> I have a truck with a 350 chevy in it, it has a 4bbl Qjet and it's a '79
> The carb has a man. choke
> When I start the thing it's fine, take the choke off as it warms up,
> driving
> and stoping at lights with it in gear and then going is fine. but if I
> stop
> and put it in Park or Netural, and let it idle for a few seconds, the
> second I
> step on the gas(even lightly) or put it into gear it stalls unless I
> pull the
> choke on full, this is all the time when it's cold and warm, if it's
> realy hot
> it just has to idle for a few seconds longer.  Does this sound like I
> need to
> rebuild the thing or some of the adjustemnts are off or does it even
> sound
> like a carb problem?  The thing that makes me thing like it it a carb
> problem
> it when it's stalling if I forget to pull the choke it makes a fairly loud
> sucking sound, I can just hear it over the engine with the driver window
> down.
>  and I don't have to hav ethe choke on for long, just a few seconds till
> I get
> rolling or it comes out of the low idle, but it is a pain.  Any ideas?
- Change the fuel filter.
 I don't care what anybody else says, but I've found the Q-jet sensitive to
dirty filters.
- Look down into the carb (use a mirror if your vehicle is prone to
backfiring) see how the fuel spray pattern is, if it tends to glob up,
you're due for the overhaul.
 --including full tear down and soaking. Don't just put in parts from the
rebuild kit and call it rebuilt.
-KISS goes a long way, so before doing anything costly snug all the screws
holding down the airhorn (9 screws). Small leaks can do lots of weird and
wonderfull things. Gut feeling tells me you have a small leak somewhere, but
since you operate properly (and idle I assume) under other conditions it
throws the vacuum theory partially out the door.
 Check all the linkages for free play.  Since your carb
appears to operate properly under most every other condition.  Also, check
for binding of the primary throttle plates.  You might need a new base
gasket. Do not overtighten the carb, snug it down and add a turn or two.
Have you got an idle stop solenoid on your carb? This critter could be going
out the door. Or, the wire feeding it 12v is jogged in some way by some
linkage.
Quick test, disable the idle stop solenoid, turn in the idle screw to set
your idle speed. (I go for about 750rpm, anything less and my engine will
start to stumble if its not fully warmed up.) Do your driving test and see
what happens.
Thats all that pops to mind, but try the above, and something my pop to mind
in the mean time. 
Alex.
 | AmiQWK 2.7 - S/N 0261 |
... Never trust a shop teacher that has less fingers than you do.
--- OLMS 2.60p.a1+ [EPMAP55A]
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