I just cleaned my throttle body, but I had a problem before, where while driving, the idle would go really high. I could usually hit the gas pedal and it would slow down. I just figured out that vacuum hose thing I posted about a few days ago, and took it for a test drive. When I got to the stoplight by my house, the idle cranked up, and would not go down, even after hitting that gas pedal a few times. So, I turned around. It also has a major lack of power now too, but I'll deal with that later. I popped the doghouse and air filters, and started it up again and it was idling normal. I can plainly see the idle actuator moving around. I dont know if its getting stuck, or if the electronics are doing it, or some other reason... Should I grease the actuator piston?

Whenever it does this, its usually after about five minutes of driving. I think it eventually goes away though.

Any ideas?

 

Are you sure you do have multiple vacuum leaks?

 

Its an old van . There probably is.

Let me ask you this: What vacuum related component could be making the idle actuator do that? maybe I could narrow down a vacuum leak if I knew. My list of possible causes: Bad idle actuator, Bad throttle position sensor, ECM, (god I hope not)

I ordered a few cheaper components from Rockauto, like a Fuel pressure regulator and air temp sensor and a throttle position sensor.

I feel a little overwhelmed trying to find vacuum leaks, to tell you the truth....

 

Well, I checked out the vacuum lines, and none looked bad, but I replaced all the bigger ones coming from the throttle body. Took a quick test drive, and there is no high idle, so far, so hopefully that was the ticket. I do remember it didnt always kick into high into high idle mode though...

 

Have you tried this?


Using the carb cleaner, check everywhere vacuum could leak.

Also a bad coolant temp sensor - or more specifically a malfunctioning one can do this too...

Bro - it can be a lot of things...you have to take a step by step approach.