HELP! Low Idle / P0505

Hello everyone!



First time posting on this super useful site. I'll get straight to the point.

One day my 2011 Taco displayed the check engine light and the slip indicator light together. I stopped at an Autozone nearby to use their code reader and got a 'P0505' error code. After some research I found out that the error code indicates an issue with the IAC. Unfortunately I cant find any information on how to clean it or where to even find it on anything other than a 1st gen. The info I got about the IAC was rolled into other stuff about maybe replacing the O2 sensors or even resetting the throttle sensor.

I guess I'm pretty much all over the place here. Just dont understand why both of those lights would come on together.

Additional info: The lights come on for a couple days then disappear. I've tightened the gas cap and that doesn't help much. The Idle has been super low the past few days.



Thanks!

 

Lots of youtube videos on that

 

Depending on how "froggy" you are, and assuming this is the 4.0L motor, you can remove the throttle body (you don't have a IAC valve) and clean it out with a good quality throttle body cleaner. Don't damage the O-ring seal that goes between the throttle body and the intake plenum.

Then, grab some good quality MAF sensor cleaner while you are at your favorite parts store and clean the MAF sensor.

Have the battery disconnected the entire time. This will provide you with a hard reset of all parameters so the truck can "relearn" the idle speed.

Be VERY careful with the connectors and moving the throttle blade in the housing while you are cleaning it.

Also slap in a new air filter while your at it, OH yeah that Trac lamp being on is just a side effect of the Check Engine lamp..it will go away magically when you fix the truck.

Your code and symptoms are common to dirty throttle bodies and/or MAF sensors.

As Pigpen said, "lots of videos" on the YouTube device.

Let us know what you find.

 

As stated above, There is no Idle Air Control Motor on these engines.

Sounds much like a vacuum leak. Or you are getting unregulated air flow into the intake that the MAF doesn't see.

The P0505 is for a "Idle Control System Malfunction".

DESCRIPTION
The idling speed is controlled by the ETCS (Electronic Throttle Control System). The ETCS is comprised of:
1) the one valve type throttle body;
2) the throttle actuator, which operates the throttle valve;
3) the Throttle Position (TP) sensor, which detects the opening angle of the throttle valve;
4) the Accelerator Pedal Position (APP) sensor, which detects the accelerator pedal position; and
5) the ECM, which controls the ETCS. Based on the target idling speed, the ECM controls the throttle actuator to provide the proper throttle valve opening angle.

MONITOR DESCRIPTION
The ECM monitors the idling speed and idling air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if the following conditions apply:
• The learned idling air flow volume remains at the maximum or minimum volume 5 times or more during a drive cycle.
• While driving at 6 mph (10 km/h) or more, the actual engine idling speed varies from the target idling speed by between 100 rpm and 200 rpm, 5 times or more during a drive cycle. Example: If the actual idling speed varies from the target idling speed by more than 200 rpm
* 5 times during a drive cycle, the ECM illuminates the MIL and sets the DTC. *
: Threshold idling speed varies with engine load.

Trouble areas:

•ETCS
• Air induction system
• PCV hose connection
•ECM

 

Thanks guys,

Going to start by do what Jeffs68 said first thing in the morning. And thanks Jimmyh for the breakdown. While scrambling for info I noticed that there wasn’t a single page or video that mentioned anything about the 2nd gen having the IAC motor. That Trac light threw me through a loop!

I’ll follow up on how the cleaning goes. Thanks again!

 

Problem solved! Cleaned the MAF and throttle body and everything is running smooth. Thanks guys!

 

Cool, a shop would have probably charged a few hundred bucks to do what you did, and maybe would have even tried to sell you a new throttle body.
Thanks for the verification!

 

Thanks guys
My check engine light turn on and I was freaking out had to scan it ASAP as I Driving and got this code super helpful guys

 

Good to hear!