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Discussion Starter · #1 ·
lately my car starts and then stops and then runs fine after I start it again. Its a standard old set up with the quadrajet and rod and spring choke on the manifold.When I tried to adjust the choke it started then wouldnt start until it sat for afew hours and then I had to crank it for awhile before it turned over. This is the first time that has happened. I checked the hoses and noticed that on fast idle cam, when I pull off the distributer advance vacuum hose it slows down the engine, but on normal idle cam on the other side of the carb there is no difference in egine speed when I pull off that vacuum hose . Obviously I don't really know a lot about carb/advance hose relationship to the engine vacuum. Ive rebuilt a few different carbs fine over the years, but never ran into this problem or situation. Does this ring a bell with anyone who knows about this stuff?
 

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Have a helper start the car while you watch the choke plate (air cleaner off). If the engine is cold, a light tap of the throttle should cause the choke to snap shut (not completely shut). Then as you crank the car and the car starts to run, the choke plates should open a bit. A vacuum servo on the carberator is what opens the choke -- it's called a choke pull-off actuator. I suspect you have a hole in the diapham for the choke pull off and it isn't working correctly.
 

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Discussion Starter · #3 ·
Thanks, let me explain about the original probelm. After sitting and cold, the car will start immediately, run about 5
seconds, and die. It doesn't matter if it has set overnight or for two
weeks. On the second start after stopping, it fires up but needs a couple light pumps on the gas pedal, and it will after about 4 seconds even out on the normal higher idle running cam fairly well. After 2 minutes its fine to drive. When cold, the choke plate closes all the way, then opens a tad when it starts. Maybe that adjustment is wrong? or the fast idle cam adjustment? I dont know, thats what I adjusted this morning and it ran rough and died and then wouldnt start till let it sit a few hours then it did eventually start after cranking a few times. It seemed to run fine after that but I havent started it cold again. I will wait till tomorrow. I adjusted the settings back to about where they were. Ive heard a lot of questions about quadrajets that start fine, die , then start again, but not a lot of answers. I have seen message boards about this problem but the only advice Ive seen is try to adjust the pull off and the fast idle cam. I'll try again tomorrow. any more advice appreciated.
 

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Discussion Starter · #4 ·
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Join Date: Feb 2001
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David has it right about the adjustments. He also has it right about some Qjets will die after about ten sec no matter what you do.




I found that in a search on the topic here. The thing is, my car used to be fine and start and run normally. Only lately has this nightmare developed. I will keep playing around and try to solve this or get another quad if I cant figure it out.
 

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After it dies and will not re-start, try manually holding the choke open while cranking to see if it will start. If it starts. it is flooded. And, I expect Dave is correct with the choke pull-off. or other choke adjustments needing cleaning or correction. To test the pull off remove the vacuum hose to it, depress the plunger and then put a finger over the end of the tube to block it off. The plunger should release just slightly and hold, then release your finger off the tube, the plunger should slowly move out the rest of it's travel. If not then replace the choke pull off and adjust the linkages.


TTFN
Mat
 

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Discussion Starter · #6 ·
Ive been tinkering all morning. The carb seems to like to have the choke open more than the diagram/stat sheet says. I adjusted the pull off to let more air in after it re started while i held the choke plate open while cold on the second start or the one after it started and ran for 5 seconds then died. I suppose this means its getting gas from somewhere it shouldn't. I think i'll take the carb off , fill the bowls aand let it sit with gas in it over the weekend and see if any drips out.
 
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