[Boosted D]

I got a 2013 ats last year. Absolutely love the car, but it's been expensive. A few months after owning it I had a p0171 code pop up. Replaced the high pressure fuel pump. A few months later it came on again. Cracked vacuum lines on top of the motor replaced. Then when shifting into 3rd gear check engine light started blinking. Had to shut the car off. Cel said multiple misfire. Still happens sometimes. This year it's been on and off. Replaced all plugs, maf sensor. Last two weeks it hasn't gone off and is down shifting hard from 3rd to 2nd and 2nd to 1st. It's going in the garage Tuesday to get hooked up so they can try and read it. I've got a zzp intake, catless down pipe and Diablo i3 that I want to play with, but not till after it's fixed. I'm kinda leaning towards an o2 sensor. Any thoughts?
Also with the intake and downpipe will I need a custom tune from bnr for the Diablo i3 to get the full effect?
Thanks for any help

 

[Byrdman]

Welcome to the forums! You will get lots of advice. Thoughts? Yes, get a scan to pull codes. Once you know what the car thinks is wrong, repair gets much easier.

 

[Boosted D]

Its saying p0171, lean, bank one. I just cant pin point what it is exactly. I've replaced so many things as i stated before. All i can think is o2 sensor, maybe coil pack, or injector. I really have no clue. I just know there's been many problems with the p0171 code from what I've read.

 

[S.O.G]

That diablo tune might be your issue.

 

[DiabloMike]

OP, as much as it sucks to type this, it sounds like you've lost a piston. I (and too many others) know these symptoms all too well. Do a compression check or get it to a shop to be checked out. Hopefully it just needs pistons and not a new motor.

 

[DiabloMike]

That diablo tune might be your issue.

Hard to imagine something causing a problem that he hasn't even used yet?
Not sure why there's this impression that our tunes are somehow dangerous, but we don't kill 2.0Ts, 2.0Ts kill themselves as evidenced here and hundreds of other examples...

 

[Ragtop 99]

Its saying p0171, lean, bank one. I just cant pin point what it is exactly. I've replaced so many things as i stated before. All i can think is o2 sensor, maybe coil pack, or injector. I really have no clue. I just know there's been many problems with the p0171 code from what I've read.

a small vacuum leak leak after the MAF can cause this. Check that the intake tract and the intercooler for cracks, loose hoses, etc.

 

[DiabloMike]

Any update OP?

 

[blacktone]

any update

 

[Slawrence003]

I got a 2013 ats last year. Absolutely love the car, but it's been expensive. A few months after owning it I had a p0171 code pop up. Replaced the high pressure fuel pump. A few months later it came on again. Cracked vacuum lines on top of the motor replaced. Then when shifting into 3rd gear check engine light started blinking. Had to shut the car off. Cel said multiple misfire. Still happens sometimes. This year it's been on and off. Replaced all plugs, maf sensor. Last two weeks it hasn't gone off and is down shifting hard from 3rd to 2nd and 2nd to 1st. It's going in the garage Tuesday to get hooked up so they can try and read it. I've got a zzp intake, catless down pipe and Diablo i3 that I want to play with, but not till after it's fixed. I'm kinda leaning towards an o2 sensor. Any thoughts?
Also with the intake and downpipe will I need a custom tune from bnr for the Diablo i3 to get the full effect?
Thanks for any help

 

[Slawrence003]

I would love to hear what you find out. My 2013 ATS is throwing the same code. I replaced the MAF sensor but it is still throwing the code. A couple weeks ago I took mine into dealer. They fixed an exhaust leak and changed my oil. A couple hours after picking it up from them the car throws code P0171. I took it back and they told me it was MAF sensor and wanted $272.00 to replace. I picked it up and replaced it myself for $75.00. Engine light went off for about a half hour but came back on.

 

[CBcadiATS]

here is what the repair manual for our car says:
P0171

• Mass air flow (MAF) sensor signal skewed-If the Short Term Fuel Trim parameter changes greater than 20 % when the MAF sensor is disconnected, refer to DTC P0101 See: P0101.
• Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis See: Powertrain Management\Fuel Delivery and Air Induction\Fuel\Testing and Inspection.
• Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust See: Engine, Cooling and Exhaust\Exhaust System\Testing and Inspection\Symptoms - Engine Exhaust.
• Malfunctioning fuel injectors-Refer to Fuel Injector Solenoid Coil Test See: Powertrain Management\Computers and Control Systems\Testing and Inspection\Component Tests and General Diagnostics\Fuel Injector Solenoid Coil Test.
• Vacuum hoses for splits, kinks, and improper connections
• Insufficient fuel in the tank
• Low fuel pressure-Refer to Fuel System Diagnosis See: Powertrain Management\Computers and Control Systems\Testing and Inspection\Component Tests and General Diagnostics\Fuel System Diagnosis.
• Vacuum leaks at the intake manifold, the throttle body, and the injector O-rings.
• Leaks in the air induction system and the air intake ducts
• Leaks in the components of the vacuum operated engine mount system
• Missing air filter element
• Cracked EVAP canister
• Evaporative pipes obstructed or leaking
• The crankcase ventilation system for leaks-Refer to Crankcase Ventilation System Inspection/Diagnosis (LCV) See: Powertrain Management\Emission Control Systems\Positive Crankcase Ventilation\Testing and InspectionCrankcase Ventilation System Inspection/Diagnosis (LTG) See: Powertrain Management\Emission Control Systems\Positive Crankcase Ventilation\Testing and Inspection.

