Yet another MOT failure....emissions:(

[Adam fc]

Hi all, Ive recently had my fc3s turbo 2 put through an mot to find out \'surprise surprise\' the emission\'s were way off!

 

Ive recently installed a front mount intercooler and new fuel pump along with all the filters and a new set of plugs with magnacor leads. I allso swapped the after market ecu out for the standard one hoping it wouldnt run so rich in preperation for the mot.

From the results it seems its running rich and isnt burning the fuel and its hunting like it has an air leak which i was half expecting from fitting a front mount intercooler as theres plenty of chances for air leaks on the new connections.

Im guessing this issue is a collective of of problems rather than an single  fault?

If anyone has any info or knowlage please share as i dont know where to start:( cheers Adam

[gibby250983]

Lamda sensor..........try that bud!!!! i had the same problem a few years ago........found out that it wasnt the lamda sensor it was a hole in a pipe!!!! too much CO2......when ya rev it up on the mot ya would of found that there was too much CO2 and the Fail would o been a pass!!!!

Try the sensor first bud!!!

[Prof]

Lambda sensor does nothing for idle emissions on rotaries - it\'s only used for cruise and light load and only actually doing anything between about 1500 and 3000 rpm.
 
With that out of the way - the figures you\'ve got suggest the airpump is still on - as your CO figure is pretty low
 
The High HydroCarbons (HC) reading is almost certainly down to too rich a mix on idle.
 
Could be :
 

• Air leak
• Old or fouled plugs
• Engine not warm, or sensors not picking up that it is - the water temp sensor on the back of the water pump is the one to check.
• Too High a fuel pressure on warm idle (quite common after a fuel pump replacement such as Walbro)
• Ignition timing off

He\'s done the no cat test which is correct.  At the discretion of the tester, they can increase the rev\'s to see if the HC reading lowers, provided the CO reading is low.  Doesn\'t look like he\'s given you the benefit of that test.
 
I\'d suggest sorting out any air leaks first - and check timing - maybe pull the plugs and clean them or try a new set in there.
 
For the fuel pressure problem - depends on what pump you\'ve put in there and what other mods you\'ve done for fuelling.