[mdhopt36]

Mechanic and I unplugged the forward butterfly valves.
Nice sound when cold, and run in manual mode most of the time.
But when it comes to using a V4 mode, pretty bad.

It also throws a code tied in with the fuel pump module on re-start.

Pf-f-f-ft.
Wonderful
I think GM tied the butterfly valves into the circuit encompassing the fuel pump.
Anyone got a clue how to eliminatee the CEL???.

[breakskeet]

If you unplug the AFM valves you will get a CEL. I do not believe there is a way around this without programming.

You can buy a range device to keep the car in V8 mode all the time.

You are right about how bad it sounds. Sounds like a farting tractor!

[LT4Greg]

Haha...love it!!

[Mark114]

Originally Posted by mdhopt36

Anyone got a clue how to eliminate the CEL???.

To eliminate the CEL you can unbolt the actuators from the exhaust, reconnect the wire harness, and then tie the actuators up out of the way in a safe place under the car. The Range AFM module will keep the engine in V8 mode but you will still get the CEL if the wire harness is disconnected from the actuators. The other option is to tune out the AFM valves.

[cellsafemode]

BTW, for the v6, the afm valves are purely mechanical and can be removed without worrying about a cel. It also doesn't sound nearly that bad but that will depend on your exhaust. For those people reading this with v6's and wondering the same.

[Yanniz]

Originally Posted by cellsafemode

BTW, for the v6, the afm valves are purely mechanical and can be removed without worrying about a cel. It also doesn't sound nearly that bad but that will depend on your exhaust. For those people reading this with v6's and wondering the same.

Would you mind elaborating on this? Removing the valves would prevent the engine going in to V4 mode? How does that affect the exhaust sound and where are the valves located?

Thank you

[cellsafemode]

Originally Posted by Yanniz

Would you mind elaborating on this? Removing the valves would prevent the engine going in to V4 mode? How does that affect the exhaust sound and where are the valves located?

Thank you

The valves don't have anything to do with going into v4 mode. They simply react to exhaust gas pulses and normalize the flow and so the sound.

The valves on the v6 are located after the resonator/x pipe and before the muffler.

There is no need to worry about going into v4 mode on the v6, it doesn't seem to be nearly as annoying as the v8 . But if you want to do so, there are tuning or other electronic solutions you would need to use. Just wanted to note that on the v6, there is nothing electronic regarding the afm valves.

[bignaz]

If you got npp and don't care you can just take the Actuator off the afm vavle or delete the vavle. The. Put then put the actuator on the npp and make a longer pigtail. Normal use npp open highway car goes into v4 the vavles close and quiet. Tap the gas goes back to v8 and they open up.


Same part number 22839592. Haven't done it but I'm going to see if it works. Got the parts ordered for the longer pig tail. Kinda ghetto npp control for non NPP cars using factory components