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lx 1986
12-12-2015, 02:24 PM
I have an 86 Honda accord lx with a 2bbl keihin carb, auto trans. The carb is a new remanufactured carb and the idle goes up and down. My mechanic said the idle couldn't be adjusted because he thought something was wrong with the throttle cable. Had him change cable and problem is still there. In the morning at cold start the car will start but the fast idle doesn't hold and the car dies. I restart the car and have to hold my foot on the gas and wait for the temperature to go up and then the fast idle will hold at 2500 rpms but will not go down on its own until I tap the gas pedal and then it drops to below normal idle but nothing in between. The other problem I'm having is after the car has been driven awhile I restart it and it goes into fast idle like on a cold start. When the car is warm and been driven I noticed that when I turn on the ac and then turn it off the idle will rise and hang above 1000 rpms and will not come down. I found that if I disconnect the air temperature sensor that's in the snorkel of the air cleaner the idle will drop back to normal. If I restart the car the idle will not go into fast idle either. The air temperature sensor is new. It seems that I only have the idle problems when the air temp sensor is connected. Any ideas of what is wrong.

conozo
12-14-2015, 02:14 PM
-Have you checked for vacuum leaks?
-Does the car idle fine when you have the air conditioning on?

lx 1986
12-17-2015, 05:14 PM
I have just checked by looking visually at the hoses for any cracks or loose hoses. I don't have a vacuum pump. I was going to spray with carb cleaner tomorrow. Yesterday I was looking at the snorkel of the air cleaner to see if there was a problem with the door opening and closing. I found the door was jammed and wouldn't open on its' own when the air cleaner was turned upside down. I found someone had damaged the air cleaner and knocked it out of alignment so the door wouldn't open. I fixed that and found they had also broke the hot air pipe connection. Fixed that also. I thought maybe this was the problem. I was wrong. To answer the question about the ac. Yes and no. Thinking I might have fixed the problem I put the air cleaner back on and drove it. Still having the same problem. I tried to adjust the idle again and the ac. Sometimes the ac will make it idle higher and hang above 1000rpms in park and when I turn it off idle won't come down. If I put it in drive with ac on sometimes it will be alright and other times it will drop to low. I have this problem even if I don't use the ac.

lx 1986
12-20-2015, 03:44 PM
I checked for vacuum leaks with carb cleaner today and no leaks. Is there any valves, sensors, etc I should be checking for connected to the fast idle and warm idle?

Dr_Snooz
12-26-2015, 07:23 PM
The carb is bristling with vacuum actuators, solenoids, electric valves and all kinds of good stuff that can go wrong. Download the manual (https://www.dropbox.com/sh/vtyhl48z5uftmt1/AAA0VFYqWyfZ35Nvudl0xk_Oa?dl=0), read up, and start testing them.