changoo

My ESP light has been coming on after I drive my '02 A4 3.0 for about 10 min. If I shut the car off, the light turns off but sometimes comes on after driving again for a little while. I heard this could be a dirty or bad MAF sensor...if so, does anyone know how to get to it? Also, could it be a different issue?

Thanks!

lyleswk

First comment is I am assuming this is coming on all the time, not during extreme manuevering or slick conditions. This would be normal during this sort of driving.

That aside, ESP (triangle with exclamation point) is not related to MAF. MAF would cause rich / lean running issues and turn on you CEL / MIL (little engine light). ESP light is generally associated with wheel speed sensor or yaw sensors. Need to download codes via VAGCOM (don't beleive generic code reader will work) and find out what is throwing the code.

namjachoi

had this exact issue. went to check it today they said it was a faulty brake switch. part was 19 bucks audi dealer tried to bill me 200 for labor.

xsrfsno225x

Do you mean EPC light? Does the car restrict itself? If so MAF can cause this. If MAF is bad the car will think it's overboosting.

lyleswk

I quite honestly do not really understand what the EPC (Electronic Power Control) reflects. It always seems to be redundant to the ABS or CEL lights. OP said ESP, so was going based on that.

xsrfsno225x

Is the car restricting itself? Like you hit the gas and it bogs down??

I've had a bad MAF making it think it was exceeding torque limit so it would restrict itself (that's why i asked) Vag-com it and look at MAF reading

sinful7

Just for reference, I have seen an intermittent ESP (Triangle/exclamation point) light come on recently. Coincidentally, I had my car checked out for a general physical and the VAG codes that came back for the ESP are:

Brake Light Switch, Implausible signal;
Yaw Rate Sensor G202 Reference wire electric circuit failure intermittent

I'm gonna throw a brake light switch in there before I even look at the yaw rate sensor. The former is $9 from ECS and the latter is

sinful7

^^^ Edit: The latter is $650ish. So one, then the other. ;-)

Ritz

Before you replace it, I believe there's a method for recalibrating it that involves driving in a tight circle at a specified speed range. I think I found the procedure on Ross-tech's site when I needed it for my A6.

namjachoi

replacing the brake light switch worked for me. good luck!