Running very rough when put into 'drive'
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Running very rough when put into 'drive'
I have a 1969 F100 2x4 with a 360 (Edelbrock intake, Holly 4BBL, Pertronix points eliminator kit) auto trans and power brakes and steering with a/c.
Yesterday I was puling out of a store that had a good dip in the exit before you hit level road again and once i hit the dip the truck died. I pulled it over and it started right up as usual. When I put it into 'drive' it ran VERY rough. I changed the coil and the pertronix kit and no better. I have also recently changed almost all of my ignition and electrical components recently.
I believe I have a vacuum leak somewhere but am not sure where. I recently replaced all the vacuum lines ran off of the carb as well. Where should I look?
It idles normal in park and neutral but runs very rough (and with no power, and I have to keep my foot half way in it to keep it from dying) when it is in drive or reverse. Any help would be greatly appreciated! This is my daily driver so I would love to get it on the road asap. Thanks y'all!
-Tyler
Yesterday I was puling out of a store that had a good dip in the exit before you hit level road again and once i hit the dip the truck died. I pulled it over and it started right up as usual. When I put it into 'drive' it ran VERY rough. I changed the coil and the pertronix kit and no better. I have also recently changed almost all of my ignition and electrical components recently.
I believe I have a vacuum leak somewhere but am not sure where. I recently replaced all the vacuum lines ran off of the carb as well. Where should I look?
It idles normal in park and neutral but runs very rough (and with no power, and I have to keep my foot half way in it to keep it from dying) when it is in drive or reverse. Any help would be greatly appreciated! This is my daily driver so I would love to get it on the road asap. Thanks y'all!
-Tyler
Lead Driver
Joined: Apr 2011
Posts: 6,399
Likes: 40
From: El Dorado, Arkansas
I have a 1969 F100 2x4 with a 360 (Edelbrock intake, Holly 4BBL, Pertronix points eliminator kit) auto trans and power brakes and steering with a/c.
Yesterday I was puling out of a store that had a good dip in the exit before you hit level road again and once i hit the dip the truck died. I pulled it over and it started right up as usual. When I put it into 'drive' it ran VERY rough. I changed the coil and the pertronix kit and no better. I have also recently changed almost all of my ignition and electrical components recently.
I believe I have a vacuum leak somewhere but am not sure where. I recently replaced all the vacuum lines ran off of the carb as well. Where should I look?
It idles normal in park and neutral but runs very rough (and with no power, and I have to keep my foot half way in it to keep it from dying) when it is in drive or reverse. Any help would be greatly appreciated! This is my daily driver so I would love to get it on the road asap. Thanks y'all!
-Tyler
Yesterday I was puling out of a store that had a good dip in the exit before you hit level road again and once i hit the dip the truck died. I pulled it over and it started right up as usual. When I put it into 'drive' it ran VERY rough. I changed the coil and the pertronix kit and no better. I have also recently changed almost all of my ignition and electrical components recently.
I believe I have a vacuum leak somewhere but am not sure where. I recently replaced all the vacuum lines ran off of the carb as well. Where should I look?
It idles normal in park and neutral but runs very rough (and with no power, and I have to keep my foot half way in it to keep it from dying) when it is in drive or reverse. Any help would be greatly appreciated! This is my daily driver so I would love to get it on the road asap. Thanks y'all!
-Tyler
The other end of the transmission vacuum line connects to the intake. If the jolt was hard enough, maybe it knocked the line loose from the modulator (?) --just a guess.
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I checked out the vacuum line and fitting off of the trans and it seemed fine; not loose or anything.
I'm most curious as to which vacuum lines engage when it gets shifted to drive? This would help narrow down my options to focus on.
Thank you for all of your help.
-Tyler
I'm most curious as to which vacuum lines engage when it gets shifted to drive? This would help narrow down my options to focus on.
Thank you for all of your help.
-Tyler
Tuned
Joined: Apr 2011
Posts: 298
Likes: 4
From: Highland CA
It sounds like the choke is not opening or stuck,this is the symptom that happens to me wen I forget to pull out my manual choke,
TASBOJ............................
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Cargo Master
Joined: Oct 2011
Posts: 2,254
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From: Kenner,La.
running rough
Try this, Have someone hold the brakes and put it in gear, try pulling one plug wire at a time to see if it is a dead cylinder. Also remove and plug all vacuum ports to be sure there are no leaks.
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Lead Driver
Joined: Aug 2003
Posts: 7,592
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From: **** hole San Jose ca.
Have you checked the dizzy vacuum advance for a leaking diaphragm.
Ya never know when one will fail. May be a can of quick start and spray it all around the carb base & vacuum lines. Recheck your timing could be timing jumped from loose timing chain from the dip in the road you hit.
orich
Ya never know when one will fail. May be a can of quick start and spray it all around the carb base & vacuum lines. Recheck your timing could be timing jumped from loose timing chain from the dip in the road you hit.
orich
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Whoops read the diagram backwards. The other 4 plugs are the ones covered with oil.
I changed them all out and it certainly liked that more but it still sounds like its missing a cylinder. My wires are new as is my coil, cap, and rotor.
Any thoughts?
I changed them all out and it certainly liked that more but it still sounds like its missing a cylinder. My wires are new as is my coil, cap, and rotor.
Any thoughts?
Lead Driver
Joined: Jul 2011
Posts: 8,679
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From: On the Edge of the Desert
Valve springs! Haha
No probably not. You say it's running bad only when it's in gear? Do you have a tachometer and a vacuum gauge? With those two instruments you can solve a lot of problems. I'm also leaning towards the vacuum leak possibility.
No probably not. You say it's running bad only when it's in gear? Do you have a tachometer and a vacuum gauge? With those two instruments you can solve a lot of problems. I'm also leaning towards the vacuum leak possibility.
Fleet Mechanic
Joined: May 2006
Posts: 1,571
Likes: 75
From: Wichita, KS
Does it idle high when in neutral? I have a vacuum port on my chevy pickup that just has a rubber cap over it. When the cap came off it idled much higher in neutral and was very rough running to the point of dying when in gear. I discovered this pulling into my parking lot at work. Barely made it off the street. Plugged the vacuum port and was good to go. Sounds almost entirely like what you've described.