I bought an 86 T.A. rebuilder and the guy just put on a new rochester carb but messed with all the setting and I do not have a clue where to start to adjust it,but it runs like ....(bad)Any suggestions?The choke doesn't close when you turn on the key and hit the accel.and after it warms up the butterfly only open partial .It can be turned rich or lean but it only makes it better after it is warmed up.

 

The choke doesn't need power to close. It needs to be cold in order to close, however. If, when completely cold, before turning on the ignition, you open the throttle and it doesn't close, and after running for awhile it doesn't open, that sounds like a bad choke thermostat. Or, one that isn't properly installed so that it engages the choke mechanism tang.

The Haynes Rochester shop manual and Doug Roe Rochester book have a section on the computer command carb. I don't have it in front of me, don't recall off hand if it gives you pre-adjustment settings. However, having just rebuilt my carb a couple of months ago, I remember distinctly that the kit does include instructions with those settings, but you need a couple of adjustment tools to do it properly (a search of this forum should yield some candidates for you to consider). When I reinstalled my carb and got the engine running, I adjusted the idle speed slightly, and the idle air bleed a whole 1/8 of a turn. It's been running great since.

 

pontiacsteve,
If you have an AutoZone or AdvanceAuto nearby you should be able to find one of these manuals on their shelf. It's be best $15 you'll ever spend if you have a Rochester Carb.

Adjusting the carb normally takes a few special tools. However, as Five7 mentioned you may have something screwwwy in the choke which would require no special tools to verify and rectify. If I had a scanner I could send you the pages related to the choke. Unfortunately, I don't have one.

I'll try to type and post a short list of bullet points/check list items to help out. The parts stores are probably closed today.

Sincerely,

 

I will pick up one of those manuals tomorrow. This can be a very frustrating hobby when it is "learn as you go."On the other hand I enjoy the challenge,which is why I try to do all the work myself, which would not be possible without the help of a lot of knowledgeable people willing to take the time to help.Thanks for the input.

 

Thats true, but in my experience, thats the best way to learn alot of thing, especially stuff that involves trouble-shooting or tuning.

When I learned to tune my Qjet, and now my Holley, I just kinda winged it, tried stuff, trial and error... and now I bought a Holley manual, and it doesn't tell me anything I don't already know, LOL.

 

I got the Haynes manual, but I am pretty confused now. The choke works correctly, the car idles fast initially on cold start and when I tap the gas it backs off. The problem is when I put it in gear and touch the gas it revs to 2k rpm and won't idle down. It is a Q-jet but does not have a model # anywhere, it is however, electronic. Any thoughts?

 

my WAG is that there is no dashpot, so you may have an adjustment issue with the Q-Jet. There may also be some throttle shaft binding, or poor adjustment of the secondary throttles.