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Rough idle when cold after intake swap

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Old Apr 27, 2009 | 09:41 AM
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Default Rough idle when cold after intake swap

I swapped to a BBK intake last week and had no problems after firing it up the first time, everything worked like it was supposed to. Then I did a long drive down to LA and the next morning the car had trouble finding the right idle, it was surging not too high, maybe just a few hundred RPMs. The next time I started it and it was surging the car actually died, but it started right back up.

After the car is warmed up, it has no problems holding the right idle, even if I have to restart it.

I used the stock gaskets for the swap, and I am using the stock TB. I am not throwing any codes.

Could this just be that I need to tighten down the bolts a bit more? I did have some trouble getting the rears torqued because I had such a hard time getting my hands back there.

Any help is greatly appreciated, thanks!
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Old Apr 27, 2009 | 10:05 AM
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maybe one of the vacuum hoses in the back popped off because it wasnt tight on there? thats where i would look first.
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Old Apr 27, 2009 | 10:37 AM
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I'll try to reach back there and see. I was thinking since it seems to run okay when its warmed up that it could possibly be that the bolts are not tightened enough?
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Old Apr 27, 2009 | 11:15 AM
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Originally Posted by loyolacub68
I'll try to reach back there and see. I was thinking since it seems to run okay when its warmed up that it could possibly be that the bolts are not tightened enough?
Take it for a spin and listen real good for a whistle or whine. Loose bolts or vacuum leak would produce a slight whine.
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Old Apr 27, 2009 | 11:24 AM
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not loud enough some times

did you torque the bolts down in the proper sequence?
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Old Apr 27, 2009 | 12:26 PM
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Sounds like a vacuum leak to me. The gasket on the intake may just have some trash on it causing it not to seal against the heads.
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Old Apr 27, 2009 | 12:34 PM
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Originally Posted by twitchtwice
not loud enough some times

did you torque the bolts down in the proper sequence?
I did, but the rear bolts may not have been torqued enough. Its hard for me to get my hands all the way back there. I'll try to go through the sequence again and make sure everything is real tight. To me it seems that because its idling okay when its warm, that something is expanding and it gets sealed up. Something may need to be a little tighter. Does that make sense?

Should I be putting loctite on these bolts?
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Old Apr 27, 2009 | 03:51 PM
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No Loctite is needed. Just torque them down good and tight and you should be good to go.
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Old Apr 27, 2009 | 04:06 PM
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Originally Posted by bjamick
No Loctite is needed. Just torque them down good and tight and you should be good to go.
Sweet thanks. I'll just run through the torque sequence again and really get on those back ones. It just seems like an intake leak to me since the problem goes away when its warmed up and I am not throwing any codes. At least I hope so, I don't want to go chasing down a vacuum leak.
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