 

[CBcadiATS]

just a thought because I replaced all sorts of sensors hunting down the culprit for a lean fuel mixture. I found that oil was coming up my intake track and splashing on the turbo sensor in the intake tube from the intercooler to the throttle body. check that sensor if there is oil on the sensor it will not read the correct temperature for the air coming out of the intercooler and will change the amount of fuel used. just a thought. i clean mine every month.

 

[Slawrence003]

Thank you! I will check that out this weekend.

 

[Boosted D]

Sorry i haven't responded. I've been so busy with work. So i ended up replacing both o2 sensors. Didnt fix anything. Brought it to the dealership and found it was a small vacuum hose under the car that fell off. Twice its happened in the last month. It still has a blinking cel when it shift from 2-3 gear when im getting on it, but it goes away after 30 seconds. Guessing its just a misfire.Now the car is shuddering in low rpm. I was just on here reading of torque converter problems and failed transmissions. Not excited for the next step

 

[GeorgeMMA]

I got a 2013 ats last year. Absolutely love the car, but it's been expensive. A few months after owning it I had a p0171 code pop up. Replaced the high pressure fuel pump. A few months later it came on again. Cracked vacuum lines on top of the motor replaced. Then when shifting into 3rd gear check engine light started blinking. Had to shut the car off. Cel said multiple misfire. Still happens sometimes. This year it's been on and off. Replaced all plugs, maf sensor. Last two weeks it hasn't gone off and is down shifting hard from 3rd to 2nd and 2nd to 1st. It's going in the garage Tuesday to get hooked up so they can try and read it. I've got a zzp intake, catless down pipe and Diablo i3 that I want to play with, but not till after it's fixed. I'm kinda leaning towards an o2 sensor. Any thoughts?
Also with the intake and downpipe will I need a custom tune from bnr for the Diablo i3 to get the full effect?
Thanks for any help

I had the same issue about 2 months ago and sad to say it led to me finding out I had cracked pistons. Cadillac pistons from the year 13-15 are not the best. They upgraded them for the 17+ models. And I read that people are assuming its the tune. No its not my car was stock when it happened.

 

[Boosted D]

I had the same issue about 2 months ago and sad to say it led to me finding out I had cracked pistons. Cadillac pistons from the year 13-15 are not the best. They upgraded them for the 17+ models. And I read that people are assuming its the tune. No its not my car was stock when it happened.

What did you end up doing? I've thought about that as a possible option to why its acting like that, but I've also read about the transmission shudder and the problem being the torque converter.

 

[DiabloMike]

Sorry i haven't responded. I've been so busy with work. So i ended up replacing both o2 sensors. Didnt fix anything. Brought it to the dealership and found it was a small vacuum hose under the car that fell off. Twice its happened in the last month. It still has a blinking cel when it shift from 2-3 gear when im getting on it, but it goes away after 30 seconds. Guessing its just a misfire.Now the car is shuddering in low rpm. I was just on here reading of torque converter problems and failed transmissions. Not excited for the next step

Seems the dealer didn't properly diagnose the issue. Still sounds like a cracked piston to me.

 

[Boosted D]

Seems the dealer didn't properly diagnose the issue. Still sounds like a cracked piston to me.

Yeah. I'm bringing it to the dealership next week for a diagnosis. Looks like i might be sticking a few more grand into it. If it is a cracked piston wouldn't i be seeing a power loss? I'm confused as to why it only gets a cel when shifting from 2-3 or 3-4. As for the shudder, I'm sure that's the torque converter as I've read in many other posts about transmission shudder.

 

[DiabloMike]

The 2nd time it happened to me (cracked piston less than 5K miles after the first one was replaced) it would sometimes run fine for days on end, then randomly I would get some misfires and shudders as a result. Occasionally it would light up stabilitrak at low speeds then stall or try to die. I was not happy about the situation and didn't hesitate to go WOT and it would feel fine most of the time. I drove it like that for probably 45-60 days before I bothered to take it back to the dealer.
When the first piston failed it was barely driveable at all.
When it happened the 3rd time I barely made it home and once I got it in the driveway it wouldn't even start back up (piston killed the block).

A compression test should have been performed and will confirm the issue in most cases. The piston usually cracks near the skirt. My first one was literally falling apart at the bottom of the skirt.