2016 with 18k miles on it.

Brief timeline: Brought car to dealer on 12/14 for transmission fluid change (A8 precaution). Dealer told me the car was pulling a code (no check engine light), asked me about it and I told him I saw no lights. He proceeded to tell me if it wasn't pulling a code now it might soon. They ended up replacing the fuel pump via a special warranty and I was on my way (I noticed a fuel smell I had occasionally at WOT was gone now too).

Fast forward to New Years, the car was sitting in the cold garage for a couple days and I take it out. On my way to get an alignment I did a WOT pull on the freeway and at around 130ish, maybe faster I'm not sure, I get reduced engine power. It was a cool day out in the 40s and the engine temps were all nominal. I limped the car to the nearest AutoZone, buy a code reader and get P228C. I clear it because the dealer is closed and figured I deal with it some other time. Got my alignment, and did come backroad carving with some friends over the weekend. I had zero issue with the car, in fact it ran like a dream. Multiple WOT pulls all throughout the day.

Then today on my way back home from a friend's place I decide to gun it down the empty freeway. I get limp mode again....pull into my garage and read the same code: P228C. Weather is high 40s, low 50s. edit: checked again, also pulling a P0089

Does anyone know the cause? I saw somewhere else it could be a fuel rail sensor issue. Is there a special warranty for this? Is there a reason it wouldn't be checked when the fuel pumped was replaced? I don't want my car sitting at the dealership for another few days, nor do I want to spend big to get the issue resolved if it's not covered under a special warranty (normal warranty is out). The car should be getting modded in the next month or two so I would like any issues resolved by then, Any advice would be appreciated.

edit: below is the freeze frame data. Car was no longer showing P0089.

 

Just gonna bump this once in case anyone has advice from experience or just want to give their 2 cents.

 

Strange, my car is doing the EXACT same thing....

 

I have a 2016 A8 Z06. The code came to me. First the fuel rail sensor was checked. No result in my case. The cause was a small exhaust leak behind the Katalytic Concerter to the X-Pipe. Look at your STFT B1S2 and B2S2 scores. That is not normal. Check to see if you have an air leak. This is what my data looks like after solving the problem.

 

All stock vehicle? I wonder if you got a bad pump. If you're local we can do some scans on it and find out which pump (high or low side) is causing the pressure drop.

 

2016s seem to be the worst of the batch

What is normal if 99.2% isn't? Isn't that a good thing especially at WOT? Im going catless soon anyway.

The fuel pump was replaced because it was cracked, but I'm getting an auxiliary one installed as well. Once the mods go on perhaps the shop will be able to diagnose the problem.

and yes, bone stock until my parts come in tomorrow!

 

While I'm messing with mine and looking at the code mine is actually p228D not 228C.

 

C is too low I believe, D is too high. Wonder how that happens.

 

Change the Fuel rail sensor and see if the issue goes away.
I am not sure if this system has an in line fuel filter but if it does it may be restricted as well.
You are running into a low pressure fuel situation (not enough fuel flow) when the fuel flow demand is at its highest (WOT).

https://www.rockauto.com/en/catalog/chevrolet,2016,corvette,6.2l+v8+supercha rged,3315156,fuel+&+air,fuel+injection+p ressure+sensor,6376

https://www.rockauto.com/en/moreinfo...sn=560&jsn=560

https://www.summitracing.com/parts/ado-12673825/applications/make/chevrolet

 

That happened to my 2016Z once at track. My fuel level was around 3/8-1/4 tank. Once I filled to 1/2 tank, it has never returned. Possibly hiccuped.

 

This is very helpful. I'm going to suck it up and take it to the dealer again.

It's happened to me multiple times on different fuel levels.

 

I held off on taking it to the dealer and just let the shop who is working on my car down here in Houston diagnose it. After putting it on the dyno (560/580, not too shabby), I was told it was the High Pressure Fuel Pump going bad. I was wondering if it was possibly a sensor, or maybe the stock tune on it running too rich, possibly even the stock battery (2016 car) going out and dropping voltage, but I suppose I'll leave it to the more experienced. Is the stock high pressure fuel pump going out way out of the norm I wonder? I'll have to get more information from the shop working on the car whenever I get it back.

 

LOL, did you or they ever change the pressure regulator mentioned in the previous post?

If you all didn't how would they actually know the high pressure pump is going bad?
a bad regulator would give the same indication. What FIP led them to this conclusion?

Chances are that's not the case on a 18000 mile engine/fuel pump. It is entirely possible but not likely.

I wouldn't let then touch it until you change the regulator and see if the problem goes away.
You can change the regulator yourself as it is very easy to replace.

 

The only thing ever changed as far as what the dealer stated was a cracked fuel pump and the pieces that secured it. I hadn't got a code, but the dealer said it was pulling one or would soon. I let them replace it since I was smelling fuel at WOT. Prior to this though (only had the car for a week or two at this point) I had gotten up to 150+ a handful of times. Afterwards though it started giving me the code anywhere between 125-150mph. The shop working on my car said they had a similar case and the issue was the HPFP. When I inquired about how they came to the conclusion I was told it was placed on the dyno and ran through the gears. I didn't really push it because they and the tuner who's dyno and services they use are very reputable. Is the regulator a part of the HPFP? If not it should still give the same issue unless tuned right? Either way they've had my car for a few days now so I'll just leave it to them.

 

Ok...... but putting it on the dyno and running it through the gears is not the FIP for a P228C DTC.
Good luck.