Installed FAST 90 TPIS 90 Tbody...got problems
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From: Okinawa, Japan
Installed FAST 90 TPIS 90 Tbody...got problems i just did new PRC springs 90mm intake and TPIS tbody, got it all together, fiddled with the bellow forever getting that right and then fired it up, didnt want to idle but finally found it at 1100 and idled down to my normal 850 hot, i figured itll learn it.
heres whats weird when the car is off the gas pedal feels different than when the car is on....its sticking or something when the car is on, stuck a couple times and it revved to 5000, yea real good for my brand new springs, so much for heat cycling....anyways i turned it off i can just crack the trottle and it shuts just fine or i can wide open it and it snaps shut like normal. So, i start it back up and just barely touch the gas get it to 1500 and it stays there, i get out and sure enough the blade is open a little bit, so i turn it back off and manually try and get it to stick open a tiny bit with it off and cant do so, is this something VERY weird with the tune or what, i think it screwed my tune up pretty bad i heard a lil pingin on the way home.
a few other things that i need to do, run that tube from the valve cover into the bellow so that air gets metered and need to figure out this sticking throttle deal....help guys, kurt
ps dont give me **** about my run on sentences, ive been ****** with this car all day and im tired
heres whats weird when the car is off the gas pedal feels different than when the car is on....its sticking or something when the car is on, stuck a couple times and it revved to 5000, yea real good for my brand new springs, so much for heat cycling....anyways i turned it off i can just crack the trottle and it shuts just fine or i can wide open it and it snaps shut like normal. So, i start it back up and just barely touch the gas get it to 1500 and it stays there, i get out and sure enough the blade is open a little bit, so i turn it back off and manually try and get it to stick open a tiny bit with it off and cant do so, is this something VERY weird with the tune or what, i think it screwed my tune up pretty bad i heard a lil pingin on the way home.
a few other things that i need to do, run that tube from the valve cover into the bellow so that air gets metered and need to figure out this sticking throttle deal....help guys, kurt
ps dont give me **** about my run on sentences, ive been ****** with this car all day and im tired
Does it stick when there is nothing hooked to the TB? You may need a stiffer spring to get it to shut properlly. You could also try and coil the spring one more turn to stiffin it up. My FAST 90 has 2 spring holes oppisite each other so you can tighten it in 180 degree increments.
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From: Okinawa, Japan
i cant get it to stick when the car is off, when the tbody was off the car in my hands it had no resistance whatsoever, i thought of wrapping that spring one more time,
TTT any more thoughts guys
TTT any more thoughts guys
Jayson had the same issues with my 90mm Tb. We had to drill a hole in the TB and adjust the screw to fix the TB sticking open. Also we had to switch the part that hooks to the throttle cable. Didn`t have much slack in it. I will tell you this. We did have to do some tuning adding the 90mmTB to get it right. He adjusted some things with LS1 edit and it smoothed right out. Car rocks its *** off now. Good Luck!
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From: harrisburg, pa
I had the same problems..do a search..lots of posts..its the shitty shaft..got to tear it apart...thats what Im going to do soon
it has nothing to do with tuning or drilling holes...TPIS junk
it has nothing to do with tuning or drilling holes...TPIS junk
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Verdad Gallardo I actually haven't had a problem with my FAST. I peened the bearings and recessed the set screw into the shaft and everything is fine. I also saved $100 over the TPIS and got to keep my stocker. I don't know why so many people gripe about it. It took me 30 min to not have any problems. Sounds like the TPIS isn't the same.:dunno:
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From: harrisburg, pa
Here is one of our dicussions about TPIS in the external forum:
1. The tiny bearing that is on the TB shaft on the TPS side of the TB was working it way out of it's hole. There is about a 1/4" gap between the back of the TPS and that bearing. So, basicly there is nothing to hold that bearing securely in place. When the bearing would work it's way out of it's slot it would cause "slop" in the TB shaft resulting in a slight binding or sticking open(only at idle) of the TB butterfly. Brian Tooley at TEA took a small center punch and peened the edges of the TB around the small bearing to hold it securely in place. No biggie. You can't see it because the TPS covers the bearing and all. I believe that has been my major problem all along.
