Installed Ported FAST 90/90..Throttle sticking..AC wont work...wtf?.
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Alright so i just finished installing my FAST 90/90 on my Firehawk..but i have a few issues...
One i had to dremel the little block at the end of the throttle cable just so it would slide inside the throttle bracket on the TB. Now after getting that to work, first drive the car had idle issues but seemed to find itself.
However ...Now the throttle sticks between 900-1400 rpms unless i rev it real fast..then it closes.
As soon as roll out in first gear and tap the throttle it starts going by itself and holds revs untill i tap the real quick and it goes away. Its like its sticking at the point of barely opening. It does this is every gear.
How do i fix this? New Throttle position sensor? Anyone else have this issue?
On tap of that..my AC or fan wont blow threw the vents now.. I removed the AIR pieces from the LS6 intake. Does that have anything to do with it?
-Chris
One i had to dremel the little block at the end of the throttle cable just so it would slide inside the throttle bracket on the TB. Now after getting that to work, first drive the car had idle issues but seemed to find itself.
However ...Now the throttle sticks between 900-1400 rpms unless i rev it real fast..then it closes.
As soon as roll out in first gear and tap the throttle it starts going by itself and holds revs untill i tap the real quick and it goes away. Its like its sticking at the point of barely opening. It does this is every gear.
How do i fix this? New Throttle position sensor? Anyone else have this issue?
On tap of that..my AC or fan wont blow threw the vents now.. I removed the AIR pieces from the LS6 intake. Does that have anything to do with it?
-Chris
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Sounds like the TB blade is hanging. I would take it apart and inspect it. As for the AC vents, sounds like you left off the little vacuum line that goes into the harness, it controls the vacuum actuated vents inside the cabin.
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by removing the air pieces you have no vacuum on the line which goes to the AC so the blend door won't work properly. you'll probably still have floor vents and defrosters but no dash vents.
and did you cap off the vacuum line on for the HVAC line the intake? it almost sounds like you could have just left it open (it's in a difference location on the fast) and that's causing the high idle that feels like the throttle sticking
and did you cap off the vacuum line on for the HVAC line the intake? it almost sounds like you could have just left it open (it's in a difference location on the fast) and that's causing the high idle that feels like the throttle sticking
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The Fast brand 90mm TB are junk.
You will need to mark where the blade is sticking before you remove the tb from the intake. Use some chalk or grease or something. Then remove it and slowly grind/sand with a dremel until it will close properly.
It might not hang when it's off. Mine would only hang and drag once it was bolted on for whatever reason.
You will need to mark where the blade is sticking before you remove the tb from the intake. Use some chalk or grease or something. Then remove it and slowly grind/sand with a dremel until it will close properly.
It might not hang when it's off. Mine would only hang and drag once it was bolted on for whatever reason.
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I didn't have any vacumme line hookups on the back of the FAST except for the brake booster. There was no little needle nose piece for that vacuume line to go on in the back.
Where else can it go?
Where else can it go?
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So you're saying you don't have the little nipple on the rear passenger side of the intake? As shown below:
![](http://xmsengineering.com/images/uploads/AST%20LSX%20Intake%20Manifold%20in%2078MM%20or%2090MM.jpg)
You can see it on the bottom left of this picture. That's a little odd. I'd be interested to see some pictures of your intake. Keep us posted... this is likely a problem if the vacuum line that is supposed to go there is left wide open.
![](http://xmsengineering.com/images/uploads/AST%20LSX%20Intake%20Manifold%20in%2078MM%20or%2090MM.jpg)
You can see it on the bottom left of this picture. That's a little odd. I'd be interested to see some pictures of your intake. Keep us posted... this is likely a problem if the vacuum line that is supposed to go there is left wide open.
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hey I had this issue last week, it was my Smooth Bellow(the rubber piece that goes on the throttle body) the clamp was not on properly, it looked right but air was leaking. I dont know if that helps but worth a try. Just put presure on it with your hands and see if idle changes.
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Alright...i over looked the vacuume line. I capped the open part of the line and connected the other part to the intake.. AC works again... thank god.... lol
However the idle issue is still present. I'm going to take apart the TB. Clean up up, and lightly dremel it, and hopefully get rid of the sticking issue.
I wonder if its vacuume related to?
The sensor at the back of the intake didn't go in tight at all. I had to RTV it. I better check to see if its still good to go.
But let me ask this..with the stock tune...would the car idle funny because of the bigger intake/TB setup??
However the idle issue is still present. I'm going to take apart the TB. Clean up up, and lightly dremel it, and hopefully get rid of the sticking issue.
I wonder if its vacuume related to?
The sensor at the back of the intake didn't go in tight at all. I had to RTV it. I better check to see if its still good to go.
But let me ask this..with the stock tune...would the car idle funny because of the bigger intake/TB setup??
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I've got the same Fast 90 TB sticking problem. For right now the TB has a good ole thottle return spring like you would find on a regular carb added to it. Its worked pretty good so far.
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Alright guys..i took the TB off and apart..cleaned it in and out..dremel it slightly because i could see metal to metal catching inside at the open close area... Then polished the hell out of it. In hand it seemed to be fixed..i put it back on the car and the same problem still....
I'm frustrated as all hell.. i have to throttle it real quick all the time to get the throttle to go back down...its frustrating as ****.
Can i see some pictures of this return spring setup you guys are running on it? I need to fix this ASAP.
I'm frustrated as all hell.. i have to throttle it real quick all the time to get the throttle to go back down...its frustrating as ****.
Can i see some pictures of this return spring setup you guys are running on it? I need to fix this ASAP.