Fast Idle

[96-2D-Hoe]

My truck is sometimes idling at 700-750 rpm after it's warmed up. If I'm driving for 20 mins I'll notice it once or twice. Normally idles at 600 rpm.

I've never changed the IAC valve, I did cleaned the MAF sensor and the throttle body a couple years ago, air filter is K&N and clean. Truck doesn't go far and It's probably done less than 5k miles since I cleaned everything.

Any ideas?
Thanks

 

[Big Mama]

Usually a high idle is extra air getting in somewhere. With it being 100-150 higher it could be as simple as the weather. Check your vacuum lines and the intake clamps

 

[96-2D-Hoe]

Was idling low around 550 when I pulled into my parking space after driving around for 45 mins last night. Headlights were dimming until I touched the accelerator. Have been meaning to check fuel pump pressure but I don't think that's it.

 

[swathdiver]

Clean the IAC, check it's operation with scan tool. Same for MAF, make sure Mass Airflow Sensor is not contaminated with K&N filter oil.

 

[96-2D-Hoe]

Usually a high idle is extra air getting in somewhere.

I broke the hard plastic hose going to the evap canister when I swapped out the steering gear. I'd used a rubber cap with the top cut off as a straight connector but it's fallen apart for some reason, probably was too tight.

Still haven't driven it yet though

 

[drakon543]

its usually better when it tight

 

[96-2D-Hoe]

its usually better when it tight

It was from a vacuum line kit I've had for 20 years. It was very tight, i had to lube and force it together. It had split all the way across. I just left it on and taped it up with electrical tape for now.

 

[drakon543]

well a little lube and forcing it in and....... i dont know your making it to easy here.

 

[Big Mama]

Good to hear you found the problem and a fix for now.

 

[bigfootchiro]

well a little lube and forcing it in and....... i dont know your making it to easy here.