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Discussion Starter · #1 ·
Ok, I have an ‘16 A8 ATSV with a tune, CAI, TB, BOV, catless DPs. I just had a LPFP installed and I wanted to get it tuned for the CAI and LPFP. The last tune without the LPFP and CAI had me at 500hp.

So the first dyno/tune, the car was at 436. And than the second was another 400 range. I was told after some diagnosing the issue, cycle 4 wasn’t receiving fuel. The injector was replaced and the fuel was better but not great.

Can anyone give any insight to this issue?
 

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Ouch, sorry to hear that.

I'm guessing broken ring land on the piston?

If pieces of the piston and the top ring departed #4, hopefully all they damaged on the way out was the #4 exhaust valves and the turbine wheel... but chances are the debris also got mashed into the cylinder head and dinged up all the valves and valve seats. Is the cylinder wall OK, or did it get scored and damaged too?

If the piston had partially failed and shed a piece of ring land before you went to the dyno, there's a chance the debris could have smashed the #4 injector nozzle partially shut which would explain why the tuner thought #4 wasn't getting any fuel. Any evidence of physical damage on the old injector tip?

And the next question... root cause. Was it originally a #4 injector issue that caused that #4 to run lean and hurt the piston, or was the overall tune too lean and/or had too much timing and cylinder #4 just happened to be the first to let go?

Probably too soon to determine since you haven't pulled things apart yet to assess the damage, but are you planning on doing a rebuild or replacing the long block?

Not a good problem to have.
 

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Discussion Starter · #6 ·
Looked at me engine and it’s not good.

tta1456 as you stated, there may be damage on the exhaust side we don’t know. The cylinder looks ok but with the bore scope we couldn’t look back at the piston on top. There’s a back to the long blocks for this car, so….this might be the end for the ATSV for me. I wanted to drop forged pistons in but we Don’t know the extents of the damage without a tear down.
 

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Could you try to break down what led up to the failure? You would have felt that power loss prior to the latest dyno when the LPFP and intake was installed. Was the car hurt prior to latest dyno? Did you do 1/2 mile runs, or similar?

I'm very interested in learning more of your situation. Looking back, it appears you have been tuned without fuel mods for about 7 months.
 

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2017 ATS-V 6MT CWT Sedan, Tuned 2016 Explorer TT
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Sorry to hear abot your loss. I would also like to understand what happened so as to learn a lesson from this missfortune.
My #1 question is who tuned the car?
 

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Discussion Starter · #9 ·
Ok, back story in the link below.
last year I was at 500hp. See this link….TapOut/Exodus Tune & Dyno (Austin,TX)

So this past Christmas holiday, I purchased ZZP CAI, ZZP LPFP, and TurboSmart BOVs. I installed the BOVs and CAI myself and as far as the LPFP, I went back to my tuner Exodus (really good 👍, they work hand in hand with Scott from TapOut👍). So from New Years week until last week, I would drive my car hard every now and then, you know, to hear the new CAI and BOVs. There were time where my car was in park and the RPMs would bounce around 500-900. So I didn’t think anything of it and kept driving my car. A few days later, I noticed that my car would stay in 4th gear for longer than normal while driving nomal. So I would let off the gas and then the car would finally switch gears to 5th and so on. There were times where I use the steering paddles to change the gears (A8 btw) as well.

So I took my car to my Exodus to have them install the LPFP. I was working towards upgrading the fuel system (after doing some reading, thanks Scott).So after the pump, I wanted to get the dual cam or just full cams, I just didn’t know how the dynamics were going to be with cylinder 4 not working. Exodus did dyno pulls and a tune via Scott. They were all trying to dial in the hp/tq and boost after the pump install. After several pulls and trying to tweak the numbers for boost, fuel, and other stuff, my car lost power. I was now at 446ish/hp. So the tuner used a scope through #4 cylinder and saw this…
Output device Gadget Audio equipment Television set Gas

White Communication Device Output device Gadget Material property
 

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Discussion Starter · #11 ·
Sorry to hear abot your loss. I would also like to understand what happened so as to learn a lesson from this missfortune.
My #1 question is who tuned the car?
It was Exodus in Austin, but they’re not the issue nor was their tune/dyno. I felt issues with the car prior to taking it in for the LPFP install, they were the ones to actually find what I couldn’t.
 

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LF4 Platform Master Tuner
2018 ATS-V M6
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Although we can't tell exactly what happened here without tearing down the engine, we suspect that running the aftermarket intake on a tune designed for the stock intake was the root cause of the problem.

Aftermarket intakes house the MAF sensors in larger diameter tubes than OEM. This makes the ECM read artificially low airflow numbers at WOT. The ECM responds in two ways. First, it 'sees' reduced airflow, so it reduces fuel injector pulsewidths. This makes the engine run leaner than it should. Second, the ECM 'detects' that it's no longer meeting it's torque targets, so it adds boost.

Think about that for a minute. At this point you have an engine that the ECM is commanding to run leaner than it should, and at higher boost than it should. This is a recipe for disaster, and we have replaced many engines for customers who installed aftermarket intake systems without having their tunes updated accordiingly.
 

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LF4 Platform Master Tuner
2018 ATS-V M6
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It frustrates us to no end that two of the most common ATS-V intake manufacturers don't make it crystal clear on their website, and/or in their installation instructions, that aftermarket tuning is required with their intake systems.

