# 2001 Vw Beetle codes Po455 and Po171??



## ultraman69 (Feb 17, 2006)

2001 Vw Beetle 65k miles. I thought I got rid of all codes and the car passed with clean emmision flying colors part of the smog check but it falied the monitors which had to be cut down to only 1 monitor so the attendant told me to drive the car on the freeway to activate the monitors. 
And he was right after driving 40 miles the monitors are active but now I have obd2 codes again. They are PO171 and PO455 with this codes and the check engine light on, this car will not pass the retest. It took one day to show this codes.
I'll try to change a new gas cap and see what happens. 
I am running out of ideas :banghead:, any help will be appreciated, thanks Joe


----------



## ultraman69 (Feb 17, 2006)

I have already changed a broken vacuum line, the O2 sensor, fuel pressure regulator, fuel filter, air filter. The maf sensor I cleaned it. Today I changed the gas cap, I didn't clear the codes because I am thinking that if I find the problem the computer will turn off the Check Engine light and I don't have to drive the car for at least 40 miles before the sensor monitors get activated!


----------



## billymade (Jan 29, 2008)

ross tech wiki: 

16555/P0171/000369 - Fuel Trim; Bank 1: System Too Lean

http://wiki.ross-tech.com/wiki/index.php/16555/P0171/000369

16839/P0455/001109 - EVAP System: Large Leak Detected

http://wiki.ross-tech.com/wiki/index.php/16839/P0455/001109


----------



## ODIS (May 1, 2012)

I wouldn't expect the trouble codes to clear themselves even if you fix the problem. Even if the check engine light goes off somehow, there will still be intermittent codes in there that will cause you to fail inspection.

What engine do you have in it?


----------



## ultraman69 (Feb 17, 2006)

You are right. I had to erase the codes with my Obd2 scanner, I changed a good Maf sensor and after driving more than 50 miles the Cel turned on and now I only have PO455 evap code. I have to check my Evap system for leaks. My engine is a 2.0!! Thanks for replying.


----------

