1985 gs

When i come to a stop or push the clutch in the idle drops normally, but after a second or two it drops to almost nothing. Then after a little bit it picks it back up. Seems to be worse when the a/c is off. Also i can feel the gas pedal move down when the idle picks back up. What controls this? And any ideas how to fix it?

1985 gs

sorry about the 2 threads, had computer problem and for some reason they both showed up.

eddierotary

iTrader: (7)

probably the gas cable have too much play, if it have just adjust it.

diabolical1

iTrader: (3)

where does your car usually idle?

Suparslinc

I'd check the anti afterburn hose. It runs from the back of the carb down into the lower intake manifold, and it cracks from being so close to the exhaust heat. Caused my car to die coming to a stop.

cjf

iTrader: (1)

yeah, I have a similiar problem, not major but, when I first start out, come to a stop sign, the car idle goes down and sometimes stalls. after it is warmed it, it does not stall at all. what gives?? Do I have this afterburner thing on my 13b engine?? Is it the cause?? thanks....cjf

Sterling

The brake booster has a vacuum line going to the manifold.
My booster/master cylinder leaks a bit, so I know it should be rebuilt/replaced. My car does the same thing when I stomp the brake at a standstill several times.
I do not know if it is normal. I run no emissions crap, but everything is plugged up well.

As far as the pedal going down - well that's new to me. There's only two things I can think might have that effect, and I don't see how they would do it when you say it happens... The air conditioning dashpot/solenoid...A black canister that pushes the throttle open a bit to compensate for the extra draw of the compressor during idle; And the decelleration dashpot...An oil filled "rebound shock" if you will -with a piston that moves slowly inwards. This allows the throttle to slowly be shut without causing engine and drivetrain 'jutter'.
The decelleration dashpot could be caked with **** and taking a long time to shut that last little bit, but the hunting idle and the dashpot (if that's even the right cause) allowing the pedal to travel some more are two different unrelated things.

...However that's not to say that your problems are not related to each other - Only to say that if the pedal movement is due to that valve, then they are not related.

S'my guess.

Manntis

with the 13B, at startup the engine typically idles at 200 RPM or so. Once it's on its way to operating temp it idles down in the 900 RPM range. If your car is stalling out when cold-idling, instead of the higher idle, maybe a sensor is out?

rankx7

mine is doing same thing

JoeyMazda

It happened to me the other day. I rechecked my whole vaccuum system. This fixed the problem.

Kentetsu

There are now some great troubleshooting and tuning articles available at Sterling's site (idle tuning, performance tuning, etc.). These are very informative, and would be a great place to learn a bit before you dig into this type of issue...

www.sterlingmetalworks.com