Originally Posted by hookedon210s

Did the dealer drain the gas tank and clean or replace the filter screen at the bottom of the gas tank? These will get "coked-up" with fuel deposits if the fuel sits for a long time and cause all kinds of problems. Also, I have found that the fuel mixture (duty cycle) may need to be reset several times to get it right due to varying mixtures of old gas and fresh gas and the removal of varnish/gas deposits over time. When the car stalls does it emit black smoke from the exhaust or smell heavily of unburnt fuel? If so, you might want to try tweaking the 3mm adjustment screw 1/8 of a turn CCW to lean the mixture. If this improves matters, the mixture is too rich. If it is worse, try 1/4 of a turn CW (which results in a 1/8 turn rich from your original starting position) to see if matters improve. Once you find you are going in the correct direction, adjust in 1/16 turn increments to obtain a decent idle. Once you get to where the engine will run decently you can then check other posts to adjust the duty cycle properly. Mark