Hello all,
To start, I have an 84 trans am with a quadrajet carb. I had the carb running good but alot of staining on the housing and it kept flooding when starting hot.

first off, I noticed the choke pull off is keeping my secondaries from opening. The vacuum pulls it closed then wont release, not even after reving up the engine.

I also noticed that it's running lean with a light white smoke coming out the exhaust.

When I put the apt screw back in, I counted the same 3.75 turns from bottom but read some are 2.5 and others 3.5. What should it be set to and is this also the cause for the secondaries?

I dont have an opening for the apt, which means I will need to open it up again.

Thanks in advance.

 

Is this a manual or electronic QJet?
The secondary "pull-off" should take about 2 full seconds to completely release.
Pull the vacuum line while it's running and watch it release.
If it opened too quickly, you would get a huge bog.
If the 2 long screws at the rear of the airhorn were tightened too much, then the casting deforms toward that secondary air valve, and can even bind it closed.
Push the plate open with the engine off, and see if it is catching. Correct this problem with a file, or dremel. Have a vacuum cleaner running while doing this.

 

Thanks NoEmissions84TA,

I have a manual QJet.

The secondary air valves are fine, if I remove the vacuum, it takes about 2 seconds to close. also, if I keep it this way and punch the gas, the valves open. but if I keep it connected, it doesnt work.

how about the APT screw on the inside? what is the proper adjustment for this?

 

From what you described, it has to work. Unless there is something mechanically not letting the plate open. It will NOT be instantaneous.
Go up a long, gradual hill in high gear (try not to let the transmission kick down into a lower gear) and floor the gas. After a few seconds, you should hear that low growl roar of the secondaries opening.
Is your air filter somehow causing an interference?

Doug Roe's Quadrajet book says start at 2 turns out for APT.
http://www.73-87.com/7387garage/drivetrain/myqjet.htm