Fuel Cut Off Help w/ pictures

Spike Strip

Oh, the Pain!
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Saw your PM --

Vac leaks? Vac hoses correctly routed. Any borken cracked hoses? Big hose to brake booster?

Check the A/C idle up (disconnect the vac. hose and block it and see what happens.... In my above pic, it's the hose to the diaphram just under the green connector).

Do a search for this issue, there's gotta be other suggestions out there...
 
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To revive a long dead thread...let me just say that thanks to this post I finally tracked down the stumble/flat spot/crappy performance I've been chasing and tinkering with for months.

When I did my de-smog I apparently misidentified the fuel decel vacuum switch on the drivers' fender well and removed it completely, not knowing what it was. I had the hose coming from the decel port on the carb going to the spaghetti manifold but simply capped the other end thinking as long as it wasn't creating a vacuum leak it should probably be fine.

Come to find out the computer was activating the fuel cutoff solenoid the whole time I was driving around. It's amazing how crappy this thing can run when the fuel gets pinched at 1800 rpm. Couldn't figure out why it was so lean....go figure.

Many, many, many thanks -I've lost so much hair over this and had at one time or another questioned every component on my truck to the point that I was going nuts.

$1.97 for a pack of ring connectors and about 3 mins in the Home Depot parking lot...I've literally found a new truck. It runs like it's new.

Big take away #1) If you don't know what it is or what it does - don't mess with it.
#2) The answer to most issues is somewhere on this forum. Took me months of reading other people's symptoms and troubleshooting to find it, but it was here.

Loving life right now.
 
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To revive a long dead thread...let me just say that thanks to this post I finally tracked down the stumble/flat spot/crappy performance I've been chasing and tinkering with for months.

When I did my de-smog I apparently misidentified the fuel decel vacuum switch on the drivers' fender well and removed it completely, not knowing what it was. I had the hose coming from the decel port on the carb going to the spaghetti manifold but simply capped the other end thinking as long as it wasn't creating a vacuum leak it should probably be fine.

Come to find out the computer was activating the fuel cutoff solenoid the whole time I was driving around. It's amazing how crappy this thing can run when the fuel gets pinched at 1800 rpm. Couldn't figure out why it was so lean....go figure.

Many, many, many thanks -I've lost so much hair over this and had at one time or another questioned every component on my truck to the point that I was going nuts.

$1.97 for a pack of ring connectors and about 3 mins in the Home Depot parking lot...I've literally found a new truck. It runs like it's new.

Big take away #1) If you don't know what it is or what it does - don't mess with it.
#2) The answer to most issues is somewhere on this forum. Took me months of reading other people's symptoms and troubleshooting to find it, but it was here.

Loving life right now.

Jey Jesper - thanks for the follow up. What exactly did you do to fix it? Tahnks!
 
Joined
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Jey Jesper - thanks for the follow up. What exactly did you do to fix it? Tahnks!
I grounded the white wire to the carb body using a ring connector as seen in Spike Strip's post (pg 1, post #12)...super easy and made a world of difference for me. HTH
 

Comet

Knower of little, master of less.
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My limited understanding is if you hear the click of the solenoid, you don't need to ground the white/black stripe wire. The green wire gets hooked up to the carb plug. I believe, if I have read correctly, the green wire mod only eliminates the electronics from the equation. Trollhole carb is the same as what I ordered from city racer and I only plugged in the green wire.
 

NeverGiveUpYota

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My limited understanding is if you hear the click of the solenoid, you don't need to ground the white/black stripe wire. The green wire gets hooked up to the carb plug. I believe, if I have read correctly, the green wire mod only eliminates the electronics from the equation. Trollhole carb is the same as what I ordered from city racer and I only plugged in the green wire.
Solenoid can still be faulty even w/ an audible click. At minimum have you pulled it off the carb and check the tiny little o-ring (in the pix below where my thumb is pointing is where it would be)... ? You can find a replacement at an Ace. They have a great assortment. Mine when looked w/ a magnifying glass was dry rotted. You'll need a 12mm (if memory serves right) wrench and you'll need to remove the bolt that pivots the ACC to be able to remove the solenoid from the carb.

image.jpg
 

Spike Strip

Oh, the Pain!
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@NeverGiveUpYota you rock! I just installed the fuel cutoff directly to the fuel filter vacuum. Is that right?
My limited understanding is if you hear the click of the solenoid, you don't need to ground the white/black stripe wire. The green wire gets hooked up to the carb plug. I believe, if I have read correctly, the green wire mod only eliminates the electronics from the equation. Trollhole carb is the same as what I ordered from city racer and I only plugged in the green wire.
If you have a one-wire carb (non-stock, non-usa carb), then your decel-fuel-cut system is not going to work, period, as it controlled through negative ground.

 

Comet

Knower of little, master of less.
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Good info, not from me! Please disregard my above statements regarding the solenoid and the fuel cut off. Thanks guys and gal for keeping me on the straight and narrow. Carry on.
 
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