So after the long journey of finding all the parts I needed for my qjet I finally got it back on the car today. My idle in open loop is set at ~750RPM. Runs fine in open loop, but once it goes into closed loop it dies every time unless I give it gas, and even then I can watch the idle bounce up and down a few hundred RPM. Maybe the mixture control solenoid???

All adjustment screws are currently set at 4 turns in from seated. I am trying to get it to run consistently enough to run to the parts store and buy a dwell meter and carb tool since my other vehicle is in the shop til god knows when. The only real issue I can think of is the MCS adjustment screw hole where the brass piece goes through the air horn was f'ed up at some point in time and the only way I could adjust it is to pull the carb back off and drill the hole out bigger so you can actually turn the damn thing...

Also can someone hook me up with a picture/diagram/whatever of the choke assembly? I think I may have put something on wrong on that side. The choke works fine but there is a small silver piece about 2" long with notches cut in it and a hole in the middle that I don't think I put in the right spot... the service manual isn't very descriptive when it comes to putting the choke system back together

 

The q-jet sticky in the top section of this forum has all of the parts and adjustment details. Not all of the parts shown will be on your carb.

 

Fixed the choke assembly and got a multimeter with dwell and rpm settings.

Where do I check dwell? Is it that green plug hanging out near the AC fan box???

What's really pissing me off now is with all my screws set 4 turns from seated I have good idle but as soon as I start to drive it bogs out (and dies half the time). I unplugged the MCC and TPS sensors and I couldn't even back out of the driveway before it died. What am I doing wrong?

 

Insert a thin rod into the opening next to the IAB and ensure the MCS hat clicks up and down and travels only 1/8". Inspect your IAB for good seals.

Set your ignition timing to 0-4 degrees advanced with the four wire connector disconnected. Reconnect and observe that the timing is near 20 or so at idle and increases with throttle.

Set your TPS to near 0.40 volts at idle. Ignition in 'run', car does not need to be running. You may need to backprobe the B and C connector (middle/bottom) at the pigtail.

Connect the dwell meter to the green lead. With the engine warm see if you can get the dwell to start responding to changes in the IAB setting. Once the dwell starts varying slightly at idle it'll be in closed loop and you can adjust the IAB to get it to waver near 50%.

If no response, set your idle mixture screws to 2 1/2 turns out and the IAB to 2 1/2 turns out. Open the IAB a quarter turn at a time until the dwell responds. If no luck start over at 3 turns out on the idle mixture screws. Repeat until you are at, or near, 50% on the dwell and everything is close to 4 turns out.

A stock system should work somewhere near 3-4 turns out on everything.

 

Some carb checks before you start:

Make sure the secondaries are not hanging open at idle.

Make sure the primaries are not hanging off of the curb idle set screw with the choke off.

Plug every vacuum port on the carb and manifold with a cap. Get closed loop and good dwell, then reconnect each one. Observe for any change in dwell that may indicate a vacuum leak.

If your ignition system isn't new, replace your plugs, wires, cap and rotor.

Report back.

 

Thanks naf.

Your qjet rebuild post and the factory service manual helped me out a ton- this is the first carb rebuild I've ever done and I'm determined not to let it get the best of me.

I will try what you suggested and post back in a few days. I did a tuneup on the car right after I bought it last June but with as rich as it was running before the rebuild I should probably pull my plugs and see how nasty they are.