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PO171/PO174

z71_offroader
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z71_offroader New Member

z71_offroader

Posted
Posted

Hey guys ive got a 21 trailboss with the 6.2l with just over 13k miles. Right after i bought the truck i add a volant cold air intake and deleted the muffler. After a thousand miles or so i would get a check engine light that would come off and on (soft code). A few months and a couple thousand miles later it starts to idle rough and eventually start stalling at stops. So i had my father inlaw check my codes and it had the po171/po174 (fuel trim system lean). Also had a PO106 and P16F3. I took my truck to the dealer after this and said it needed a new ECU which they replaced under warranty. The service writer said with the intake i will likely always have the PO171/PO174, but the stalling will stop. A couple days later after the new ECU my check engine light came back on. It sometimes idles rough at stops but has not stalled again. 

 

My question is anyone else have these issues after adding a cold air intake? Ive had quite a few vehicles with cold air intakes and never had this issue before which leads me to believe something else is causing.

 

Wanted to pick some of yalls brains before bringing it back to the dealer to have them dig deeper into it. Figured as you can buy a performace package from GM with cold air intake and exhaust would lead me to believe it should run fine without a tune.

shakenfake Senior Enthusiast

shakenfake

Posted
Posted

My brain says take it to the dealer on warranty. CAIs I guess could cause a fueling issue but you'd have to have done like wayyyy more than just CAI realistically it would not cause that. I would switch to the stock intake and see what happens.

fastk9dad Enthusiast

fastk9dad

Posted
Posted

I agree with the poster above, switch the stock intake back on for a couple of a week and see if the issue disappears. If it doesn't then take it back to the dealer with the stock intake on, if the problem resolves well then you know what created the issue.

Anacortes Army Guy Enthusiast

Anacortes Army Guy

Posted
Posted

"Wanted to pick some of yalls brains before bringing it back to the dealer to have them dig deeper into it. Figured as you can buy a performance package from GM with cold air intake and exhaust would lead me to believe it should run fine without a tune."

 

FYI - The GM performance intake does include a reflash as part of the installation.

 

Rad64 Enthusiast

Rad64

Posted
Posted

I installed the GM Performance Intake which is essentially a cold air intake (but aren't they all?). Anyway, I've had mine in for over 10,000 miles and haven't had a single problem. Like mentioned before, when I bought the upgrade, it came with a "free" program flash for the ECU to adjust for the different air flow. Prior to getting the computer flashed, my truck ran a little rough. My guess is you need an update so that the sensors understand the new flow rate of your intake.

  • 2 weeks later...
William Amtower Enthusiast

William Amtower

Posted
Posted

I don’t know if this applies to your setup. I have the GM High Performance option on my GMC Sierra 1500 with the 6.2. It required a reprogram of the ECU at the time of installation. The reprogram comes with the package. It adjusts the ECU for the increase in air intake.

redwngr Senior Enthusiast

redwngr

Posted
Posted

Not sure how this helps with the  aftermarket discussion, but the the factory ordered one gets installed at the dealer, and it requires a different calibration.

 

https://gm-techlink.com/?p=14771

 

GM Accessory Cold Air Intake System Requires Calibration

May 17, 2021

The Chevrolet Performance, GMC and Cadillac Cold Air Intake System (RPO 5W7, RVK) available on 2021 Camaro, Silverado, Tahoe, Suburban, Sierra, Yukon and Escalade models equipped with the 5.3L V8 engine (RPO L84), 6.2L V8 engine (RPO L87) or 6.2L V8 engine (RPO LT1) should only be installed on vehicles that were ordered with the RPO/LPO (dealer installed) option. (Fig. 17) The Cold Air Intake System requires a calibration from the Techline Customer Support Center (TCSC), which is not available for vehicles without the proper RPO/LPO 5W7 or RVK option.

 

F17-performance-air-intake-.pngFig. 17

 

The Cold Air Intake System is a Limited Production Option (LPO) that can be ordered with the vehicle at the time of purchase. It is not to be installed or sold as an Accessory Catalog Offering (ACO), or over-the-counter accessory, as the calibration is not available for ACO applications. If installed on an incorrect vehicle, the Check Engine MIL may illuminate and DTCs P0172 (Fuel Trim System Rich) and P0175 (Fuel Trim System Rich Bank 2) may set.

 

Calibrations for GM Accessories

GM Accessories that require updated calibrations must have the calibrations installed to ensure proper operation of the new accessory components as well as other related vehicle systems, whether it’s an air intake system that includes an ECM update, a front grill package that involves front camera operation, or larger wheels and tires that impact the operation of Advanced Driver Assistance Systems on the vehicle. Calibration updates that are not performed following the installation of an accessory may not only limit system performance, but may also leave the vehicle non-compliant with regional government regulations.

TIP: If programming is attempted before contacting TCSC when installing accessories that require an updated calibration, the Service Programming System (SPS) will not deliver the correct accessory calibration to the vehicle. SPS may display a message advising users that they are attempting to program with the “same calibration” — a warning that the vehicle has not received the required accessory calibration.

 

Installation Information

Installation sheets for GM Accessories can be found in the Accessories Manuals in the Service Information. If the procedures are updated or improvements are made, checking the instructions with each installation will ensure the latest information is being followed.

To locate the instructions, select the year, make and model of the vehicle from the dropdown menus. Next, from the Publication page, select the Accessories Manual link. (Fig 18)

 

F18-acc-3.pngFig. 18

 

Installation Questions

The following sources are available to help dealerships with any questions on GM Accessories.

Accessory Distributor Installer (U.S.) – Contact your local ADI if your dealership has a question or concern related to Limited Production Option (LPO) parts.

Partech – Questions regarding accessory installation sheets, missing kit components, quality issues, and vehicle compatibility can be directed to Partech at 1-855-GMCARES (1-855-462-2737), select prompt 2.

Techline Customer Support Center – Contact TCSC for programming concerns with GM Accessories.

Technical Assistance Center – Questions about the installation of the accessory or help with diagnosing problems related to the installation should be directed to TAC.

For more information, refer to #PIP5805.

RCF71 Enthusiast

RCF71

Posted
Posted (edited)

The GM CAI “reflash” only does one thing - it re-maps the MAF (manifold air flow) sensor to read correctly.  It does not change fueling curves, etc.

 

All of the aftermarket CAI’s are supposedly designed to read correctly (or close enough to correct) without re-mapping the MAF sensor.  Not saying that couldn’t be the issue, as that’s exactly what could cause a lean condition (more air flow than is being measured, hence too little fuel for the amount of air actually entering the cylinders).  
 

I would do the following - first, remove and re-install your CAI, ensuring everything is installed properly, no leaks, etc. (anything not installed correctly can cause this as well).  If that doesn’t fix it, then re-install the factory airbox and see if it still runs lean.  If it runs fine with the factory airbox, ditch your CAI or maybe try a different brand CAI.

Edited by RCF71
  • 3 months later...
z71_offroader New Member

z71_offroader

Posted
  • Author
Posted

Thanks for the info guys, If the gm branded intake comes or does require a MAF recalibration im pretty sure thats what im getting. Im sure it just widens the bandwidth for the sensor. I may reach out to the service writer and see if he can help me out with this, its mostly annoying having the check engine light on since it wont let me remote start...

 

I do plan to get a tune done to it soon, anyone know if doing this would change this? 

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