84 12a carb problem

[ITS5GB]

I picked up an 84 gsl thinking I would try to build an IT7 car. Forget it! Way too much work. I'd rather buy one and have my wife mad at me. At any rate, the car is in excellant shape. The only real problem I have is that it idles at 4 grand. Even if I disconnect the throttle cable, 4 grand. I've used my shop manual to try to trouble shoot an "extremely high idle problem"with no success. Any suggestions? I have checked for vaccuum leaks, doesn't appear to be any.

its the choke mechanism, I just got out of the dentist ill see if I can add later

[ITS5GB]

Can you elaborate? I'm not very familiar with the 12a's, all my cars are EFI.

Oh ok, you said GSL which is a carburated 12a model, you have a 84 GSL-SE 13b with EFI, whole different animal, they never put EFI on a 12a. cant help ya with the EFI, maybe one of the 2nd gen guys can.

[ITS5GB]

Sorry if that seemed confusing.It is a gsl 12a with a carb.It is the only car I've had with a carb. The two other cars I have are all EFI.That's why I'm having trouble, I'm not very familiar with the carburator and it's tendencies and problems. Thanks again.

[Tak]

With the car off, take off the air cleaner and shine a light down into the carb--identify wether the primaries (little throttle plates) or secondaries (big throttle plates) are slightly open.
Next look to see what is holding them open. The primaries can be adjusted open at a couple of places. First is the throttle cable attachment to the carb. Second is the idle speed adjuster screw (inboard of the throttle cable cams and below the accelerator pump. If the secondaries are being held open, there is probably a bent linkage or something fouling the secondary throttle vacuum actuator (big housing at the front passenger side of the carb).

Good luck

Tak
#29 ITA
SFR SCCA
(edited to correct my faulty memmory!)

[This message has been edited by Tak (edited June 14, 2004).]

[Quickshoe]

To add, if an idle is that high because of a vacuum leak, it will be a BIG vacuum leak. Look near the firewall on the passenger side off the rear of the intake manifold IIRC. Do you see a 3/8"-1/2" steel line that isn't plugged?

Any of the normal tests for a vacuum leak aren't going to do much good at those kinds of rpms. Number one, with all the racket (I can call it racket now that I have a pissed-on motor) going on at those rpms you aren't likely to hear any hissing. Spraying some carb cleaner or a snuffed out propane torch around at that kind of rpms isn't likely to change the rpm enough for you to notice.

The biggest sign that you have a large enough vacuum leak to cause the rpms to go that high will be the day-glo orange headers from being way too lean. Kill the motor quickly, pray to the Wankle gods that it's not too late and find the vacuum leak before you proceed.

All that being said, TAK's info will probably be the most likely solution. My suggestion is from past mistakes. http://Forum.ImprovedTouring.com/it/redface.gif

[ITS5GB]

Thanks for the suggestions. Hopefully I have some time this evening to check those things out.I'll keep you posted.