Hi, my Dads car failed the nct with high emissions. The mechanic that I brought the car to changed the lambda sensor, and MAF and the car failed the retest.

 

I took the car back to him, he had another look, and said that the throttle body was loose, and that the purge valve was faulty. He tightened the throttle body, and said drive the s*** outta her for a week and then get her tested.

 

I brought the car back to him thinking he was gonna test the emissions, but he doesn't have any emissions testing equipment lol He said bring it to a DOE centre and they would do the test for €20. I said what would be the point if the purge valve is faulty, he got thick, and accused me of messing him around!

 

Anyway, I doubt it, but can a car pass an emissions test with a faulty purge valve??

Purge valve? You mean the EVAP valve on the charcoal canistor?

 

If that valve gets stuck open, it basically introduces an air leak into the inlet system. Pull the pipe off between the valve and the inlet manifold, and block it off at the manifold end. 

Yep that's the one, the EVAP valve.  I'll try that and hopefully she'll pass!