Hooked4Life

I think I saw a post somewhere about an untuned air intake causing the dreaded active handling errors. I was having the issue on a 09 Z06 I just bought with a factory tune, and a K&N air intake. I put on a factory intake, and have not had the problem for weeks now. I did get the AH error one time with a check engine light at the same time, the code was lean bank one and two. That is what made me decide to go to a stock airbox. I was wondering if anyone has experienced this, or could possibly explain the possible relation. The car is still under warranty, so I am holding out on tuning it until I am sure the AH issue is resolved.
Thanks

VETTEPLAY

I have always put aftermarket air intakes on my vettes and have never had this issue nor have I had a single vette owner I know complain of it. Hooked im betting something more is going on here with your car. Sorry I cant be more help but please let us know when you find out the root cause.

bbudman

Never heard of the intake causing an active handling code. As for the lean codes with the K&N I would suggest making sure you don't have an air leak behind the MAF sensor letting in un-metered air. This includes inspecting in and around the throttle body and PVC lines.

Also, if you are using a scan tool to pull your codes make sure you don't allow the cable to come loose while the vehicle is switched on. I had this happen once and received two messages, "service active handling and service anti-lock brakes." I solved the problem by shutting off the car and starting it back up.

Hooked4Life

Just thought I would update this. Been driving the car for weeks now with no more problems using the stock airbox. I am going to put the K&N back on this weekend and see what happens. I hope to see the error return, then start logging as much throttle/maf data as possible. I was seeing the issue at least once a week before, and did not have any unmetered air issues.

Hooked4Life

So I put the K&N on last night, and got the AH warning today after weeks of problem free driving. Same scenario, after 5-10 minutes of idling. Same MAF sensor, only change was the intake. I expect I will continue to see the common occuences as I leave the intake on, we will see. To me, I am sure something is causing the MAF signal to trigger the AH problem.

v3tte

I just cleaned my K&N filter today and had the same problem, my solution was that I forgot to plug the wire back in to the intake. make sure you did that!

Hooked4Life

This may be a bit of a breakthroug in the mysterios AH/TC warning issue. We all know that a bad connection to the steerring sensor, or other failed components of the AH sensors can trigger various failures of the system. These are normally traceable failures, and will trigger failure codes to point you to the right failed component. I am not trying to address those here. What I am claiming is I have found a confirmed means to trigger an AH warning and subsequent shutdown of the AH system with a cold air intake, or more specifically an excessively lean LTFT condition.
Test subject is an 09 Z06, bone stock, except for Corsa's, and a K&N air intake. Factory tune still untouched. All connections and potential for unmetered air were verified as okay at all times. My original symptoms included frequent service AH/TC DIC messages and a TC off light in the cluster. Sometimes with a check engine light, sometimes without. I checked the trouble codes, and it indicated both 1 and 2 bank lean condition in history. The dealer could not figure it out at all, and had little concern for the air intake, possibly because I bought it from them with it on, it may have been different if I added it. I am not sure if it was the body control module, or another module, but they did see an error stored from the event labeled only as "invalid data". They looked it up and it only suggested the same functional tests that they just ran, and all systems passed with flying colors. With plenty of warranty time left, I decided to let them clear everything, and wait and see. The problem came back at least a few times a week, so I decided to get a stock airbox to at least eliminate the lean condition, this completely eliminated both problems to my surprise. I have a pretty deep understanding, and years of experience tuning my own vehicles and never ran into this scenario before. I was still pretty skeptical about the AH warnings being fixed, so I continued to wait. Weeks go by and no issues, I had to dig deeper. I put the K&N back on, and the same day I would see the issue return. I logged the car at idle, as this was the most common time it would fail, and saw my LTFT's were very high. If LTFT's exceed 15% for any period of time, it will trigger a rich/lean check engine code. My crept up to 23-24% and would absolutly 100% of the time knock the AH/TC off line with the trigger of the lean condition trouble code. The first trouble code would record as a "pending" code, thus no check engine light, if I let it sit long enough, it would set the code active, and give the light. This is why I did not always get both failures indicating every time. I suppose the next logical step is to datalog my LTFT's with the factory airbox on it. With this thought, I looked at 5 different logs I collected while using the factory airbox, and they all indicated less than 2% LTFT at idle, and averaged about -2% cruising around. That is a HUGE difference in what airflow is being detected by the MAF. The good news is that this is just a matter of recalibrating the MAF tables to zero out my LTFT's, and all is well. One noteworthy discovery was the positioning of the ECT (throttle plate) during the comparison. With the factory airbox, it would hold about 13% at idle to hold the desired rpm. With the K&N it got down to 8%, this could very well be a trigger point of some kind to fail the AC/TC, or at such an extreme end of the throttle sensor, it could be erratic, although no issues were visible in my logs. I do not know the answer to this suspicion, but feel this is the point where the 2 problems become related. Hopefully this will help a few better diagnose the AH/TC issue.

