2001 2.7t power loss - no whine - please help

**B5in** · 11-17-2008 10:08 AM

Well intermittently when I take off from a light the car feels like it has 0 boost, it only seems to do it from a start & it only does it once in a while, but is starting to do it more & more. It doesn't make any weird noises, doesn't smoke, it doesn't hesitate at all & the CEL hasn't come on yet :confused:

any ideas?

car in question:

**blmlozz** · 11-17-2008 10:11 AM

check common 2.7T wear items first I would say. Ie vacuum lines, DV's, TBB, DBW pedal actuator (ocassionaly these will go and will act funky like you're descibing, however these cause CEL's.). Not sure if the all-road had an F-hose.. but begining mid-2001 the S4's were sold with the revised vacuum routing to eliminate it. If you have access to a CEL checker or vag-com, there might not be an active CEL but there could be 1 or more in pending status and these would be able to be read with a decent checker.

**B5in** · 11-17-2008 10:14 AM

I just read about the "f" hose, I am gonna check that out to if I have it, I did recently replace the diverters to new 710N's & it was running fine for a while after that so I am pretty sure I tightened everything down pretty well, but I will be doing a pressure test just in case asap

**B5in** · 11-17-2008 01:33 PM

I just went outside & confirmed I do not have the "f" hose.

My friend suggested that it may have a clog in the oil stream & maybe one of the turbo's isn't getting any oil so it isn't spinning freely, but if that were the case wouldn't I get a dumby light for oil pressure?

**B5in** · 11-26-2008 11:41 AM

***UPDATE***

well it turned out to be a faulty brake light switch

dealer wanted $180 to put a new one in...so I purchased one online for $22 shipped & put it in myself last night in about 30 minutes

crazy how such a little thing like that can affect the way the car runs so much

**2.7avant** · 11-26-2008 12:49 PM

I can see how that could happen.

On my 1.8t Jetta I was having an issue where my EPC light would come on and I would be running on less than limp mode. After a while my brake light switch went bad and when the EPC light came on I would actually have no power at all. Id hit the gas and the car wouldnt move. I ended up changing the Gas Pedal, Brake light switch and Throttle body which fixed all of the issues.

**B5in** · 11-26-2008 01:50 PM

yeah my epc light, abs light, & adj. suspension light would all come on which would put the car in limp mode, but not all the time so that's why it was throwing me through a loop.

**ThirdROC** · 12-02-2008 04:04 AM

Hmmm, I have been having intermittent problems on my 2000 S4 where the EPC and CEL come on and I can't accelerate past 2k rpm or so ( I doubt I could crawl over a speed bump in the parking lot its so bad). After I reset the ECU it runs fine. Is this similar to the symptoms you had for the brake switch?

BTW, what and where is the brake light switch? and does it throw a code?

**B5in** · 12-02-2008 08:14 AM

Originally Posted by ThirdROC

Hmmm, I have been having intermittent problems on my 2000 S4 where the EPC and CEL come on and I can't accelerate past 2k rpm or so ( I doubt I could crawl over a speed bump in the parking lot its so bad). After I reset the ECU it runs fine. Is this similar to the symptoms you had for the brake switch?

BTW, what and where is the brake light switch? and does it throw a code?

Mine didn't throw any codes & I have heard this happening to a lot of 2.7T cars, I would try there first since it's only $10-$15

brake light switch does a few things...

one circut cuts engine power when you stop and another circut controlls the brake lights. The switch has also been found to cause the three light syndrome you explained. It is a simple DIY and an inexpensive part.. the brake pedal swith in this image is on the right.

On a second note, this same 2nd circut from the switch that is causing your engine to "cut out" is also part of the Brake Throttle Lag (BTL) symptom most TIPTRONIC cars have.