OBD codes 52 and 71?

JAMESA33

MEMBER
1995 TOYOTA 4RUNNER
3.0L
V6
4WD
MANUAL
200,000 MILES

I am getting #52 (knock sensor) and #71 (EGR system) codes. I can’t find solutions for these repairs, any suggestions?

Saturday, February 18th, 2023 AT 11:38 AM

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,363 POSTS

Hello James,

These codes come up when the EGR valve or ports that feed the valve are clogged or the valve is not working, I would remove the EGR and use a flashlight it inspect the ports also while the valve is off. use this video to test the valve. Also check the vacuum line to the valve:

https://youtu.be/DqUCbbKdWf4

Here is the location of the valve in the images below. Please let me know or upload images of the problem.

Image (Click to make bigger)