BojanA6

Hi guys. I'm new to these forums and stuff and I'm foreign so pardon in advance if I misspell something.

I have an Audi A6 C5 (2002), 3.0L V6 30V Quattro with 218HP (160KW) and I'm having a HUGE loss in power in the last few days.

The car starts fine, it runs great in idle, everything's OK untill I floor the pedal and it just gives me EPC fault on the dashboard and another fault which is, I do believe, for the ESP. I added the attachment of the ESP fault (note it isn't the original photo of my dashboard). So, when I floor the pedal, it gives me the faults and I just can't get above 2500 RPM. It just stays there, no matter how much I floor the pedal. It happens in every gear, doesn't matter if the enigne is cold or warm. Everytime I floor the pedal it gives me the faults and it just won't get past 2500 RPM. So I have to shift it before 2500RPM and I'm driving like a grandpa.

Naturally, I didn't want to **** around the car so I went to see a few mechanics and all of them gave me DIFFERENT reasons for the problem: Lambda Sonda, ESP sensor, fuel pump...

The problem is, I'm not so good with money at the moment so I'm not willing to just take a guess and pay one mechanic to ''give it a try'' with one solution. So, ANY ideas on what do you think it is would be much appreciated. Especially if you had the same problem as me.

jcman

"EPC" is an abbreviation for Electronic Power Control and refers to the electronic throttle control system.
When the ignition is switched on, the engine control module checks all the components of importance to the electronic throttle system.
After switching on the ignition the engine control module switches on the EPC warning lamp.
The EPC lamp goes out shortly after starting the engine if, on the one hand, the engine control module does not detect any malfunctions in the EPC system, and, if activation of the lamp by the engine control module is OK.
If a malfunction is detected in the electronic throttle system while the engine is running, the engine control module switches on the EPC warning lamp. (These DTCs are listed in the DTC table). At the same time, an entry is made in the engine control module DTC memory.

So at this point you have been told just about everything but the real source of the problem, you really need to see what the DTC's are "Error Codes" with vagcom to begin proper diagnosis.

jcman

Let me make my point clearer.

Get vagcom or find a mechanic with vagcom who knows how to use it.

Good Luck!

BojanA6

The EPC does come on when I start the ignition and it goes off when I start the engine. And I'm having no faults, car works fine, but whenever I give it some gas/floor the pedal it instantly turns on the faults and I can't get above 2500RPM. And it resets after I turn the engine off but the next time I floor the pedal it's all the same.

All of the mechanics I went to have some type of diagnostic program, and all of them told me different types of faults in my car. Seems to me that the mechanics in my town just aren't up to the job and I'm afraid I'll have to go to the official Audi dealership and I'm sure they'll leave me skinned with their prices but it looks like I don't have a choice here.

Do you think there is a slight chance of the problem being in the throttle body? I'll try cleaning it tomorrow. Will keep you posted.

jcman

A VW service center use's the same diagnostic protocol be it a dealer or an independent.

Find your problem before you make more of one.

jseklund

Codes would be very, very helpful. Without them, I am just making complete, blind, wild guesses.

Some things to check: Check your Mass Air Flow sensor - is it unplugged? Is it somehow disconnected?

Check for boost leaks. Are all the pipes connected and clamped down?

Any check engine light? Solid or flashing?

The diagnostics tool would be very helpful. VW/Audi will probably charge $80-100 just to read the codes. You can buy a Vag-Com for about $300 and be done relying on them for diagnostics...

jcman

I agree with your advise but the 3.0 don't sport turbos.

BojanA6

Thanks for the tips guys but I don't have a turbo on my Audi and I'll check to see the MAF sensor if it's unplugged or damaged. I'll give that a try and also try cleaning the throttle body.

Right now my best guess is that my ESP sensor is dead/damaged. Will give those 3 options a try and if all fails I'll just have to trust the mechanics in my town.

Thanks for your help guys, I know that without the codes we're all making blind guesses but I don't have the diagnostic tool and I thought maybe some of you had similar problems with your Audis. Thanks for the help.

Will keep you updated as soon as I fix it.

jcman

There is no one main ESP sensor, ESP is "Electronic Stability Program" that reacts to the inputs from all wheel sensors, engine speed and steering angle to act as a higher level traction traction control independently pecking at one or more wheels to achieve traction using EDL "electronic differential locking" and controlling engine speed to correct driving control.

So just remember ABS, EDL and ESP all are similar functions from the ABS controller.

If you had a bad wheel sensor, abs module fault or relative problems you would see a brake/abs warning light in the dash cluster.

It is very logical that the ESP light is on because of the EPC problem you have therefore not allowing ESP to function, one fault can lead to others right down the line.

Please take my advice and have the car properly diagnosed with the right tools, we could only speculate what is going on without DTC codes so again get to the bottom of the EPC problem first or post the codes so we something to go on.

BojanA6

I'm not sure it's called ESP sensor but I'm talking about this thing (attachment).

I'm pretty sure it has something to do with ESP, there's a problem with it and it won't let my engine run past 2500 RPM. Again, we're all just guessing here.

As soon as I fix the problem, and I sure hope it will be soon, I will let you know what was causing the problem.

Thanks for your time man.