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Old 05-08-2008, 05:57 PM   #1
Ole Blue 68
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Truck's Not Running Right

I drove the truck to work this morning and it wasn't running right. This is the first time I've ever had this problem so any input you can give would be appreciated. It ran fine at lower RPM's but when I started getting up to @40mph or higher it would start to bog a little and then I would hear a little spit out of the exhaust (sounded like the right bank), almost like it was missing. I was about to pull over and check it out when it started to running fine. When I got to work I didn't notice anything out of place.

I was thinking possible vacuum leak but then I ruled that out since it seems to have corrected itself. I thought may be an exhaust leak but I don't think that would cause it to bog. My other theories would be either bad gas in the line or an ignition problem (cap, wire or a plug).

What do you all think?
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Old 05-08-2008, 06:02 PM   #2
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Re: Truck's Not Running Right

Ignition. I had this same problem after I got my engine pressure washed. I ended up swapping the points dizzy for an HEI, which solved the problem...
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Old 05-08-2008, 06:07 PM   #3
Ole Blue 68
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Re: Truck's Not Running Right

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Ignition. I had this same problem after I got my engine pressure washed. I ended up swapping the points dizzy for an HEI, which solved the problem...
Yeah, it reminded me of a points problem too but I'm running an HEI now. Maybe the hold down clamp has come loose....I'll have to check it.
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Old 05-08-2008, 06:17 PM   #4
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Re: Truck's Not Running Right

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Originally Posted by Ole Blue 68 View Post
Yeah, it reminded me of a points problem too but I'm running an HEI now. Maybe the hold down clamp has come loose....I'll have to check it.
If thats not it, you might have a vacuum line sucking closed at higher pressure also. Might check for a weak hose somewhere.
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Old 05-08-2008, 06:23 PM   #5
Ole Blue 68
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Re: Truck's Not Running Right

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If thats not it, you might have a vacuum line sucking closed at higher pressure also. Might check for a weak hose somewhere.
I'll check the hoses too. Thanks!
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Old 05-08-2008, 06:55 PM   #6
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Re: Truck's Not Running Right

check your harness over the drivers inner fender - mine did it, then ran good then, THEN filled the cab with smoke. melted the entire in cab harness - it was pinched in behind where the inner and outter meet. Might not be it but, it's a quick easy thing to check either way.
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Old 05-08-2008, 07:20 PM   #7
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Re: Truck's Not Running Right

Thanks Luvlegs, I'll check that too.

I just took it out for a quick run here at work and it's still doing it. I checked all the vacuum lines and they all seemed fine. Just the way it runs and sounds, I'm thinking it's gotta be ignition.
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Old 05-08-2008, 11:39 PM   #8
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Re: Truck's Not Running Right

Check your plug wires on the dist. and check the cap, make sure it's secure and on straight. That same thing happened in my Jeep, one of the dist cap clamps managed to work it's was loose and the cap was lopsided. If' that's good, then get your timing light out when you get home.
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Old 05-09-2008, 03:03 AM   #9
Ole Blue 68
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Re: Truck's Not Running Right

It was the clamp for the distributor. I've got a billit clamp and it's stopped gripping against the dizzy no matter how much I tighten it.

Thanks to all for the advice!
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Old 05-09-2008, 03:21 AM   #10
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Re: Truck's Not Running Right

What did you do to fix it? When you do fix it, remember to check your timing, just to be safe.
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Old 05-09-2008, 06:40 AM   #11
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Re: Truck's Not Running Right

Haven't fixed it yet. I'm gonna see if I can find a way to create some grip between the clamp and the dizzy; maybe grind the inside of the clamp a little or something. If that doesn't work then I'll have to try a different clamp.
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