Skunk2 Throttle Body Sticking?!
#1
Skunk2 Throttle Body Sticking?!
Good Evening
I recently installed a Skunk2 TB. All working fine and lovely as you would expect. Done a track day and 200 road miles.
But it has developed the 'sticking problem' Which seems to be overly common with this series of TB from Skunk2.
It only seems to stick when the car is running. Well this is the only time I can get it to do it.
When your on light throttle just cruising at one speed when you come to a stop the idle is sitting at 1500-2000 rather than 1000. A quick blip of the throttle and its fine. The TPS values show it also sticks open slightly.
Has anyone else had them problem?
Things I have checked.
I loosen off accelerator cable so it was slack to rule this out. - Same Problem
Pushed the TB plate stop in slightly just in case it had come loose slightly - Same Problem
sprayed it with WD40/GT85 around the spring area. - Same Problem.
Options I have been reading about. But not check/done
Check TB nut on cable pulley as possible over tighten from factory and causing a slight binding / sticking.
Wind idle stop screw in more so the TB plate sits open rather than totally closed. (May require adjustment on MS for ICV)
^^ Not what I want to do. As it's seems bit of a band aid fix.
When looking at the butterfly there are no marks to show it will stick. Even pushing the pulley back and forth just in case it's moving slightly and then sticking.
I'm sort of at a loose end. With the only real option of seeing about a replacement. But doesn't mean it will fix it.
But going off plenty of forums. This has been a problem for years and people are still reporting the problem.
Hope someone can help & advise!
I recently installed a Skunk2 TB. All working fine and lovely as you would expect. Done a track day and 200 road miles.
But it has developed the 'sticking problem' Which seems to be overly common with this series of TB from Skunk2.
It only seems to stick when the car is running. Well this is the only time I can get it to do it.
When your on light throttle just cruising at one speed when you come to a stop the idle is sitting at 1500-2000 rather than 1000. A quick blip of the throttle and its fine. The TPS values show it also sticks open slightly.
Has anyone else had them problem?
Things I have checked.
I loosen off accelerator cable so it was slack to rule this out. - Same Problem
Pushed the TB plate stop in slightly just in case it had come loose slightly - Same Problem
sprayed it with WD40/GT85 around the spring area. - Same Problem.
Options I have been reading about. But not check/done
Check TB nut on cable pulley as possible over tighten from factory and causing a slight binding / sticking.
Wind idle stop screw in more so the TB plate sits open rather than totally closed. (May require adjustment on MS for ICV)
^^ Not what I want to do. As it's seems bit of a band aid fix.
When looking at the butterfly there are no marks to show it will stick. Even pushing the pulley back and forth just in case it's moving slightly and then sticking.
I'm sort of at a loose end. With the only real option of seeing about a replacement. But doesn't mean it will fix it.
But going off plenty of forums. This has been a problem for years and people are still reporting the problem.
Hope someone can help & advise!
#2
Very common. Take the throttle cable wheel off, drill a new spring hole a little past the current one and the same size, then reinstall. You'll have a barely noticeably stiffer throttle pedal and no sticking.
It may take a few holes to get it right though. It'll be like ~1/8-3/16" away from the current one. Small changer.
It may take a few holes to get it right though. It'll be like ~1/8-3/16" away from the current one. Small changer.
#3
Very common. Take the throttle cable wheel off, drill a new spring hole a little past the current one and the same size, then reinstall. You'll have a barely noticeably stiffer throttle pedal and no sticking.
It may take a few holes to get it right though. It'll be like ~1/8-3/16" away from the current one. Small changer.
It may take a few holes to get it right though. It'll be like ~1/8-3/16" away from the current one. Small changer.
I will have a look.
Does seem very annoying you have to modify such an expensive unit because they can't do the job right first time.
#5
I have found the problem.
well to what I believe is the problem as there is no way the butterfly will stick.
but in the TB pulley where the spring sits there is digs marks of where the spring has been rubbing in the housing.
photo below.
This is no doubt due to when the spring binds up when at WOT it's being pushed out slightly and digging in.
When the thottle is then then closed its grabbing in the groove slightly and not shutting as the spring isn't strong enough to overcome the groove.
So I'm going to remove some material from the inside to see if it fixes the problem. If not... I'm drilling a bloody hole!
but thought I try this.
well to what I believe is the problem as there is no way the butterfly will stick.
but in the TB pulley where the spring sits there is digs marks of where the spring has been rubbing in the housing.
photo below.
This is no doubt due to when the spring binds up when at WOT it's being pushed out slightly and digging in.
When the thottle is then then closed its grabbing in the groove slightly and not shutting as the spring isn't strong enough to overcome the groove.
So I'm going to remove some material from the inside to see if it fixes the problem. If not... I'm drilling a bloody hole!
but thought I try this.
#7
Little update.
