Theta

The CCM keeps an eye on the NPP valves, which is why he's getting this code.

To answer your question, the actuation of the AFM primaries will also actuate the NPP secondaries (if equipped). However, that code will pop since the voltage / PWM signal is reporting the NPP valves as stuck (or in this case, missing).

B Stead

I didn't see this post.

The BB Bullet doesn't have any NPP muffler valves only the AFM muffler valves.

The BB Fusion has both NPP muffler valves and AFM muffler valves
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Theta

Was 99% sure on that one, but always have to cover my bases just in case.

I'm going to guess he removed the valves from the harnesses, causing the code to pop. Simple enough to figure out, a bit harder to fix.

bigdaddyj25

I'm not sure which set of actuators it is called but I removed the set that is furthest from the tip as this is where the bullets had the spot for them to be installed. I simply unscrewed them form NPP exhaust and put them on bullet exhaust and plugged them into the wiring harness.

Theta

Alright, those are the AFM actuators. No problem there.

What did you do with the actuators closest to the tailpipes? Remove them with the system, I assume?

bigdaddyj25

Yes I left them on the original exhaust as there was no where to install. I was told you didn't need them just to wire tie the harness up. Do I just need to remove and get the fusion exhaust? I got the bullets because I like the sound and I prefer it all the time so didn't see the need for the fusion.

Theta

Here's the base problem - by removing those rear "NPP" actuators, the car (Chassis Control Module) believes that they're broken (stuck open, or in this case, missing).

The only way to resolve that code is:

a) to plug the actuators back in, which would be quite clunky and silly,
b) find the correct PWM signal to send back (or perhaps a simple resistor trick),
c) disassemble the NPP valves and cannibalize the computer/electrical section that plugs into the harness (with proper weatherproofing like immersion in PlastiDip or similar), or
d) swap over to the bi-modal system and use the NPP valves as intended.

The problem with C is that I don't have a full schematic of the actual valve, itself. I'm fairly sure you could just get away with removing the butterfly and rod from the motor, but you'd still have an active electrical motor that you would (and I stress this part) need to weatherproof and tie back up into the harness.

As an EE, this doesn't seem like a big deal to me, but it could very well be daunting for some.

I will look into B for you, but as of right now (and we've spent 7 months on this) the BCM (let alone the CCM which we just found out about a few weeks ago) has not been cracked even with quite a few people working on it... So for now, we'd need to 'fool' it. Let me pull the schematics on the valve to the CCM...

bigdaddyj25

Thanks man I'm greatful for your help!!! Could this code be turned off with a tuner like intune?

Theta

Unless Mike knows something I don't about the BCM (which is one of my specialties), [and in this case we actually need to deal with the CCM], we can't touch the CAN/MOST/LIN or any other protocols in the car as of yet (and for those who poke around with this, they actually have the nerve to use all FIVE protocols... that's ridiculous).

It would be interesting if Mike would have a way to kill the P-codes at the ECM level, which may be entirely possible - I'll admit that I know very little about the inner workings of the E92 compared to many here.

Send him a PM with a link to this thread if you want his input - you might just get lucky if he can mask/kill P-codes from the tool. Or at least we might be able to collectively think of something other than the four choices I listed previously.

Theta

Hate to cross-post this, but it confirms my suspicions - an MDI will be needed to clear that code and do the re-learn. Looks like at the very least, these valves are being fed a PWM signal:

Attachment 48372210

bigdaddyj25

So Theta can you recommend a scan tool for me to try this procedure? I'm not very familiar with these.

B Stead

The NPP muffler valves would have to be connected to the wiring and then if they didn't work, a re-learn procedure would be necessary.

The scan tools that I know of make a big deal about support for ABS and airbags. I doubt that they are up on the NPP muffler valves:


.

Theta

You would need a true GM MDI along with an ACDelco subscription to truly have the same level of access as a dealership.

I might suggest you drop in to your dealer's service department and talk to the SM there. They may have the ability to do this for you (turn off the rear NPP sensors) and save you a LOT of money and time.

Otherwise, you're talking $1500 plus a recurring fee to poke around...

Theta

Keep in mind that these tools no longer work with the new systems - an MDI (or for some, a Tech 2 bridge) is required for anything other than basic code scanning.

B Stead

The scan tools just read codes and clear them temporarily. They have a few specifics beyond that such as ABS and airbag. Do ABS and airbag not work beyond 2011 ?

Here is the true bi-directional device:

http://www.aeswave.com/GM-MDI-Tester...322-p8958.html

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Theta

Bingo. ^

B Stead

Gosh, swap this engine in, use the engine controller kit, and throw away the OEM ECM.

http://www.chevrolet.com/performance...gines/ls7.html

http://www.jegs.com/p/Chevrolet-Perf...03674/10002/-1

I picked that engine for the forged crankshaft, titanium connecting rods, titanium intake valves, and cast aluminum pistons.

But it will not work with a plug-in emissions inspection
.

Theta

Wait... you're putting an LS7 in a C7?

bigdaddyj25

Theta - So for option A) if I was to find a good place to mount the other actuators and plug them back in, as long as the ecu sees the motors it will not know whether the valve is actuated or not and it should resolve the code issue? Currently it is just looking for the circuit and it is not there....... at least this is what I'm gathering. I'm not sure where I could mount I will take a look maybe tomorrow but if you think this will resolve the issue it might be the quickest fix for now until something else better can be done. I think its either that or completely remove the bullets and swap for the fusion which I prefer the system to remain open all the time anyway. If you think this will trick the system into working I might try this route for now. Let me know.

Thanks............ Jamie

Theta

A or C would bring the system back 'online' since the CCM would see the unit present again.

Before doing C (if you're the engineering type), try A and see if the code clears. If not, it may truly need the re-learn procedure to clear it.

There's not a lot of room for option A - C would be better if it worked and you didn't want to mess with the weird stuff we're getting into in the other thread.