2. There are two holes on the throttle cable cam for the cable to fit into. I had mine ('98) in the lower hole. But this hole on my car resulted in almost zero free play in the cable which could, theoretically ,cause the TB butterfly to not close completely. I mean it was super close to not closing all the way.
So, I put the cable in the upper hole but I had to do some slight "sizing" of the cam hole and the cylindrical cable end to get it to fit properly. Now plenty of slack, no probs.
3. The throttle cable cam is secured to the TB shaft with an allen head set screw. During one of my "high idling" episodes, I popped my hood and checked the TB and noticed the The cam was slipping slightly on the TB shaft. I imagine that this was due to the TB butterfly sticking and then the spring tugging on the cam to pull it to it's stop.
So my recommendation would be to take the allen screw out. Mark the shaft through the hole. Remove the cam. Drill a tiny indention for the allen screw to set it. And reinstall everything. Of course if nothing is binding this most likely would not be necessary.
Sam, on your TB, I guess I would recommend checking everything for binding and no slop in the TB shaft. If there is any slop fix that and insure NO binding. Then get the car idling normally at normal operating temp and check your IAC counts with a scan tool or Autotap. They should be around 40. If not try adjusting the set screw that holds the TB butterfly open till you get in that range. You must watch your TPS sensor on the scan tool also to insure you haven't moved the TB butterfly too much. The TPIS reading should show "0" at idle during this process. If the TPIS reading goes above "0" then your computer is reading "acceleration".
If your IAC counts are still way high you will have to drill a small hole in the TB blade; on the top half of the TB blade slightly to the right, nearly in line with the IAC hole in the TB, but not exactly in line with it. After you get the IAC counts where you need them then tune it through the computer.
1. The tiny bearing that is on the TB shaft on the TPS side of the TB was working it way out of it's hole. There is about a 1/4" gap between the back of the TPS and that bearing. So, basicly there is nothing to hold that bearing securely in place. When the bearing would work it's way out of it's slot it would cause "slop" in the TB shaft resulting in a slight binding or sticking open(only at idle) of the TB butterfly. Brian Tooley at TEA took a small center punch and peened the edges of the TB around the small bearing to hold it securely in place. No biggie. You can't see it because the TPS covers the bearing and all. I believe that has been my major problem all along.
2. There are two holes on the throttle cable cam for the cable to fit into. I had mine ('98) in the lower hole. But this hole on my car resulted in almost zero free play in the cable which could, theoretically ,cause the TB butterfly to not close completely. I mean it was super close to not closing all the way.
So, I put the cable in the upper hole but I had to do some slight "sizing" of the cam hole and the cylindrical cable end to get it to fit properly. Now plenty of slack, no probs.
3. The throttle cable cam is secured to the TB shaft with an allen head set screw. During one of my "high idling" episodes, I popped my hood and checked the TB and noticed the The cam was slipping slightly on the TB shaft. I imagine that this was due to the TB butterfly sticking and then the spring tugging on the cam to pull it to it's stop.
So my recommendation would be to take the allen screw out. Mark the shaft through the hole. Remove the cam. Drill a tiny indention for the allen screw to set it. And reinstall everything. Of course if nothing is binding this most likely would not be necessary.
Sam, on your TB, I guess I would recommend checking everything for binding and no slop in the TB shaft. If there is any slop fix that and insure NO binding. Then get the car idling normally at normal operating temp and check your IAC counts with a scan tool or Autotap. They should be around 40. If not try adjusting the set screw that holds the TB butterfly open till you get in that range. You must watch your TPS sensor on the scan tool also to insure you haven't moved the TB butterfly too much. The TPIS reading should show "0" at idle during this process. If the TPIS reading goes above "0" then your computer is reading "acceleration".
