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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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| | | | Joined: Jun 2003 Posts: 565 'Bolter | | 'Bolter Joined: Jun 2003 Posts: 565 |
"Do not walk behind me, for I may not lead. Do not walk ahead of me, for I may not follow. Do not walk beside me either. Just leave me alone, you're starting to freak me out."
1957 GMC 150
| | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | | | | | | Joined: Feb 2006 Posts: 549 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 549 | did you figure it out yet? | | | | | Joined: Jun 2003 Posts: 565 'Bolter | | 'Bolter Joined: Jun 2003 Posts: 565 | Well I have a red face.I found the miss. I had ran the main power wire from the starter to the ign. switch in a poor location. It was being pinched between the valve cover and the firewall. The insulation was rubbed off and shorting out. Under heavy acceleration the engine torque gave it more clearence and it ran fine.
Thanks to all that gave me info.
"Do not walk behind me, for I may not lead. Do not walk ahead of me, for I may not follow. Do not walk beside me either. Just leave me alone, you're starting to freak me out."
1957 GMC 150
| | | | | Joined: Feb 2006 Posts: 549 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 549 | | | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | I missed a lot of stuff. the slight miss is still there. I'll find it eventually. | | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | Gazim,
Change the HEI module!.
Scott
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | OK Scott, I promise to do that this week. If you are wrong will I have any recourse? At least "I told you so"? 
Last edited by gazim; 08/09/2009 10:02 PM.
| | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | If that is not it, then it is in the cap, rotor, coil, or plugs. However the odds are it is the module.
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | I have already replaced all except the module. It just bugs me that it will idle smooth till 1500 miss till 2800. go like heck above that. Module check on tuesday. I bet everyone is getting tired of reading about this.
Last edited by gazim; 08/10/2009 1:47 PM.
| | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | You loose Scott. new module and still a miss. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | More information...
Is the truck missing? Or stumbling like it is running out of fuel?
Is there any backfire through the carb (like a cough)? Or is it backfiring through the exhaust?
What is the compression on the cylinders?
What carb are you running? Is it a Quadrajet? If it is a Quad, have the shafts been rebushed?
Tell us all what you have verified thus far. | | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | Builder, It is a slight miss or stumble at low rpm(not idle) No backfire (well maybe when I fumbled with the timing)
Running a fairly new edelbrock carb New double diaphram fuel pump, I havent checked the compression yet. Follow this thread back and you will find I have run out of things to check. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | Sometimes running lean on the low side can make a stumbling or "cough" through the carb at lower RPMs. | | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | The next step is to put it on a scope and watch each cylinder.
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Apr 2009 Posts: 60 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 60 | Could be yer blinker fluid is low | | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | It just might be, The indicator light doesn't work on left turns.Someone also sugested the muffler bearings. | | | | | Joined: Feb 2007 Posts: 10 New Guy | | New Guy Joined: Feb 2007 Posts: 10 | gazim, I have a Edelbrock carb on my FJ40, even with fuel filters a fine silt type junk accumulates in the carb after a wile. When it starts missing, I yank the carb, take the top off and hose it out with carb cleaner. Clears the miss right up. Might give that a try.
salvo
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