I am getting a P1506 error code?

1998 MAZDA 626

250,000 MILES • 2.0L • 4 CYL • 2WD • MANUAL

RDELAUNE

MEMBER
1 POST

I am getting a P1506 error code. The following have been cleaned: MAF, Throttle Body, IAC, EGR. The respective gaskets have been replaced. After cleaning the parts, the engine was idle "hunting", about 250RPM, so I adjusted the idle. The "hunting" is now very minimal, really not noticeable. I am still getting the P1506 error code. Any ideas??? Does it sound like I need to continue adjusting the idle? Thank you.

Jan 23, 2015 at 2:43 PM

HMAC300

✓ASE Certified Mechanic
48,601 POSTS

e pic for causes but also check for a vacuum leak and air leak between air cleaner and throttle body.

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Jan 24, 2015 at 6:29 AM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

The error code P1506 on a 1998 Mazda 626 indicates an issue with the Idle Air Control (IAC) system, specifically an "Idle Air Control Overspeed Error." So this means the IAC is stuck, I would remove it and clean it here is a guide to help and the location of the IAC in the images below.

https://www.2carpros.com/articles/idle-air-control-valve-service

If cleaning does not work replace the valve. It could be the idle speed adjustment as well. Check out the images (below). Please let us know what happens.

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Sep 27, 2024 at 2:06 PM

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