If your IAC counts are still way high you will have to drill a small hole in the TB blade; on the top half of the TB blade slightly to the right, nearly in line with the IAC hole in the TB, but not exactly in line with it. After you get the IAC counts where you need them then tune it through the computer.
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From: MI
Originally Posted by SAM98WS6
Here is one of our dicussions about TPIS in the external forum:
1. The tiny bearing that is on the TB shaft on the TPS side of the TB was working it way out of it's hole. There is about a 1/4" gap between the back of the TPS and that bearing. So, basicly there is nothing to hold that bearing securely in place. When the bearing would work it's way out of it's slot it would cause "slop" in the TB shaft resulting in a slight binding or sticking open(only at idle) of the TB butterfly. Brian Tooley at TEA took a small center punch and peened the edges of the TB around the small bearing to hold it securely in place. No biggie. You can't see it because the TPS covers the bearing and all. I believe that has been my major problem all along.
2. There are two holes on the throttle cable cam for the cable to fit into. I had mine ('98) in the lower hole. But this hole on my car resulted in almost zero free play in the cable which could, theoretically ,cause the TB butterfly to not close completely. I mean it was super close to not closing all the way.
So, I put the cable in the upper hole but I had to do some slight "sizing" of the cam hole and the cylindrical cable end to get it to fit properly. Now plenty of slack, no probs.
3. The throttle cable cam is secured to the TB shaft with an allen head set screw. During one of my "high idling" episodes, I popped my hood and checked the TB and noticed the The cam was slipping slightly on the TB shaft. I imagine that this was due to the TB butterfly sticking and then the spring tugging on the cam to pull it to it's stop.
So my recommendation would be to take the allen screw out. Mark the shaft through the hole. Remove the cam. Drill a tiny indention for the allen screw to set it. And reinstall everything. Of course if nothing is binding this most likely would not be necessary.
Sam, on your TB, I guess I would recommend checking everything for binding and no slop in the TB shaft. If there is any slop fix that and insure NO binding. Then get the car idling normally at normal operating temp and check your IAC counts with a scan tool or Autotap. They should be around 40. If not try adjusting the set screw that holds the TB butterfly open till you get in that range. You must watch your TPS sensor on the scan tool also to insure you haven't moved the TB butterfly too much. The TPIS reading should show "0" at idle during this process. If the TPIS reading goes above "0" then your computer is reading "acceleration".
If your IAC counts are still way high you will have to drill a small hole in the TB blade; on the top half of the TB blade slightly to the right, nearly in line with the IAC hole in the TB, but not exactly in line with it. After you get the IAC counts where you need them then tune it through the computer.
1. The tiny bearing that is on the TB shaft on the TPS side of the TB was working it way out of it's hole. There is about a 1/4" gap between the back of the TPS and that bearing. So, basicly there is nothing to hold that bearing securely in place. When the bearing would work it's way out of it's slot it would cause "slop" in the TB shaft resulting in a slight binding or sticking open(only at idle) of the TB butterfly. Brian Tooley at TEA took a small center punch and peened the edges of the TB around the small bearing to hold it securely in place. No biggie. You can't see it because the TPS covers the bearing and all. I believe that has been my major problem all along.
2. There are two holes on the throttle cable cam for the cable to fit into. I had mine ('98) in the lower hole. But this hole on my car resulted in almost zero free play in the cable which could, theoretically ,cause the TB butterfly to not close completely. I mean it was super close to not closing all the way.
So, I put the cable in the upper hole but I had to do some slight "sizing" of the cam hole and the cylindrical cable end to get it to fit properly. Now plenty of slack, no probs.
3. The throttle cable cam is secured to the TB shaft with an allen head set screw. During one of my "high idling" episodes, I popped my hood and checked the TB and noticed the The cam was slipping slightly on the TB shaft. I imagine that this was due to the TB butterfly sticking and then the spring tugging on the cam to pull it to it's stop.
