Mine also idles around 800

 

[sono]

I have KB 168 and it hangs for a second before dropping as well. Dialed in as close as possible but expansion with increased engine bay heat was also an issue.
Interesting regarding the accufab not being machined perfectly. I could see that type of issue being wide spread as well. I have no Idea how perfectly machined the KB is.

 

[1Fast-Turbo-Cou]

Interesting but I kinda find it hard to believe that the Accufab throttle body was machined wrong. Their parts are CNC machined to exact tolerances and they have an extensive QC program. I would call Accufab before modifying ANYTHING. Accufab is a great company and they would be happy to help you.

 

[mattstang85]

Interesting but I kinda find it hard to believe that the Accufab throttle body was machined wrong. Their parts are CNC machined to exact tolerances and they have an extensive QC program. I would call Accufab before modifying ANYTHING. Accufab is a great company and they would be happy to help you.

This^

I had to modify my tps by cutting the mounting holes and use a code reader to clear my codes. My accufab tb was great after that.

 

[Chipofsc]

I did call them and they are very helpful but mine is a older unit and I don't know what all has been done to it. I know when I hold it up to the light you could see where it was touching. It was a simple fix. Accufab offered to calibrate the TB for free but don't know about machining the inside of the TB. If it was a new unit I would have sent it back for sure.

 

[OneSicMystic]

I just installed a new one a week ago and I'm having the sticking. It's pretty annoying when you're putting down almost 500 lol. I'm gonna pull it tonight and do this. Thanks Chip

 

[1Fast-Turbo-Cou]

I asked John about this and Accufab (John) does not recommend modifying the throttle body in anyway, not even adjusting the blade screw. They do not want people messing with them at all for any reason. Also the minute you modify it your warranty (support from Accufab) is probably no existent. At that point it becomes a liability. Accufab will service used/old throttle bodies if they haven't been hacked on. If there is an issue I'm SURE they will make it right. Just call them it only takes a minute..

 

[1Fast-Turbo-Cou]

I just installed a new one a week ago and I'm having the sticking. It's pretty annoying when you're putting down almost 500 lol. I'm gonna pull it tonight and do this. Thanks Chip

Having the sticking? The blade is physically sticking? Or the idle is hanging? Can you be more specific? Also please don't grind on that new TB, figure out what's actually wrong. There is another issue some where.

 

[OneSicMystic]

Feels like the the plate is sticking for sure. This is a known problem with these.
I'm going to pull it off tonight and I'll take pictures of what I find.
Basically, it feels a little "sticky" at normal driving, not really too noticeable but different than my BBK twin 65. When I run car under full boost and let off, next time I go to push pedal it reels like the butterfly is stuck or hung up in the throttle body. I have to push pedal hard to "break it free" and at that point it's like quickly stabbing the throttle to about 50%, which at 500whp is a little brutal lol

 

[OneSicMystic]

Also, when I run the car and shifting between gears it's sticking so it kinda effs up my chi lol

 

[1Fast-Turbo-Cou]

Disconnect the cable and operate the blade by hand, see how it feels.

 

[stangfreak]

The fix has nothing to do with shaving anything off the throttle body. There's hundreds of threads on how to fix this issue. The first problem with the accufab is that, the throttle cam was designed for the 00R cobra. The pedal height is not the same as stock, and if you look at the throttle cable, it kind of starts to come off the cam which causes the short throttle feel when you push it. A member on here a long time ago was selling a kit to adjust the throttle cam and fix the issues.

so glad I was able to buy doug's revised billet flow throttle body. I gave away my accufab to someone for free. I couldn't stand the short throttle feel as well. My friend zee who had a z06 back in the day, when these accufabs were first coming out for the cobra, he drove my car and he even said, why does your car have a short throttle. He drives a vette and was able to tell. He also owned two other mustangs as well. we all had that issue. some don't care, some don't notice it. The height of the pedal also bummed me out. Plus when you hold a accufab next to a billetflow, you can clearly see which one is heavier duty and made better. Revised billet flow > accufab.

Just remembered lol. ED @ RWTD made the drivability mod for the accufab.

 

[stangfreak]

Having the sticking? The blade is physically sticking? Or the idle is hanging? Can you be more specific? Also please don't grind on that new TB, figure out what's actually wrong. There is another issue some where.

exactly. when I removed my accufab there was nothing wrong with the blade or anything making it "stick". physically it was fine.

 

[04cobruh]

Is there a link to the driveability mod? I'm interested.

 

[stangfreak]

Is there a link to the driveability mod? I'm interested.

That was a long time ago. It's no longer available. I will try to see if I can find the thread. I sent that mod to juiced46 on here who had the silver turbo cobra. when we first started to experience all these issues with the accufab, james the mechanic at MUSTANG MAGIC figured all the problems out before all of this was posted on the internet. He was showing me on my car why it creates the short throttle feel, the sticking issue, and why the pedal height changed.

 

[stangfreak]

http://www.modularfords.com/threads/99261-Accufab-Throttle-Body-Drivability-Improvement-Modification

The mod didnt cure the high idle or sticking. we fixed that by adjusting the throttle position screw on my car. But the mod fixed all the other nonsense of the accufab. I know I sound like a broken record but I hated the short throttle feel. when james at mustang magic pushed the throttle cam forward, you can see the cable was NOT making contact with the cam. It would "jump" off. I knew this years before the accufab mod was even developed. we just didnt know how to fix it.

 

[OneSicMystic]

Stangfreak

I did pull the tb Saturday and found some points that were questionable, some gouging. I did take 1000 grit sandpaper and smoothed out a few spots on the blade and the tb itself, not sticking anymore and it idles fine. I ran the piss outta the car too. I have read through all of the threads and this seem to best fit my problem.
I do understand what you're saying but in the end this worked for me. I'll post pictures of what I found soon.
On a side note, I decided to go with the Accufab because a lot of guys seemed to like it and I got one new at a good price....Why the hell hasn't Accufab corrected this issue in the last 12 years?

 

[Chipofsc]

I did talk to John a few weeks ago and he was very nice and took the time to talk to me about all the problems I was having with the tb. I have had this problem for almost a year ever since I purchased the car. John only talked about the stop screw and how important it was not to touch it. He would calibrate the tb for free if I was to ship it to California. I read a post a long time ago where a guy sanded the area the blade was hitting. I just used a die grinder to take off just a small amount. It works great now. So much easier to drive without that sticking and even when running it hard it idles down like it should have when I bought the car. No disrespect to John or to accufab but this worked for me.