Author Topic: 350 problems  (Read 15494 times)

Offline greenmonster

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350 problems
« on: February 17, 2010, 06:59:34 pm »
My truck isn't running right.It idles a little rough and it shakes when I give it the gas but it cruises fine until I get to 60-65 mph then it start shaking.
I put new plugs,wires,cap,rotor,vac advance,fuel pump,fuel filter and fuel lines.I have a 1 1\2 old edelbrock carb.I tore it down and every thing looked fine.
I,m lost ,any help or ideas would be great.

Offline VileZambonie

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Re: 350 problems
« Reply #1 on: February 17, 2010, 07:09:14 pm »
Sounds like an ignition miss. Pinpoint which cylinder is causing the missfire.
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Offline greenmonster

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Re: 350 problems
« Reply #2 on: February 17, 2010, 07:11:42 pm »
How do I do that.

Offline Irish_Alley

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Re: 350 problems
« Reply #3 on: February 19, 2010, 12:08:29 pm »
pull a plug wire at idle if it doesn't change its you bad plug or wire. if you pull it and it gets worse its not your problem. did you change everything before the problem or after?
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Offline greenmonster

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Re: 350 problems
« Reply #4 on: February 19, 2010, 01:35:21 pm »
I changed everything after the problem.I changed the coil too.

Offline Irish_Alley

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Re: 350 problems
« Reply #5 on: February 19, 2010, 04:02:56 pm »
what year is this
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline greenmonster

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Re: 350 problems
« Reply #6 on: February 19, 2010, 04:43:38 pm »
75 with a 350

Offline VileZambonie

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Re: 350 problems
« Reply #7 on: February 19, 2010, 06:16:35 pm »
pinpoint the cylinder that is causing the problem. Set the idle at 1,000 rpm. Short one cylinder at a time and measure the rpm drop. If each cylinder dropped it to 800 rpm for example except for say #3 cylinder, then investigate #3 cylinder. Are you sure you didn't cross #5 and #7 spark plug wires?
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Offline greenmonster

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Re: 350 problems
« Reply #8 on: February 19, 2010, 06:31:21 pm »
Ok I'll try that.The pluges aren't crossed because it was running fine,then I didn't drive it for 3-4 days and when I drove it the problems started.That was before I put all the parts on it.

Offline greenmonster

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Re: 350 problems
« Reply #9 on: March 02, 2010, 03:42:36 pm »
I still can't figure out what cylinder is misfiring.I did a compression test just because and it was 145-155 psi,so I think that is ok.Could the module cause this or maybe the pickup.How do I test those.

Offline VileZambonie

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Re: 350 problems
« Reply #10 on: March 02, 2010, 03:44:53 pm »
What carburetor are you running?
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Offline greenmonster

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Re: 350 problems
« Reply #11 on: March 02, 2010, 03:47:21 pm »
Edelbrock 1406 about 1 1\2 years old.

Offline greenmonster

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Re: 350 problems
« Reply #12 on: March 02, 2010, 03:53:08 pm »
I put a vacuum gauge on it today and it was moving about 2 in real fast. Is that normal.

Offline VileZambonie

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Re: 350 problems
« Reply #13 on: March 02, 2010, 03:56:38 pm »
Clarify what you are saying... ???

Take the air horn off of the carb. Clean out the inlet and remove the sock filters. Check inside the bowl area for crap. Check your float level and float drop. Make sure the needle and seat are working without sticking.
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              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

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

Offline greenmonster

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Re: 350 problems
« Reply #14 on: March 02, 2010, 03:59:57 pm »
If you are talking about the vacuum reading,it was moving 2in/hg back and forth fast.