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Old 05-30-2007, 09:54 PM   #1
BJA69C10
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Not running perfect...need some help please

So, my truck has been running really rough lately. we thought it was a timing issue, so we sent the truck to be looked at. I just got her home today (after three months ) and it still isn't right. We had a brand new HEI distributor put in, with new coil, cap, rotor, plugs, wires, etc. But the truck still seems to be miss firing. heres the symptoms:

Runs fine at idle or when reved in nuetral

Makes a popping noise under acceleration, similar to a backfire, but almost seems like it's going to stall

sometimes it clears up as the rpms rise

and lastly...it seems to run perfect imediately after a left hand turn?

Maybe the truck was meant to be a circle track racer?? I'm thinking it could be carb problems or maybe some water in the fuel tank (stock location).

I do have an Edlebrock 4bl and intake that i could put on...

Sorry for the long post, I just want to figure this out so I can get her painted =]

Thanks for all of your help guys,

Brad
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Old 05-30-2007, 10:19 PM   #2
Bus Ted Knuckle
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Re: Not running perfect...need some help please

The popping on accel makes me think timing. Are you sure, and I mean stone cold positive that you don't have a couple plug wires switched?

Double and triple check your sparkie order.

THEN...

If you really thnk you got some water in your fuel, put some HEET in your tank and run it. It'll bind the water and let it pass through the engine.

Have you changed your fuel filter lately?

You got me on the left hand turn thing ...

Now what is the deal with a shop having your truck for three months and not fixing the problem?
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Old 05-30-2007, 10:46 PM   #3
woodrow59
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Re: Not running perfect...need some help please

Unless it's you're brother-in-laws shop or your dads shop take it somewhere else.

Left hand turn thing,,,,,,,maybe it puts more gas to the carb ????
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Old 05-31-2007, 12:31 AM   #4
oldiron
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Re: Not running perfect...need some help please

Check the shaft star wheel that breaks the field on the module. I had one that came loose on a new HEI. Had the same problems. It would retard on acceleration and advance on deceleration. Drove me nuts.
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Old 05-31-2007, 01:06 AM   #5
GREASEMONKEY72
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Re: Not running perfect...need some help please

the left hand turn thing is weird but maybe youre timming chain is bad, have you changed the initial timming at the balancer and see if theres a difference?
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Old 05-31-2007, 06:21 PM   #6
BJA69C10
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Re: Not running perfect...need some help please

Timing has been changed back and forth at the balancer...its at about 8* advanced right now

Plug wires are all in the correct order...

this really has me stumped, but im going to try a new fuel filter and some HEET or drygas this weekend, hopefully it works

Thanks guys,
Brad

Oldiron: it had the same problem with the stock distributor and a mallory electronic ignition kit, but worse...could the star wheel you mentioned still be a problem?
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Last edited by BJA69C10; 05-31-2007 at 06:23 PM.
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Old 05-31-2007, 07:51 PM   #7
cdowns
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Re: Not running perfect...need some help please

did your mechanic know he had to run a new12volt supply wire to convert to hei?? when it was converted to hei did they also gap the plugs for proper hei clearance?

i also suggest new fuel filter and checking under the passenger side to see if the rubber hose needs replacing also checking vaccume hose for cracking and dryrot(especially the one hooked to the tranny modulator if you have an auto tranny
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Old 05-31-2007, 08:12 PM   #8
GREASEMONKEY72
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Re: Not running perfect...need some help please

whats HEET or drygas?
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Old 05-31-2007, 08:32 PM   #9
Wreckless_71
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Re: Not running perfect...need some help please

I had the same problem... I changed the fuel filter, checked timing, etc. Finally I was checking the timing and saw a plug wire boot was split and sparking on my header... Got all new plugs and wires and seems to run great. If you have the eccel custom hi-temp do-it-yourself kit make sure you got the wires all the way into the boot. I felt like a huge moron after figuring that out! Basiclly check for fuel, spark, and air.
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