? about the tensioner
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
? about the tensioner
The tensioner pulley on my '85 moves up and down and seems to be effecting my idle. I checked the bolt and its not loose, so does mean i've got a broken tensioner?
Race Director
Joined: Jun 2004
Posts: 13,961
Likes: 707
From: WI
It sounds good then, unless your idle changes randomly, that would be another problem. As the idle changes the tensioner keeps the slack out of the belt, it tensions it. If it did not move the belt could jump or slip, as it would get very loose.
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
well now I have a dirty hand! I can push mine down by hand but it takes a lot of effort.Use a 1/2" breaker bar and drop the belt off and see if you have full range on the tensioner.I would have thought it works or doesn't,no halfway.
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Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
The tensioner will go down enough by hand to remove the belt but wont go the rest of the way without the aid of a breaker bar. It will go back into place when I let it go so I guess its good then. I just cant understand why i'm having so much trouble with the freaking idle.
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
well thats another bag of worms.I'd start by trying to establish if it's fuel related or electrical.Idle speed is controlled by the computer.Start searching the posts buddy,there's plenty of them!!
Heel & Toe
Joined: May 2007
Posts: 21
Likes: 0
From: UT
The tensioner should not move so easily. In my 85 I have a chirping noise coming from the tensioner and as soon as I get my freaking IM problem solved, I will shell out the 115 bucks for a new one. As far as it effecting idle, I doubt it, but it does sound like the tensioner is bad. How is the TPS, and IAC? Have you checked for vacuum leaks? Did it do this before you had your timing issue?
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
I went out and started mine and watched the tensioner, mine moves quite a bit also but I can't move it by hand enough to remove the belt so I'm guessing your tensioner could be needing replacement but I just can't see any way in the world it would affect your idle. You don't have enough mods to set the min. air adjustments the way ski_dwn_it recommends so I guess I would start looking for a vacuum leak.
If you do change the tensioner and it solves your idle problem too please post the results here, you may become a hero with a bunch of guys.
If you do change the tensioner and it solves your idle problem too please post the results here, you may become a hero with a bunch of guys.
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Have you cleaned your IAC, reset your minimum idle and TPS per manual spec to verify that isn't the problem? Can you hook your car up to a scanner and see how many IAC counts you are getting at idle?
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Now that I think about it, there are two marks on the housing and one on the tensioner arm. As long as the tensioner arm mark is in between the two on the housing, the tensioner should be good.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
4Ever21, you really got me to thinking about the tensioner changing your idle. It seems logical that if the tensioner is loose enough to unload the belt then the engine would naturally speed up a bit until the IAC brought it back down. That being in my mind I went to Vette2Vette this morning and was able to get a super low mileage tensioner. My tensioner was moving almost 2" so I knew it was weak. I put the good used one on and believe it or not my idle actually started behaving the way it should. Now I'm going to be the first to say that this seems strange and unlikely but I have been fighting my idle now for quite some time and I was blaming the BBK throttle body. I now have my flame suit on for the non-believers and that's okay I may be wrong but my idle now only fluctuates 20-30 rpm. Due to threatening weather and helping buddy work on his C6 I haven't had a chance to go out and drive it but I do know that it IS behaving differently with the tighter tensioner. I say that if you can find a good used one to try, go for it and let me know if I'm nuts or if it really does make a difference.