mot failure

1. darklord Newbie Joined: May 2008 Posts: 16

   #1 6th January 2009, 09:03

   my car failed three mot's all on emmisions. by the third it had a new lambda and a new cat and only just got thru. what else can it be?
   
   might not have anything to do with it. but after i turn my car off the fuel pump makes it little noise. once or twice after.
   
   leaky injectors??
2. Ste Saxperience Post Whore Joined: Mar 2007 Yorkshire Posts: 5415 Saxo

   #2 6th January 2009, 11:18

   I dont think its the fuel pump, i think its ICV that makes the weard noise. Not 100% though.
   
   If you fitted a new cat, i think they take a few hundred miles to become fully efficient. And give your car a good hard drive before you MOT it again, when the CATs hot it gives better readings.
3. shaunyboy Frequent Poster Joined: Sep 2008 Manchester Posts: 538

   #3 6th January 2009, 18:34

   The noise is normally the ecu checking all the actuators, as for emissions when was it last serviced? Try some fuel system conditioner, new plugs, airfilter and an oil change. If it hasnt been done thats what should be done before changing any sensors or cat's. As said a cat wont be fully effective at 1st it needs to warm and cool a few times, also avoid hard driving for a few miles.
   
   Dont forget on the emissons screen where it says lambda it doesnt mean lambda sensor, lambda means air/fuel, so changes your air filter is shitty, it can also fail due to sports air filters, induction kits, k & n etc as your burning more fuel to compensate for the extra air.
4. melky2008 Infrequent Poster Joined: Jun 2008 grimsby Posts: 188 saxo vtr

   #4 29th January 2009, 19:00

   mine makes that noise its just the fuel pump priming again