Here's what we say on the web page for our intake systems:

Tapout Tuning said:
All ATS-V aftermarket intake systems change the diameter of the tube in which the MAF sensors are installed. This means the ECM will need to be recalibrated via custom tuning. We include these edits at no charge for all Tapout tuned customers.
 

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Discussion Starter · #15 ·
Although we can't tell exactly what happened here without tearing down the engine, we suspect that running the aftermarket intake on a tune designed for the stock intake was the root cause of the problem.

Aftermarket intakes house the MAF sensors in larger diameter tubes than OEM. This makes the ECM read artificially low airflow numbers at WOT. The ECM responds in two ways. First, it 'sees' reduced airflow, so it reduces fuel injector pulsewidths. This makes the engine run leaner than it should. Second, the ECM 'detects' that it's no longer meeting it's torque targets, so it adds boost.

Think about that for a minute. At this point you have an engine that the ECM is commanding to run leaner than it should, and at higher boost than it should. This is a recipe for disaster, and we have replaced many engines for customers who installed aftermarket intake systems without having their tunes updated accordiingly.
It frustrates us to no end that two of the most common ATS-V intake manufacturers don't make it crystal clear on their website, and/or in their installation instructions, that aftermarket tuning is required with their intake systems.

Here's what we say on the web page for our intake systems:
Yeah I read that a few days ago when I noticed that you came out with an CAI. I wish I would’ve bought TapOuts.

Scott, can you list the possibilities that people can do as far as fixing this issue if this happens to them?
 

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LF4 Platform Master Tuner
2018 ATS-V M6
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Scott, can you list the possibilities that people can do as far as fixing this issue if this happens to them?
For anyone who plans to install an aftermarket intake, get your tune adjusted at the same time. Otherwise, stay out of boost until the new tune has been completed. Those are really the only two safe approaches in my opinion.
 

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For anyone who plans to install an aftermarket intake, get your tune adjusted at the same time. Otherwise, stay out of boost until the new tune has been completed. Those are really the only two safe approaches in my opinion.

Call me excessively conservative or even crazy, but I'd go one step further on that recommendation and say even if someone wants to use aftermarket filters in the stock airbox that deserves datalogging at the very least and possibly a tune adjustment unless those exact aftermarket filters have already been tested and are known to be compatible with the stock intake without skewing the MAF readings.

Reason I say that is a while back there was a member here who used AFE drop in filters with the stock tune, and while it ran OK on the street, on track days with extended WOT use at elevated engine temps the ECM was throwing knock sensor codes and putting the car into limp mode because the AFE filters skewed the MAF readings and made the engine run lean enough to induce excessive and prolonged knock during a 30 minute track session. GM ended up buying the car back after the dealer tried multiple times to fix the issue (granted, the user didn't let the dealer know he was running non-stock air filters at the track...)

ZZP puts little ID restrictors in their MAF tubes to reduce the cross section of the tubes where the MAF sensors are and say their intake doesn't need tune corrections compared to the stock intake, but when I tried a ZZP intake for a couple of days and did some datalogging I did see a slight reduction in the MAF reported airmass numbers at WOT compared to the stock intake with clean stock filters. The ZZP intake was showing slightly reduced airmass at WOT compared to the stock intake with clean filters, so things would be running a little leaner. I didn't see a big change in A/F ratio on the wideband so the engine wasn't running excessively lean with the ZZP intake compared to the stock intake. I was running the stock tune when I tried the ZZP intake so the engine running only a tiny bit leaner wasn't really an issue, but it's certainly something I would have corrected in the tune if I kept using the ZZP intake.
 

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Ok, back story in the link below.
last year I was at 500hp. See this link….TapOut/Exodus Tune & Dyno (Austin,TX)

So this past Christmas holiday, I purchased ZZP CAI, ZZP LPFP, and TurboSmart BOVs. I installed the BOVs and CAI myself and as far as the LPFP, I went back to my tuner Exodus (really good 👍, they work hand in hand with Scott from TapOut👍). So from New Years week until last week, I would drive my car hard every now and then, you know, to hear the new CAI and BOVs. There were time where my car was in park and the RPMs would bounce around 500-900. So I didn’t think anything of it and kept driving my car. A few days later, I noticed that my car would stay in 4th gear for longer than normal while driving nomal. So I would let off the gas and then the car would finally switch gears to 5th and so on. There were times where I use the steering paddles to change the gears (A8 btw) as well.

So I took my car to my Exodus to have them install the LPFP. I was working towards upgrading the fuel system (after doing some reading, thanks Scott).So after the pump, I wanted to get the dual cam or just full cams, I just didn’t know how the dynamics were going to be with cylinder 4 not working. Exodus did dyno pulls and a tune via Scott. They were all trying to dial in the hp/tq and boost after the pump install. After several pulls and trying to tweak the numbers for boost, fuel, and other stuff, my car lost power. I was now at 446ish/hp. So the tuner used a scope through #4 cylinder and saw this… View attachment 610435
View attachment 610436
Thank you for letting us know as much as you can up to this point. Sorry about your unfortunate incident, I hope everything works out the best it can for you.
 

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Looked at me engine and it’s not good.

tta1456 as you stated, there may be damage on the exhaust side we don’t know. The cylinder looks ok but with the bore scope we couldn’t look back at the piston on top. There’s a back to the long blocks for this car, so….this might be the end for the ATSV for me. I wanted to drop forged pistons in but we Don’t know the extents of the damage without a tear down.
Sorry to hear the news.
 
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