rdodson

I had the two messages mentioned and am not sure if my scan tool cable got moved during clearing unrelated codes. But next time I started car up I got the two messages. Then I drove for a while and then shut off and and started up again and the two messages were gone. No codes were thrown when I checked.

The unrealted codes I get from time to time are P430 and sometimes P420 - due to - various opinions on forum as to why and how to solve.

rdodson

Interesting analysis. I get the AH light and service vehicle sometimes when I go to WOT in second gear while scanning a log file to tune my car. Am still not absolutley sure that it does occurr when I turn off AH/TC and do a test run from 2000-6000RPM in 2nd gear.

My fuel trims are very good after many many test runs and adjsutments. MY MAF tuning seems quite a bit higher than the Edelbrock E-Force stock tune that came with the ECT scanner.

Car runs great but my gas mileage seems a bit low - like maybe 14 miles to the gallon. Unknown if due to happy throttle response by driver and Edelbrock SC and NPP sounds or what. Driver can't seem to drive like a normal person - according to back seat driver - or in the case of C6 - side seat driver.......

Hooked4Life

So I went ahead and broke the tune cherry. I modified my MAF calibration to adjust for the new air intake, and added in the usual modifiers to better what GM decided was a good compromise, and the car feels great. No more AH issues, or out of whack Long term fuel trims. I decided I would just keep the K&N on and let the tuning begin. I am actually getting improved mileage too. I love HPTuners
I am calling this one case closed. A very obscure, but solidly connected air/fuel ratio issue CAN in fact trigger Active Handling codes. I never would have thunk it if I did not have to fix it.

bbudman

I have followed this thread and glad to see you solved the problem. I too would never had figured fuel trims to be a root cause of the problem but as long as it works, it's all good!

TNTC4VETTE

This happened to me.

It was my alternator dying.

0Brian@RPT

Depending on the intake system, it can cause the service traction control and active handling faults. I have seen these on several Vettes. After some tuning, those issues are resolved.

JoesC5

I got the Service Active Handling, Service Traction Control and a CEL from turbulence at the MAF when I was messing with the air intake system on my 09 Z06.

When I got rid of the turbulence, I got rid of the codes and the surging, without losing my powertrain warranty by "tuning".

DSteck

It's a result of the MAF calibration being thrown so far out that the VE reported airflow no longer matches the MAF airflow, so it thinks the MAF is faulty. It's part of the P0101, P0106, P0121 diagnostic check.

Kexec

I also got the Service Active Handling, Service Traction Control light on my 08 ZO6 last week followed by a constant check engine light. It was time for my annual state inspection so I took it in Monday. The technician found trouble code P0171-Fuel Trim Lean. I also have a K&N CAI. Apparently, there is a service bulletin out on this ( 08-06-04-040). Anyone have access to this bulletin?

The fix was to decrease the gap between the front bumper and the radiator shield using a small piece of styrofoam. No problems since. The funny thing is that I have had the car for more than a year and never had this problem, until last week.