My method did bugger all and still does it.
We had a further look into it and it seems to be the springs are not strong enough. As it's the engine holding the butterfly open due to the port speed. Just enough to raise the idle.
It doesnt do it when the car is off so so it tells us it has got to be the port velocity of the air Just forcing it open .
this is only when you lightly take your foot off the throttle from say 2000-2500rpm (coming to a stop)
it sticks at 1500-2000. where if you snap your foot off it fully closes. Or blip the throttle.
so out came the drill. I drilled 2 holes around 3mm apart so I had a few options if it still did it.
ITS FIXED.
this was on the first hole being 3mm further round.
Still thanks for your advise! 👍🏻 Stop me going crazy at such a overpriced bit of kit that doesn't even do the job out of the box.
Thank you @curly
My method did bugger all and still does it.
We had a further look into it and it seems to be the springs are not strong enough. As it's the engine holding the butterfly open due to the port speed. Just enough to raise the idle.
It doesnt do it when the car is off so so it tells us it has got to be the port velocity of the air Just forcing it open .
this is only when you lightly take your foot off the throttle from say 2000-2500rpm (coming to a stop)
it sticks at 1500-2000. where if you snap your foot off it fully closes. Or blip the throttle.
so out came the drill. I drilled 2 holes around 3mm apart so I had a few options if it still did it.
ITS FIXED.
this was on the first hole being 3mm further round.
Still thanks for your advise! 👍🏻 Stop me going crazy at such a overpriced bit of kit that doesn't even do the job out of the box.
Thank you @curly
Last edited by Lawone; 05-17-2017 at 05:29 AM.
#8
I wasn't going to say anything, but yeah, I didn't think your method was going to do anything.
I don't think a strong spring would do anything, it literally has zero preload right when the throttle is closed, by adding a little spring load, it's trying to close the throttle to -5-10%, rather than trying to close to 0% (+/-1%). Go ahead and try your other hole (+6mm), you won't want a stronger spring with that preload!
The S2 throttle body is a little bit of work out of the box, some loctite here and there, I also use longer mounting allens, but once you're done it works ok. I've always had more issues tuning idle with one, but that might also be due to the lack of a good factory bypass setting.
I don't think a strong spring would do anything, it literally has zero preload right when the throttle is closed, by adding a little spring load, it's trying to close the throttle to -5-10%, rather than trying to close to 0% (+/-1%). Go ahead and try your other hole (+6mm), you won't want a stronger spring with that preload!
The S2 throttle body is a little bit of work out of the box, some loctite here and there, I also use longer mounting allens, but once you're done it works ok. I've always had more issues tuning idle with one, but that might also be due to the lack of a good factory bypass setting.
#12
Edit: Here is a pic of the piece you guys drilled. I am assuming the hole should be in the spot I marked in red so it creates more tension on the spring. Please confirm.
Last edited by LukeG; 09-11-2017 at 08:56 AM.
#13
I wasn't going to say anything, but yeah, I didn't think your method was going to do anything.
I don't think a strong spring would do anything, it literally has zero preload right when the throttle is closed, by adding a little spring load, it's trying to close the throttle to -5-10%, rather than trying to close to 0% (+/-1%). Go ahead and try your other hole (+6mm), you won't want a stronger spring with that preload!
The S2 throttle body is a little bit of work out of the box, some loctite here and there, I also use longer mounting allens, but once you're done it works ok. I've always had more issues tuning idle with one, but that might also be due to the lack of a good factory bypass setting.
I don't think a strong spring would do anything, it literally has zero preload right when the throttle is closed, by adding a little spring load, it's trying to close the throttle to -5-10%, rather than trying to close to 0% (+/-1%). Go ahead and try your other hole (+6mm), you won't want a stronger spring with that preload!
The S2 throttle body is a little bit of work out of the box, some loctite here and there, I also use longer mounting allens, but once you're done it works ok. I've always had more issues tuning idle with one, but that might also be due to the lack of a good factory bypass setting.
#15
Not to revive a dead thread but I installed one of these at the same time I installed a MS3... couldn’t figure out if I had a huge vacuum leak or what. Finally realized the TB wasn’t shutting.
I did as the photo above shows and was still sticking so i went all went to about the 5 o clock position and put a hole and it appears right this minute I am fixed. Can finally tune for idle now.
As noted above, I just recently purchased mine, and all 4 bolts were the same length. They bottom out on the upper and lower right side of the intake manifold as those 2 bolts don’t go clear through. My IACV bolt for the plate they send also was to long. I contacted Skunk2 and opened a ticket and they took a week to get me any response and when they did, they awknowledged the issue but offered zero resolution so I just ended up filling them down but just goes to show how shitty these are made and how shitty Skunk2 as a company is.
