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CarburetorsCarb discussion and questions. Upgrading your Third Gen's carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
So I have the old "Choke light stays on" issue. '83 Z28 LG4, stock Rochester E4ME carb.
Choke plate doesn't want to stay open even when warmed up, and car idles high, around 1500-1800 rpm... Sometimes when I manually hold the plate all the way open and goose the throttle the plate will stay open and the idle will kick down... but other times the dang choke closes a little and the idle stays high. Worst part is if I shut the engine off while it's idling high, she diesels BADLY.
I checked the alternator: Battery has 12.7V with car off. 14.15V with car running. 14.2V car running and lights on. Gages fuse and C/H fuse are good. With the choke wire disconnected (please see picture) meter is reading 14V... however, when wire is connected to the thermostat tab, I only get about 2.58V. at the tab. So I guess the thermostat is probably the culprit?
I would just like to be relatively certain that I am replacing the right part... thanks for your input.
Bubba, you probably need a new relay. Scoody's car had been "improved" by a previous owner, who just left it out for some random reason.
Sofakingdom, I went back and read one of your replies to "Scoody" more carefully... with the new choke coil, I lined up the notch on the coil to the center mark of the bowl... take a look at the photo if you will...
Car started right up, but still idled high and choke light was still on. Ugh. SOMETIMES when I manually hold the choke plate open and hit the throttle, idle will kick down and the choke light will actually go off!
I have ordered a new C/H relay endwise that connects to the choke coil. We will see on Fri.when I get those parts.
The line-up of the notch is kind of the starting point for adjustment; may or may not be "right" but should be close. The choke blade should close completely at about 70° with no tension, and tension should increase as it gets colder. Adjust it to that point, should already be somewhat close, and see if that makes it operate any better.
You didn't put on a gasket under the thermostat, did you? There should NOT be one. If you did, take it out. The metallic surface around the edge of the thermostat needs to make contact with the bowl to ground it; and the bowl itself needs to be grounded. You can try grounding it with an alligator clip lead and see if that has any effect.
The line-up of the notch is kind of the starting point for adjustment; may or may not be "right" but should be close. The choke blade should close completely at about 70° with no tension, and tension should increase as it gets colder. Adjust it to that point, should already be somewhat close, and see if that makes it operate any better.
You didn't put on a gasket under the thermostat, did you? There should NOT be one. If you did, take it out. The metallic surface around the edge of the thermostat needs to make contact with the bowl to ground it; and the bowl itself needs to be grounded. You can try grounding it with an alligator clip lead and see if that has any effect.
Thank You very much again Sofakingdom! I replaced the C/H relay and the connector to the choke heater coil, as part of the connector was broken. Problem seems to be solved!
From a cold start it takes several seconds to start, and when first started idle seems slightly high (around 2000 rpm), but it kicks down easily and THE CHOKE LIGHT GOES OFF! BTW I did not have a gasket under the thermostat, but thanks for mentioning that tip.
On to the next problem...
hi, why the grat help of @sofakingdom , i think it's better than ever. I have just the rpm to lower and to see if it the thermostat succeed to close back the blade.
I will check next days
04-07-2020, 09:38 PM
