N/A '83 Choke problem

[widge]

Hey all.

I have a non-turbo '83 Limited that's been giving me trouble lately. It's been extraordinarily anemic since I swapped the motor from a '77 or '78 Monza into it last August, but that's not really the issue right now...

My oil/choke light (which, might I add, I consider to be the absolute worst combination of idiot lights on the planet) had started going on intermittantly recently. I could get it to go off if I gave it a lot of throttle, but as soon as I backed off and started to slow down, it came back. It seemed to come and go as it pleased and never really affected performance any more than was already affected, and it didn't make any more noise or vibration, so I just assumed it was the choke sticking as always.

In the past few days, though, it has started to come on solid and not turn off, no matter what I do.

It's probably just a coincidence, but this has coincided with some torrential rain that I had to drive through in Central IL in the past week or so.

Anyway, so I took a look at my old carb that was on the motor, and inspected it. It was leaking gas terribly, and there was varnish everywhere, and the choke had never really liked working to begin with, so I bought a rebuilt replacement from Autozone and installed it. I have a lot more power now, and it no longer stumbles or bogs anywhere in the RPM range like it used to. However, the oil/choke light is still solid, and my cold starts are terrible.

No matter how much adjusting I do, I have either a very fast idle, or a surging low idle that tends to kill the car when I put it in gear unless it's warmed up.

I suspect it has something to do with the computer-controlled portion of the carb, since everything seems to be tuned properly with respect to the mechanicals. Unfortunately, I don't really know where to start to fix anything about the electronic part.

I'd appreciate any help/suggestions you guys might have.

Thanks.

 

[widge]

bump

update:

It seems like if I drive it for more than, say, 45 minutes, it starts to act up again and want to die as if it's being choked. But any time between warm-up and that 45 minute mark it's great.

Is the computer screwing with the choke or timing or something to overcompensate after prolonged driving maybe?

Anybody have any ideas at all?

Thanks again for any help.

 

[b4black]

Just to add to the choke and oil, I believe a bad alternator will light this light (diode trio in my case). I had it happen on a '81 El Camino. The alternator was going and it caused the choke light to go on (maybe becuase it's an electric choke?).

The pattern of the light being on and off is just like what I had. I know it sounds weird, but that's what it was. Might be worth a quick check. Good Luck.

 

[84ZZ4]

The computer doesn't control the choke at all--if it did, I'd be in trouble, since I've been running sans ECM for several months. In fact, I can't think of any situation where the oil/choke light being ON when it shouldn't be indicating a problem with the choke.

The way it works is, light off when it shoud be on (IE key on engine not running) = choke problem. Light on when it should be off is an oil pressure problem.

I've got some troubleshooting diagrams here:

http://www.camaro.dnsalias.com:8008/Reference/85-olds-choke-1.jpg
http://www.camaro.dnsalias.com:8008/Reference/85-olds-choke-2.jpg
http://www.camaro.dnsalias.com:8008/Reference/85-olds-choke-3.jpg
http://www.camaro.dnsalias.com:8008/Reference/85-olds-choke-4.jpg

 

[widge]

Thanks for the suggestions so far, guys.

It no longer looks like any choke problem, since the choke seems completely operational. However, the problem is now that my car just won't idle.

I've replaced cap, rotor, plugs, and wires and found that one of my wires was sort of frayed, and got rid of a little bit of missing that was going on at low rpm, but the car is barely driveable. It quickly stalls out at idle for what seems like no reason.

I think I'm just going to end up taking it to a mechanic since this seems to be out of my hands now, but if anyone has any suggestions, I'd appreciate anything.

Thanks.

 

[widge]

Final update.

Well, I took it to the mechanic today, and a half-hour and $34 later, I find out that the left venturi in my *brand new* rebuilt carb was completely toasted and just dumping gas into the motor at idle and flooding it out, but the accelerator pump worked fine, which is why the thing ran just fine once you got on it.

Thanks for the suggestions, guys. It looks like sometimes the simplest solution is the right one, and I'm never going to discount something as being the problem just because it was new.