Mechanics

IDLE AIR CONTROL VALVE

2004 Nissan Sentra

Engine Performance problem
2004 Nissan Sentra 4 cyl Front Wheel Drive Automatic 52000 miles

My check engine light came on and I found out through an auto parts store that it was the idle air control valve. I have checked everywhere to find this part besides going to the dealership and I can't find it. I have a friend that usually does the work on my car and I was wondering if you knew where I can find this part, how much it would be and how difficult it is to install?

Thanks,
Michelle
Avatar
Meishew
January 6, 2009.



Before you purchase this part, would mind giving us the code(s) that you retrieve from the parts store? We also need to know which engine you have, either 1.8L of 2.5L.

Tiny
Zackman
Jan 8, 2009.
I am so sorry it took me so long to get back to you. I appreciate you being so quick at responding to my email. I went and got the print out of the code and the probable causes. I have an SE which means my engine is a 2.5L. The OEM code is P0507. It states the definition is " IAC circuit condition or idle speed higher/lower than expected". The definition is The ECM has detected that the IAC counts are higher or lower than expected, the engine speed is not in its expected range. The probable causes are
1 - Vacuum leak on engine
2 - Dirty throttle body
3 - IAC motor defective
4 - Poor electrical connection to the IAC valve

The first guy told me that I would need a new valve and that it could not be ordered but this printout is stating there could be other reasons. If you could tell me what would be the easiest and cheapest to fix first to see if that would solve the problem that would be great. I have noticed that my car was idling a lttle weird but I also dont have alot of power, even I can tell and I'm a girl ha ha! Any information or advice you could give would be gladly appreciated. I am only 29 and just got out of back surgery so I am having a really tough time right now and with all of my doctors bills and all I dont have the money to bring my car to the dealer, not than anybody really does. Again I appreciate your help more than you could know.

Thanks again,
Michelle

Tiny
Meishew
Jan 13, 2009.
P0507 - Idle Air Control System RPM Higher Than Expected

What does that mean?

This P0507 code is one that's sometimes triggered on vehicles that have electronic throttle control. That is, they don't have a regular throttle cable from the accelerator pedal to the engine. They rely on sensors and electronics to control the throttle. In this case, the P0507 DTC (diagnostic trouble code) is triggered when the PCM (powertrain control module) detects an engine idle speed that is greater than the desired (pre-programmed) RPM.

Potential Symptoms

Most likely you'll notice the idle speed is higher than normal. There are potentially other symptoms as well. Of course, when trouble codes are set, the MIL (malfunction indicator lamp, a.K.A. The check engine light) illuminates.

Causes

A P0507 DTC trouble code may be caused by one or more of the following: * A vacuum leak
* Leaking air intake after the throttle body
* EGR valve leaking vacuum
* A faulty positive crankcase ventilation (PCV) valve
* Damaged/failed/dirty throttle body
* Failed EVAP system
* Failed IAC (idle air controller) or faulty IAC circuit

Possible Solutions

This DTC is more of an informational code, so if there are any other codes set, diagnose them first. If there are no other codes, inspect the intake air system for air or vacuum leaks and damage. If there are no symptoms other than the DTC itself, just clear the code and see whether it returns.

If you have an advanced scan tool that can interact with the car, command the idle higher and lower to see if the engine responds appropriately. Also check the PCV valve to see if it's blocked and needs to be replaced. Check the IAC (idle air controller) if equipped, verify it's operation. If available, try swapping in a new throttle body to see if that fixes the problem. On Nissan Altimas and possibly other vehicles the problem may be fixed by having the dealer perform an idle air relearn procedure, or other relearn procedures.

***This will be the easiest to do for your vehicle. The actual TSB advises of using CONSULT-II scan tool to test the IAVL, which is only available at the Nissan dealership.***

Tiny
Zackman
Jan 15, 2009.