I've got a 12a '85 1st gen. that last summer I took the cats off of and put a bonez down pipe on. I then disconnected the air pump and it rans great. Recently, I'll start the car with the choke and drive it. When it comes off the choke and I stop at a stoplight it will go to real low rpms and die. If I turn the car off for a few seconds and restart it, it idles fine. Anyone got an answer for this one. Yes, I've tuned the idle mixture screw and set the idle at around 900rpm. Sometimes when its on the choke and warming up in the driveway it will cycle up and down in rpms again and again.

 

accelerator pump or adjustment?

 

When you remove the air pump, there are some hoses that need to be capped or plugged, otherwise they cause massive vacuum leaks. Did you do this?

 

Everything is still connected except the airpump hoses that go to the cats. The emission rats nest is still intact, so why would I have a vacuum leak with all the hoses still connected? Why would it run great for 6 months then this? It runs great except for this one thing.(100k on car.) Why would stopping and turning the car off bring the idle back to normal? If its an adjustment, what adjustment, where? I've got the idle mix screw set just right and also the idle screw. What other adjustment would do this. With turning the car off, this sound electrical/carb/sensor. Any Miki carb experts out there?

 

Are you tuning your idle with the choke on?