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Pelon916 · 07-23-2003, 02:17 PM

This is a strange problem and I'd like some advice...

Please bear in mind that this problem has been happening since I got my truck, with 2 totally different carbs and intake manifolds.

Ok... my truck's idle is very high when it's cold, as though the choke were on.. but the choke is not even hooked up. If I tap the pedal the idle will drop to normal, but if I give it even the slightest bit of gas the idle jumps back up and stays there.
When I say high, I mean it will chirp the tires if I put it in gear, and if I drive it like that I can hardly stop because the brakes have to fight the engine.

The new carb and intake manifold did not change the problem at all. It is exactly the same.

When the truck is warm this does not happen. The idle is perfect. The throttle is not sticking, it works perfectly as well. This also happens if I manipulate the throttle directly on the carb with the linkage unhooked.

It has been suggested that I could have a vacuum leak to the tranny.. but I was under the impression that a vacuum leak would lower the idle, not make it sky high.

A problem with the distributer was also an idea. Maybe the vacuum advance or something is screwed up. But when the truck is warm it is fine.

Also, when I say cold.. I mean it's this way for about 10 minutes of running or more before it acts normal. After that it's fine for the rest of the day.

Any ideas?

07-23-2003, 02:17 PM	#1
Pelon916 Registered User Join Date: May 2003 Location: Sacto, CA Posts: 39	Wierd idle problem... This is a strange problem and I'd like some advice... Please bear in mind that this problem has been happening since I got my truck, with 2 totally different carbs and intake manifolds. Ok... my truck's idle is very high when it's cold, as though the choke were on.. but the choke is not even hooked up. If I tap the pedal the idle will drop to normal, but if I give it even the slightest bit of gas the idle jumps back up and stays there. When I say high, I mean it will chirp the tires if I put it in gear, and if I drive it like that I can hardly stop because the brakes have to fight the engine. The new carb and intake manifold did not change the problem at all. It is exactly the same. When the truck is warm this does not happen. The idle is perfect. The throttle is not sticking, it works perfectly as well. This also happens if I manipulate the throttle directly on the carb with the linkage unhooked. It has been suggested that I could have a vacuum leak to the tranny.. but I was under the impression that a vacuum leak would lower the idle, not make it sky high. A problem with the distributer was also an idea. Maybe the vacuum advance or something is screwed up. But when the truck is warm it is fine. Also, when I say cold.. I mean it's this way for about 10 minutes of running or more before it acts normal. After that it's fine for the rest of the day. Any ideas?