Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Stubborn Lean Idle Problem

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Kenth:
Well done!
Just a note: the adjustable airbleed on 1970 and later Pontiac Q-jets adds air to the upper main circuit air bleeds and does nothing for the air bleeds in the idle circuit as it does on 1969 and earlier Q-jets.

And, stinky exhaust is nearly almost the result of a too lean A/F mixture that's not completely burnt and is instead dumped out the exhaust pipes making your eyes tear and you clothes smell like garbage.

71silverstar:
Hmm...that's interesting about the adjustable air bleed.
The stinky exhaust is not the funk you smell when the mixture is too lean...this is that raw gas smell...similar to sticking your nose over the carb after someone hits the accelerator pump.
In my quest to solve the "not enough fuel in transition", I may have overdone the jets/needle sizes and likely my idle mixture is rich.  I noticed the gas smell again in an open parking lot as I walked around the back of the car. 
Looks like I finally get a weekend to get back out and tinker, so we'll see what I find!

71silverstar:
And a follow up...
So, prior to discovering the smashed electrodes and while I was tinkering with all things fuel related, I forgot I increased the size of the jets and had the idle mixtures pretty rich.
Now that the spark is right, I swapped back to the 73 jets and then started the carb tune process all the way at the beginning (vacuum lines plugged, base idle, etc)
Once I finished, the rich smell cleared out and it seems to be right where it should be.
Thanks all for the replies!

Cliff Ruggles:
Good news!

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