Boost on, Boost off, and back on??

[B7 Projectile]

So i was driving down the highway Monday and decided to open her up a little by to remind me why i'm dumping so much money into this car. I was in 4th gear under full boost when all the sudden I lost all boost. I let the car slow down back to speed thinking that I blew a hose or something because I thought that I heard a pop when it happened. About 40 seconds after this, the boost comes right back[O_O] and the car drove fine. I pulled the car over and switched it back to stock mode out of 93 and proceeded back to my house. The car is driving fine now with no apparent boost leakage. My mods to date are: Forge DV (installed about 2 months ago), AWE exhaust (7 months), and an APR 93 Chip(3 weeks). Contacted APR thinking that the chip might have influenced it, and they have not heard of such problem before. The car threw no codes. What could have happened?

[IceMole]

Fuel cut? Maybe time for that new pump.

[peta8368]

i'm starting to think APR tells everyone they have not heard of the problem before.

However, this issue has been documented many times on AZ. Your fuel pump can't keep up anymore and is cutting fuels for your car. search for "fuel cut" on the forum and you'll see how many times it has happened and to how many ppl. When I approached APR about the issue 18 months ago, I was told the same thing as they did to you. I don't drive the car as hard now, and the issue has not re-appeared, so I am not too worried about it. But i just think it's bad business practice for APR to tell everyone that when they obviously have heard of similar reports before.

/end complaint

yah, install the new fuel pump, and you shouldn't have that problem anymore.

Peter

[B7 Projectile]

That lasts 40 seconds?? I mean I have felt the hesitation under open throttle but nothing like this. Would the fuel cut cause some sort of a temporary safe mode? Im just a little worried because APR had no clue what I was talking about, they called it "very odd" and told me to contact them if it happens again.

[AudiWxGuy]

Doesn't sound like fuel cut to me. I think you might blown a PCV or maybe a hose connected up to your DV. In stock mode, the parts may be able to hold the lower boost pounds, that's probably why it's driving fine. I would just check everything out. Sounds to me like you went into limp mode. Typically that is a DV or PCV issue, and since it's the forge, I'd be willing to bet it's your PCV....

[B7 Projectile]

Doesn't sound like fuel cut to me. I think you might blown a PCV or maybe a hose connected up to your DV. In stock mode, the parts may be able to hold the lower boost pounds, that's probably why it's driving fine. I would just check everything out. Sounds to me like you went into limp mode. Typically that is a DV or PCV issue, and since it's the forge, I'd be willing to bet it's your PCV....

Thanks for the reply, I had forgot to mention that I had put it back to 93 yesterday and have driven about 85 miles with no problem. Taken that I was not in 4th gear WOT might have had something to do with it, but the car seems to hold boost without any problem just as before. Does our chip include a limp mode, I would think that APR would have sounded to it if it was in the software.

[07-Aythree]

sounds like a fuel cut to me. It used to happen with me a lot. feels like car is stock and then itsback to full power

[B7 Projectile]

sounds like a fuel cut to me. It used to happen with me a lot. feels like car is stock and then itsback to full power

Thats the thing, the car had nothing, I was driving with the amount of power that a lawn mower has, it felt like the safe mode in my Mk4 vr6. Then, after nursing it down the highway, all the sudden i had full boost again, no problems back to normal 93.

[Ski DraGoN]

Cam lobe wear. You will get a CEL pretty soon.
Take it to the dealer. There is a TSB concerning this. I went through this already.

[Ski DraGoN]

http://www.audizine.com/forum/showth...ommon+problems

check out number 4

[B7 Projectile]

Here we go... Ill keep you guys up to date, ill be taking it in on Monday. Wish me luck!!

[Mike@APR]

So i was driving down the highway Monday and decided to open her up a little by to remind me why i'm dumping so much money into this car. I was in 4th gear under full boost when all the sudden I lost all boost. I let the car slow down back to speed thinking that I blew a hose or something because I thought that I heard a pop when it happened. About 40 seconds after this, the boost comes right back[O_O] and the car drove fine. I pulled the car over and switched it back to stock mode out of 93 and proceeded back to my house. The car is driving fine now with no apparent boost leakage. My mods to date are: Forge DV (installed about 2 months ago), AWE exhaust (7 months), and an APR 93 Chip(3 weeks). Contacted APR thinking that the chip might have influenced it, and they have not heard of such problem before. The car threw no codes. What could have happened?

I am not sure who you talked to at APR or how the conversation went so I won't comment about that part. However, what you are describing sounds like a fuel cut. There are many components inolved in fuel delivery on the 2.0T FSI but the problem that has been causing most fuel cuts is wear of the intake camshaft lobe and follower that drive the high-pressure fuel pump. Without any data from your car (stored fault codes, Vag-Com logs, etc.), I can't say for certain that this is what happened but this would be my first guess based on the description. Also, did you check for stored "soft codes" or did you only look for a visible check engine light?

Read the "Inspection" section at the beginning of this document and the Audi TSB at the end of the document for an explanation of the cam lobe wear issue.

http://www.goapr.com/Audi/support/fs...stallation.pdf

If I can be of any further help to you, please let me know. I am on these forums at least once a day but sometimes I get really busy. However, I will be on the look out for any questions from you.

Good Luck,

Mike

[IceMole]

Is there an easy way to get this checked under warranty?

[Mike@APR]

Is there an easy way to get this checked under warranty?

Yes. The very purpose of the factory TSB is to make dealership service departments aware that this is known problem and should be warrantied for cars still under warranty coverage. Of course, your dealership could always blame the issue on your modifications but for the cam wear issue, there have been bone stock cars having this problem (hence the TSB).

[Ski DraGoN]

PM replied

[Ski DraGoN]

http://www.audizine.com/forum/showth...other+fuel+cut

http://www.goapr.com/images/150702_audi_cam_tsb.pdf

[snosk8tr123]

This is an exact description of what happened to my car a lot. I have GIAC software though. It usually happened around 100 mph in 5th gear, but it has happened in other situations as well. It felt like my turbo/cylinders just like shut off for 30 seconds and no matter how far i push the pedal down there was no pull. This has happened to me probably 6-10 times in the last year and a half. I stopped worrying because it came back to full power after several seconds. I might be wrong about this but i kinda noticed that it happened when the car was "overheated" or on a hot day or something. Or a/c was full blast and im gunnning it. But it has happened at night a couple times too so I could be wrong. I have the forge dv and GIAC software

[a4b7]

sound exactly like what im experiencing. I have talk to the dealership and they are not going to look at ANYTHING without a CEL. Even if its worn and about to breakdown, they are not going to look at anything without a CEL. Even since I flashed with REVO, I have not received a CEL...so either the car is running really well and experiencing fuels cuts every so often, or the REVo program is hindering the normal ECU from displaying any problems.

[IceMole]

^ exactly a TSB is not a recall. Which makes me wonder when my warranty runs out am I going to be stuck with a ticking time bomb.