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Old 04-11-2009, 05:38 PM   #1
CG
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Join Date: Feb 2002
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Still have that stutter problem

I dont know it this is electrical or mechanical or what so Ill toss it out here.

71 K20, stock 350, quadrajet, headers and Pertronix distributer and coil upgrade.

Driving around town, no problems at all, even when I get on it and wind it out it never misses.

Driving down the road 50 plus mph going along fine and then it sort of stutters or misses. I let off a sec and back up to speed no problems. Little further down the road, more stuttering.

I pulled the cap and rotor, they looked kinda corroded so I replaced them. Took her on a 20 mile run, no problems at all. I figured she was fixed. I seldom drive anywhere except my general area so no need to go above 40 mph. Next time I needed to do some freeway speed driving, I got about 3 miles from my house and its doing the miss thing again.

Today I put a new fuel filter in. No help. I pulled it into my garage with the door closed and lights out (no windows in my garage) and fired it up looking to see some sort of grounding or sparking problem...nothing.

It has the super thick aftermarket wires (Accel) so Im pretty sure those are fine. I would think if it had plug problems when I was getting on it some I would get the stuttering problems.

Im just taking a stab...Maybe I should get rid of the Pertronix dist and put a regular HEI in there. I do have a couple of extra ones floating around somewhere. Not to sure on the process of putting one in after having the Pertronix in there. Here is a link to the dist in case you havent heard of them...http://www.pertronix.com/prod/ig/ignitor/default.aspx

Open to any ideas. I dont like to have to ask my honey to use her Trailblazer to haul my trailer around...Thanks for any help.
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Old 04-11-2009, 06:12 PM   #2
68gmsee
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Re: Still have that stutter problem

If you've already checked your fuel delivery and the fuel pump delivers the required amount in so many seconds, then what you're considering is what I would do.

Try another distributor. I had a similar problem but it was on an older HEI I had gotten from the junkyard. I took it apart, replaced all of the components, cleanded and regrease the shaft, relubed the module, new pickup coil, made sure the vacuum advance was working, etc.. Problem solved.
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Old 04-11-2009, 09:51 PM   #3
CG
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Re: Still have that stutter problem

Now all I have to do is figure out where I put those HEI's LOL.
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Old 04-11-2009, 10:45 PM   #4
68gmsee
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Re: Still have that stutter problem

I saw this the other day posted by norwegianc10. I noticed this particular comment:

"If you have no engine knock under acceleration, but the car chugs or jerks at cruising speed (light throttle application), you are getting too much vacuum advance on top of the mechanical advance. You may need to change out the vacuum advance diaphragm with an adjustable unit available from aftermarket sources. Adjust these units so that you get the most vacuum advance possible without any chugging or jerking at cruise speed."
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Old 04-12-2009, 12:20 AM   #5
CG
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Re: Still have that stutter problem

Hmm, this is really interesting. Its sounds exactly like whats happening to my truck.
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Old 04-12-2009, 01:20 AM   #6
oldiron
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Re: Still have that stutter problem

Quote:
Originally Posted by CG View Post
Now all I have to do is figure out where I put those HEI's LOL.
Psst! Right next to my front driveline!!!

Sorry I couldn't resist.
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