Hi all,

My '84 GS is having an idling issue. I've been checking out the 1st gen specific FAQ page and think that the car is exhibiting signs of either too much carbon buildup or a vacuum leak. Is there anything else I should be looking for as a possibility for the problem besides these two things?

 

Can you describe what it's doing?

 

When I come to a stop sign or light, the car stalls almost immediately unless I pull out the choke. I find that if I stay in 3rd or 4th as I come to a stop it sometimes stops the stall from happening, but the RPM needle goes nuts and bounces from 0 to 3k or anywhere in between when it does idle.

 

That sounds like an ignition issue. When the tach bounces it's usually a problem with the trailing ignitor. The trailing ignition does most of it's job at idle to low rpms. If it isn't working, symptoms can be irradic behavoir at idle or it may act like it's flooding.
There are much more knowledgable ignition folks here than me who will hopefully answer.

 

You should probably start by verifying that you have spark on both leading and trailing plugs.

Is this a problem that suddenly started?

 

Check your trailing ignitor.

 

The problem has been sort of ongoing...I bought the car in March and have autocrossed it four or five times since then. It started doing this when I first bought it, then seemed to run okay for a month or two, and it's been going again for a month or so...

I'll check the plugs in the next day or two and get back to you guys...thanks.

 

i had the same problem it was it is a valve around the carborator i got it changed but didn't help. but what did help was plugging one of the vaccum line in the air filter.

 

Yes Id check that trailing ignitor, just because of the tach bouncing. Im assuming that it isint coinciding with the engine actually bouncing in rpms. There are certain conditions that the trailing igniter does and doesnt operate, some of which is controlled by by switches in the transmission. Any of the manuals spell out how to test this. It still could be a vacuum leak that is on something that is only operating in these circumstances, like the shutter valve.