Very low idle

OK, based on information I received here, I was able to replace the flooded
float, and sort of rebuild the carb on a 1986 Excel. Put it on the car and
it ran better than it had run in many years. Drove it for two days, no
problems. But then, just as I was getting confident in the car again,
another problem crops up.

When coming to a stop, in gear, the idle just keeps dropping till the
engine dies. Removed the battery, and cleared the computer and now the car
seems to run well again.

So, the questions are, 1. is there a throttle position sensor I should be
looking at. 2. Is the computer over riding the carb settings to the point it
kills the engine. 3. If 2, how do you over ride the computer, so that it
learns the new settings.
Thanks in advance for you answers.

 

There's a slow idle adjustment screw. It's been so long since I've even
thought about working on a carburetor, I don't know where to direct you on
the carb. There should be some info on www.hmaservice.com.

 

Been to that site and looked at the info for an 88 Excel (couldn't find info
on 86)
"Slow ideal adjust screw"?? Does not the computer need to be in "learn"
mode first.
OK, let me say that I am not familiar with Hyundai technology. The last ECU
/ carb controlled car I worked on required the ECU to be placed in diag
mode, while I did the settings, then it retained those settings when I took
it out of diag mode. From the Hyundai tech site this appears not to be the
case for this car, is that correct? Is it just a slow idle screw adjust?
What's throwing me here is that I though I set it up correctly, it ran for
two days with no trouble!

 

I don't recall any need to be in any special mode for setting the base
idle. Just hot.

 

Everything you need is in the "Fuel System" chapter of the Shop Manual.
Just follow the instructions on the tech site completely under "Service
Adjustment Procedures". There seems to be 3 adjustment screws (SAS),
and you're not supposed to tamper with #2. And don't forget to check the
voltage output of the throttle position sensor. If that's off, once the
ECU thinks it's "learned" enough, it may be relying on a faulty reading
from it when at idle.

Ignore all the stuff about the FBC checker, since us mere mortals
don't have one.

Bob

 

Thanks, I'll give it a try