Hello,I hope Someone can help me here.i have a 1986 Z28 305 4brl,the car has been tuned up and runs great(124000 miles)the problem is when i start it in the morning it starts out with a high idle like it always has but recently after idleing high for about 1 minute it will idle down to an almost stall,it will do this for another 2 minutes while doing this it also smells ,not like gas but like its not running right, at this time the car runs rough.after doing this for a few minutes it goes back to a regular idle and runs fine.i have brought it to some chevy dealers and i have been told that it is running great and there are not too many ajustments that can be made.it seems they dont want to look into it.i hope someone can help me with this.

thanks
mike

 

Might want to pm Damon, has the following in his sig: "Last remaining QJet tuner on Planet Earth!"

 

Sounds like you might need to adjust the choke engagement period. I just went through this with my Z (good year by the way). You can adjust the length of time that the choke is engaged. Sounds like you need to set it to stay engaged longer.

I'd tell you how, but I never had the QuadraJet on my car so I don't know where to tell you to look for the adjuster.

 

Good thing your Choke acctually works. At one point and time before i bought my 86 irocz, the previous owner had someone do a "tune up" on the engine which included the choke. Instead of adjusting te idle he adjusted the choke as the idle. So essentially i dont have much of a choke but a high *** idle... I have the carb mostly tuned back to where it should be i just have to adjust the choke.

 

i'm not too good on choke diagnosis
but if it is indeed the choke that needs to be adjusted to stay closed longer to allow the car to warm up properly then i can tell you how to do that
when looking at the engine the choke adjustment is located on the left side of the carb, its inside a round housing, it is a bi-metal spring

basically to lengthen the amount of time the choke is active (closed) you need to raise the preload on the spring, to shorten the length of time the choke operates you need to lower the pre-load on the spring
i forget which way raises and loweres the preload but you can feel which way is easier to turn which way is harder

i dont know the exact adjustment procedure but i can tell you what i do that should work
start the car and let it warm up to the idle that you want
when the car is idling the way you want it,and the choke is fully open while it is running, loosen the 3 screws that hold the spring inside the carb, rotate it until the choke just starts to close again, then tighten the screws

that may be over kill but it will work