AFM valve gremlins
Thread Starter
Intermediate
Joined: Mar 2017
Posts: 40
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From: Boyd Wisconsin
AFM valve gremlins
Hey everybody! I put a B&B Fusion on my 14 Z51 a few months ago and everything was fine at first. 2-3 weeks ago I was out doing some spirited driving and had a great time. The next morning when I started the car, I had a cel for the AFM valve. I’m fairly certain that I melted one of the actuators, but what I’ve also noticed is the car won’t go into manual mode. Is this normal or do I have another issue somewhere?
Le Mans Master
Joined: Dec 2014
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From: Northeast
That’s why they deleted them on the Z06. While uncommon for the LT1, it’s not impossible... I believe that the GS doesn’t have them either. I suspect that their longevity will be tested, particularly on earlier MY C7s. If you have an OBD2, you can clear the code, unplug the harness, and then reconnect to see if it resets. Unfortunately, if it’s fried, then you’ll have to repair or replace.
I remember reading on here a while ago that you can also trick the ECU by manipulating the harness, but don’t remember how this was done. Try searching “AFM valves” in ‘16 or ‘17.
I remember reading on here a while ago that you can also trick the ECU by manipulating the harness, but don’t remember how this was done. Try searching “AFM valves” in ‘16 or ‘17.
Thread Starter
Intermediate
Joined: Mar 2017
Posts: 40
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From: Boyd Wisconsin
Pro
Joined: Mar 2002
Posts: 576
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From: Woburn MA
Happened to me Friday
I was at Palmer raceway when I got the MIL and some god awful noises out back, I didn't know what it was and the codes came back unknown, so I called it a day.
Turns out you can pull fuse #32 and and that will stop the actuators from cycling on startup, you will continue to have the MIL.
These valves come into play when the vehicle goes into V4 mode, I have a Range device so I don't need no stinking AFM Valves
There are several choices
Good luck
Turns out you can pull fuse #32 and and that will stop the actuators from cycling on startup, you will continue to have the MIL.
These valves come into play when the vehicle goes into V4 mode, I have a Range device so I don't need no stinking AFM Valves
There are several choices
- Replace the valve actuators and expect it to happen again
- Leave them alone and tune them out, many have done that
- Install new actuators (warranty?) and space the mounts out with washers, the actuators are then far enough from the heat but they WON'T operate the valves ( the valves are sprung open the actuators actually close them
- Some people remove the actuators from the mounts and strap them somewhere away from the exhaust heat so they can go through their startup ritual without having any impact on the valves
Good luck
