Author Topic: Vile need your Help!  (Read 2943 times)

Offline joesgarage71

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Vile need your Help!
« on: August 19, 2007, 05:25:48 PM »
 I'm still having problems with the 86,She lays down when under a load (going uphill) most of the time. Some time it runs good. I had the factory carb rebuilt and it still done it, I replaced the carb with a 78 Q-Jet. Still lays down.
 I had the modual tested by two different stores,I replaced the plugs, wires, dist cap, rotor, I set the timing. The vacuum advance is working good. It has good fuel pressure. I doesn't pop or cough it just slows down no matter how much gas you give it or what gear you change to.
 I'm starting to think the computer is bad.




 1986 C-10 305-4 bbl/Th350 98K miles
 Steve
« Last Edit: August 19, 2007, 05:30:03 PM by joesgarage71 »
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline VileZambonie

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Re: Vile need your Help!
« Reply #1 on: August 19, 2007, 08:55:22 PM »
Put a vacuum gauge on it and run the hose up through the cowl. Tape it right ot your windshield and take it for a rip. Does it do it when it's cold or just when it's warmed up? What did you set the timing to? Did you check the centrifugal advance?
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline joesgarage71

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Re: Vile need your Help!
« Reply #2 on: August 20, 2007, 07:53:42 PM »
 It does it when its warm. the timing is set to spec. It has 16 in of vacuum at idle. The mech advance weights are free and have full movement. What am I looking for with the Vacuum gauge?

Steve
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline VileZambonie

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Re: Vile need your Help!
« Reply #3 on: August 20, 2007, 09:40:00 PM »
You should have better than 16inHG at idle. Try to advance the timing and see what it does. Are you sure you don't have a kinkied fuel line somewhere? With the vacuum gauge that can help you pinpoint several problems....from timing to restricted exhaust. Try advancing the timing first.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline DnStClr

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Re: Vile need your Help!
« Reply #4 on: August 22, 2007, 09:49:10 AM »
Not to butt in, but the restricted exhaust idea might just be what's going on. Plugged cat maybe?
Don
87 Chevy Silverado

Offline Lt.Del

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Re: Vile need your Help!
« Reply #5 on: August 22, 2007, 11:35:27 AM »
or sticking flow valve in the RH exhaust manifold, if it is stock. 

Offline rdhack

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Re: Vile need your Help!
« Reply #6 on: August 22, 2007, 12:37:27 PM »
I would bet my money on a plugged exhaust system.

Offline joesgarage71

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Re: Vile need your Help!
« Reply #7 on: August 25, 2007, 02:47:47 AM »
 It doesn't do it all the time, I removed the cat and the valve is open.That was the first thing I thought of. I have to work today but will do the vaccuum gauge later today.
 Steve
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline DnStClr

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Re: Vile need your Help!
« Reply #8 on: August 25, 2007, 10:04:35 PM »
I hope you find a vacuum leak. If that's not it, the trans might be the next place to be suspected. 
Don
87 Chevy Silverado