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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
 

dustybumpers

don't play well w others
Check the power brake booster vacuum line, maybe it got pulled out.
if that happened, check for a bad/broken motor mount
 
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

Its got me stumped,but what you described,sounds like an eccelerator pump.
Idles fine,but runs rough an lacks power,like starving of fuel.
 

Fellro

Moderator
Staff member
I'm with Charlie, make sure that vacuum line didn't get pulled or crack. That one was a source of aggravation for quite a while for me on my old 75. Had a collapsed hole on the underside where it was hard to spot. It likely idles a bit high, then loads up when put into gear.
 
I'll check those suggestions out. Yeah it's so odd how it runs well in park but bad in drive. I'll let y'all know how it turns out.

Any other ideas would be appreciated!

-Tyler
 

DNFXDLI

The Token Canadian
Staff member
Any chance the distributor slipped?....I have had that happen once.
 
I checked all of the vacuum lines running off the the carb and off the brake booster and off of the trans. No luck so far. Anybody know which vacuum lines engage when the trans is shifted to drive? Thank you all for your help.

-Tyler
 

DNFXDLI

The Token Canadian
Staff member
Can you go into more detail about the distributor slipping please?

Just simply the bolt can become loose and physically move the distributor....enough that it idles ok but once you get on the wick it runs like crap....it's just a thought.
 

dustybumpers

don't play well w others
Have you checked to see if the carb is bolted down tight?
might be loose, and when you hit the throttle, is raising up, and creating a huge vacuum leak, letting off the throttle settles down

Spray carb cleaner all over the intake, vacuum lines, carb base, anywhere there is vacuum at idle.
If the engine speed increases, you have found your vacuum leak

If you have no luck at idle, have someone hold the throttle down at 1/4 throttle, and spray carb cleaner in all the same places. if the engine races higher, you have found your leak
 
I just pulled my sparkplugs and the 4 closest to the firewall were all soaked in oil. I will replace all of my plugs and report back. I'm curious why it was just the rear ones (#'s 6,5,1 and 2)
 
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?
 

dustybumpers

don't play well w others
firing order correct?
 

Fellro

Moderator
Staff member
Ford numbers the cylinders different than any other, so be sure you are aware of that. It is like this:


Front of motor
5 1
6 2
7 3
8 4
Firewall

tecnovative_152.gif
 
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