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1977 Q-Jet Not preforming correctly

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Old 09-01-2015, 09:29 PM
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doctorgene
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Default 1977 Q-Jet Not preforming correctly

Gentleman, I have to feather my gas pedal at low speeds to make it run. No problem on the open Hwy. &/Or with high speeds. This was rebuilt a couple of years ago, & has run just fine for the last two years. Do I just need a new accelerator pump??? Or should I look at another rebuild. I tried gas treatment, No Avail. Thanks Gene
Old 09-01-2015, 10:13 PM
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OMF
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Sounds like your Qjet is another victim of ethonol in the gas. probably needs a new accelerator pump.....the viton kind.
Old 09-01-2015, 10:13 PM
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TimAT
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Check for vacuum leaks- playing footsie makes me think a vacuum hose split.
Old 09-02-2015, 12:39 AM
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Originally Posted by doctorgene
Gentleman, I have to feather my gas pedal at low speeds to make it run. No problem on the open Hwy. &/Or with high speeds. This was rebuilt a couple of years ago, & has run just fine for the last two years. Do I just need a new accelerator pump??? Or should I look at another rebuild. I tried gas treatment, No Avail. Thanks Gene

Check your fuel pressure by taping a pressure gauge to your windshield and observing the pressure while its acting up. If it shows a continuous 5 psi all the time at least you've eliminated the pump.
Old 09-02-2015, 12:27 PM
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Originally Posted by sstocker31
Sounds like your Qjet is another victim of ethonol in the gas. probably needs a new accelerator pump.....the viton kind.
Old 09-02-2015, 08:30 PM
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Strokemyaxe
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I'm no carb guru by any means. Lars rebuilt mine. But, Id start by checking for leaks. Mine was actually the base of the carb. Just needed to be tightened up. Next, I would see if the idle mixture screws could be adjusted to correct it. If it wasn't rebuilt with an ethanol friendly float, you could indeed need to open back up. Do you have an inline filter before the carb? If not, check your filter at the fuel inlet nut to see if you have any debris.

Just offering a logical troubleshooting suggestion..good luck to ya.
Old 09-02-2015, 09:17 PM
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7t9l82
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Before you waste time and money check your accelerator pump shot make sure you have a good solid stream out of the squirter.I'd bet the pump diaphragm is shot. Get one from Lars or Cliff Ruggles. It matters.
Old 10-02-2015, 02:16 PM
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doctorgene
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Hey to all of you guys, I ended up having a combo of things, The pump was bad, two years old, I found Vacuum leaks at the plugged off outlets, of the carb, & at the capped off Cruise control, & I pulled the distrub up 1/2 ", I only have driven this car 3 K miles since complete rebuild. The rubber caps were all ate up. I did remove the Carb & blew out all of it while it was apart. Electric fuel pump was @ 7 pounds. THANKS to all of you, I Appreciate all the help. Gene
Old 10-02-2015, 02:41 PM
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gungatim
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I have had that happen with cheap rubber caps as well. sometimes they rot out in a year. not sure what the story is, but I ended up using some factory vacuum line from a junk yard to make plugs on another project. The parts store caps were just plain junk...glad you gott'er fixed.
Old 10-03-2015, 09:24 AM
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Big2Bird
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Originally Posted by doctorgene
Hey to all of you guys, I ended up having a combo of things, The pump was bad, two years old, I found Vacuum leaks at the plugged off outlets, of the carb, & at the capped off Cruise control, & I pulled the distrub up 1/2 ", I only have driven this car 3 K miles since complete rebuild. The rubber caps were all ate up. I did remove the Carb & blew out all of it while it was apart. Electric fuel pump was @ 7 pounds. THANKS to all of you, I Appreciate all the help. Gene
Get the vinyl vacuum caps. They last a long time.

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