Regardless, thanks to you guys for the thread, saved me a bunch of time. Think next time I’ll use a ford throttle body 😂
I did as the photo above shows and was still sticking so i went all went to about the 5 o clock position and put a hole and it appears right this minute I am fixed. Can finally tune for idle now.
As noted above, I just recently purchased mine, and all 4 bolts were the same length. They bottom out on the upper and lower right side of the intake manifold as those 2 bolts don’t go clear through. My IACV bolt for the plate they send also was to long. I contacted Skunk2 and opened a ticket and they took a week to get me any response and when they did, they awknowledged the issue but offered zero resolution so I just ended up filling them down but just goes to show how shitty these are made and how shitty Skunk2 as a company is.
Regardless, thanks to you guys for the thread, saved me a bunch of time. Think next time I’ll use a ford throttle body 😂
#18
The S2 throttle body is a little bit of work out of the box, some loctite here and there, I also use longer mounting allens, but once you're done it works ok. I've always had more issues tuning idle with one, but that might also be due to the lack of a good factory bypass setting.
Also, which allens do you suggest using longer ones for, the TB to the IM?
Thanks! The quality and readiness of aftermarket parts is so frustrating. But I don't want a broken throttle plate (I've seen the aftermath first hand!) or an ingested screw so I had to get the S2.
#19
Essentially everything except the bypass screw (you obviously need to be able to adjust this), and throttle plate bolts (never touch those). I use blue for all the loctiting.
I've installed a few lately that have had decent hardware, your results may vary. Just snug every throttle body to intake manifold bolt one at a time without the gasket. If you can still wiggle the throttle body, then the screw is too long. I have a drawer full of various lengths and sizes of SS metric allen bolts available to me, so unfortunately I can't tell you the exact length for all of this.
The only other problem spot besides the spring hole mentioned above, the loctiting, and the TB to IM bolt lengths is the IAC adapter bolts. For a while there was one with the NB adapter that wasn't even sticking out past the gasket, so I had to lengthen it. IIRC in one of the locations I could just reuse the stock screw, but again I would just grab the appropriate one from the hardware drawer and loctite it in.
Hope this helps, thanks everyone for the shout out. The amount of time I wasted trying to tune the sporadic idle before I found this issue was insane, so good to now know what it was.
I've installed a few lately that have had decent hardware, your results may vary. Just snug every throttle body to intake manifold bolt one at a time without the gasket. If you can still wiggle the throttle body, then the screw is too long. I have a drawer full of various lengths and sizes of SS metric allen bolts available to me, so unfortunately I can't tell you the exact length for all of this.
The only other problem spot besides the spring hole mentioned above, the loctiting, and the TB to IM bolt lengths is the IAC adapter bolts. For a while there was one with the NB adapter that wasn't even sticking out past the gasket, so I had to lengthen it. IIRC in one of the locations I could just reuse the stock screw, but again I would just grab the appropriate one from the hardware drawer and loctite it in.
Hope this helps, thanks everyone for the shout out. The amount of time I wasted trying to tune the sporadic idle before I found this issue was insane, so good to now know what it was.
#20
Essentially everything except the bypass screw (you obviously need to be able to adjust this), and throttle plate bolts (never touch those). I use blue for all the loctiting.
I've installed a few lately that have had decent hardware, your results may vary. Just snug every throttle body to intake manifold bolt one at a time without the gasket. If you can still wiggle the throttle body, then the screw is too long. I have a drawer full of various lengths and sizes of SS metric allen bolts available to me, so unfortunately I can't tell you the exact length for all of this.
The only other problem spot besides the spring hole mentioned above, the loctiting, and the TB to IM bolt lengths is the IAC adapter bolts. For a while there was one with the NB adapter that wasn't even sticking out past the gasket, so I had to lengthen it. IIRC in one of the locations I could just reuse the stock screw, but again I would just grab the appropriate one from the hardware drawer and loctite it in.
Hope this helps, thanks everyone for the shout out. The amount of time I wasted trying to tune the sporadic idle before I found this issue was insane, so good to now know what it was.
I've installed a few lately that have had decent hardware, your results may vary. Just snug every throttle body to intake manifold bolt one at a time without the gasket. If you can still wiggle the throttle body, then the screw is too long. I have a drawer full of various lengths and sizes of SS metric allen bolts available to me, so unfortunately I can't tell you the exact length for all of this.
The only other problem spot besides the spring hole mentioned above, the loctiting, and the TB to IM bolt lengths is the IAC adapter bolts. For a while there was one with the NB adapter that wasn't even sticking out past the gasket, so I had to lengthen it. IIRC in one of the locations I could just reuse the stock screw, but again I would just grab the appropriate one from the hardware drawer and loctite it in.
Hope this helps, thanks everyone for the shout out. The amount of time I wasted trying to tune the sporadic idle before I found this issue was insane, so good to now know what it was.