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High idle, off idle bog and slow revving

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Old 12-27-2014, 12:10 PM
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
High idle, off idle bog and slow revving

First off, this is my 85 3.8 2 barrel regal I purchased this past summer. Even though I plan on dropping a ported head/cam 455 in it when it's done I'd still like to get this motor to run right so I can move/drive the car so I can take my time getting everything on the 455 perfect before I do the swap.

A little history on this car. It was a craigslist "barn find." The car was wrecked in early 90s and hadn't been registered since 93. It had sat inside, heated storage since. It hadn't been touched so needless to say it was covered in a layer of dirt. The car was complete except for the carb. Purchased a carb that was pretty much a core. Got the motor to bust loose and she fired up. Wish I had that on video. It was a sight to see and hear lol!

I've found numerous small problems with the car. None have actually fixed it. It will start just fine, although it seems to turn over slow. I'm sure that's the starter causing that. Fires up and immediately goes into high idle, 1800-2000 rpm. No matter how long I let it run it usually stays that way. I've busted the cat out, replaced wires, replaced plugs, replaced most of the vacuum hoses that matter, plugged off the rest. Smog is gone and capped off. Fresh gas, new filter. Replaced the carb with a reman from the junkyard off a car that drove in and put a new filter in that also. Sprayed wd40 everywhere and saw no bubbles or heard no change in idle. EGR isn't stuck. Even blocked off the line to that and plugged off the port on the egr, nothing. Replaced accelerator pump. No change. Carb ports are clean.

Found two broken wires. One was the wire going to the 02 sensor. I repaired that. Also had a bad wire going to the knock sensor. I repaired that also. The motor pulls 16 inches of vacuum. Modulator valve on the trans is fine. 5-6 lbs of fuel pressure. Doesn't change when the motor bogs either. Doesn't die when put into gear but it will at random and sometimes is a pita to start again.

I'm freakin LOST! Could this be ignition related? 02 maybe? I dont' have a scanner. I do have a dwell meter though but don't know what good it will be since the car won't idle down. Any suggestions would be much appreciated. I know, it's not the iroc I wanted to buy but hoping to sell it someday so I can get the convertible I always wanted.
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Old 12-27-2014, 12:12 PM
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
Re: High idle, off idle bog and slow revving

Yes I could post this on a regal or gbody forum but most of those guys rip all the emissions crap out when they swap they sbc's in every damn thing. I know there's quite a few guys here that like to keep their cars all original so I figured this would be the best place.
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Old 12-28-2014, 04:15 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: High idle, off idle bog and slow revving

I hear ya. But, 3rd gens didn't come with 3.8s, 3rd gens didn't come with 2 bbl carbs (at least not the same type as 3.8s had). So it's impossible to bend this as being "3rd gen related".

Sorry.

(Maybe someone would be willing to PM you with some advise)
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