ok, my choke light is always on in my 85 z28 4-bbl rochester. i know this is the alternator light also. when my car starts up it idles fine(around 750 rpm) once it is warmed up it idles at about 1500-1800?? also when i turn my car off it will diesel and want to stay on. if i want to restart it right away it will not start. i wait about 3 minutes and it starts right up. will replacing the alternator fix all of this?? sorry if i ask so much i don't want to get screwed by mechanix

thanx

 

Check the voltage at the choke wire to make sure it's getting 12v. If not, check the choke heater fuse and relay.

 

if it is not getting 12 volts does that mean it is the alternator?? where is the choke heater relay?? is it under my dash?? how do i fix it if it is a problem?? why is my car dieseling when i turn it off and then not want to start for a couple of minutes??

i know i asked a lot of questions im sorry but i know all of you have good experience with this!! thanks a lot!!

 

If it was an alternator problem you'd probably notice charging problems, but it sounds more like there's a problem with the power to the choke. If the choke stays closed you'll be running really rich and on fast idle all the time.

 

From my old post
My 87 T/A 305/Rocester. After Checking the c/h fan fuse, testing the Alternator , Replacing the electric choke, replacing the choke heater relay, the light still remained ON. There was one thing however that someone mentioned to check and that was the oil pressure switch. I removed the connection and reconnected it on a hunch. Apparently, it was loose and this turned the light out. The periodic diseling problem also went away..bb

The location of the Choke heater relay is in the convienence center (under the dash, drivers side , right leg, knee level). If it's not there then it's next to battery..good luck.

 

That's interesting, I've never seen a wiring diagram for a thirdgen that had an oil pressure switch in the choke ciruit.

 

I agree.... pure coincidence. There is no possible way that the oil pressure gauge sending unit has anything to do with the choke light.

 

I would replace the choke heater relay under the dash. You have to remove a second cover over a few relays after you remove the plastic piece above the drivers knees. The relay is about $10 at a GM dealer. It will probably be green in color.