So my recommendation would be to take the allen screw out. Mark the shaft through the hole. Remove the cam. Drill a tiny indention for the allen screw to set it. And reinstall everything. Of course if nothing is binding this most likely would not be necessary.
Sam, on your TB, I guess I would recommend checking everything for binding and no slop in the TB shaft. If there is any slop fix that and insure NO binding. Then get the car idling normally at normal operating temp and check your IAC counts with a scan tool or Autotap. They should be around 40. If not try adjusting the set screw that holds the TB butterfly open till you get in that range. You must watch your TPS sensor on the scan tool also to insure you haven't moved the TB butterfly too much. The TPIS reading should show "0" at idle during this process. If the TPIS reading goes above "0" then your computer is reading "acceleration".
If your IAC counts are still way high you will have to drill a small hole in the TB blade; on the top half of the TB blade slightly to the right, nearly in line with the IAC hole in the TB, but not exactly in line with it. After you get the IAC counts where you need them then tune it through the computer.
I beleave Kurtomac has a TPIS T/B this write up is about a FAST T/B and where it talks about the TPIS reading is a spelling errror and meant to read TPS reading.
Kurtomac I had to add a extra carburator type spring to my TPIS T/B to get rid of the intermitting high idle problem. When I had mine re-dynoed my tuner had to add more fuel for the new amout of air coming in. As far as the valve cover pcv air inlet hose I used a small K&N filter and the pcm learned the unmetered air coming in so that was no problem. So I just think the real problem with the TPIS T/B is a weak throttle spring, I tried to get a extra wrap but there wasn't enough spring to do that.
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From: MI
If you check this thread out https://ls1tech.com/forums/generation-iii-external-engine/247071-what-bellow-tpis-90mm-stock-maf.html
and scroll down to the pic's of my engine you can see where I put my extra spring on.
and scroll down to the pic's of my engine you can see where I put my extra spring on.
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Joined: Dec 2001
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From: MI
Originally Posted by Kurtomac
i ran the hose from the valve cover into my bellow before tunning to make tunning easier(metered air vs unmetered air)
good luck!
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Joined: Jan 2002
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From: MN
call us
Originally Posted by Kurtomac
i just did new PRC springs 90mm intake and TPIS tbody, got it all together, fiddled with the bellow forever getting that right and then fired it up, didnt want to idle but finally found it at 1100 and idled down to my normal 850 hot, i figured itll learn it.
heres whats weird when the car is off the gas pedal feels different than when the car is on....its sticking or something when the car is on, stuck a couple times and it revved to 5000, yea real good for my brand new springs, so much for heat cycling....anyways i turned it off i can just crack the trottle and it shuts just fine or i can wide open it and it snaps shut like normal. So, i start it back up and just barely touch the gas get it to 1500 and it stays there, i get out and sure enough the blade is open a little bit, so i turn it back off and manually try and get it to stick open a tiny bit with it off and cant do so, is this something VERY weird with the tune or what, i think it screwed my tune up pretty bad i heard a lil pingin on the way home.
a few other things that i need to do, run that tube from the valve cover into the bellow so that air gets metered and need to figure out this sticking throttle deal....help guys, kurt
ps dont give me **** about my run on sentences, ive been ****** with this car all day and im tired
heres whats weird when the car is off the gas pedal feels different than when the car is on....its sticking or something when the car is on, stuck a couple times and it revved to 5000, yea real good for my brand new springs, so much for heat cycling....anyways i turned it off i can just crack the trottle and it shuts just fine or i can wide open it and it snaps shut like normal. So, i start it back up and just barely touch the gas get it to 1500 and it stays there, i get out and sure enough the blade is open a little bit, so i turn it back off and manually try and get it to stick open a tiny bit with it off and cant do so, is this something VERY weird with the tune or what, i think it screwed my tune up pretty bad i heard a lil pingin on the way home.
a few other things that i need to do, run that tube from the valve cover into the bellow so that air gets metered and need to figure out this sticking throttle deal....help guys, kurt
ps dont give me **** about my run on sentences, ive been ****** with this car all day and im tired