Installed cold air intake now having idle prob

Snorkus, filters, throttle bodies and intake manifolds.

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Mike801
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Installed cold air intake now having idle prob

Post by Mike801 »

So I have a 91 legacy turbo auto and I just installed an intake with a open air filter and like so many others I went specter anyhow after installing the car will start but it will not stay that way unless I hit the throttle I have checced all vac lines and maf the only thing I can think of is I added a breather filter to the 3/4 hose that leads from the front of the small air box to the intake manifold not sure if that's it bit any input is appreciated. (I'm sure there is something on this already but I can't find it at the moment)
91 Leggy turbo (Enos) Sec owner. 226000 mi and rolling
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kimokalihi
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Re: Installed cold air intake now having idle prob

Post by kimokalihi »

Why the breather filter? Plug it and see if that helps. I don't have the stock intake setup so I am having a difficult time picturing what you're referring to but it sounds like you've introduced a vacuum leak to your intake which will lean out your fuel mixture and that's never good.
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Legacy777
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Re: Installed cold air intake now having idle prob

Post by Legacy777 »

Welcome to the BBS.

The only 3/4" line I'm aware of is the IAC valve. This line needs to be put back to the way it was originally setup. Did you also remove the resonator box that went between the MAF sensor and turbo inlet elbow?

I'd recommend you go back to the stock airbox configuration and just remove the snorkel from the fender well. This does reduce some of the intake back pressure and gives you some intake noise.
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Mike801
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Re: Installed cold air intake now having idle prob

Post by Mike801 »

I did remove the res box the issue was both the stock box was broken and the resonator box was missing most of the posts for the lines to feed into. I am thinking it is the 3/4 line with the breather filter and i also have noticed that the plastic that runs from the intake into two lines leading to the valves had been broken and then rigged together by the previous owner.
91 Leggy turbo (Enos) Sec owner. 226000 mi and rolling
07 (JCW) Mini cooper s
91 leggy l fwd
94 Jeep cheroke sport (jep)
cj91legss
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Re: Installed cold air intake now having idle prob

Post by cj91legss »

Can you post a picture of what you have done?

If you need the plastic line the goes to both valve covers, I have an extra one sitting in my garage.
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James614
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Re: Installed cold air intake now having idle prob

Post by James614 »

I'm betting the key to at least get it to hold idle is to plumb that 3/4 line with the filter back into the intake. If the idle control valve is pulling unmetered air, it will essentially act as a "stall out the motor" valve. Then focus on fixing the other damaged lines.
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