Running Lean

[JonnyB 1]

My standard 1.9 gti passed its MOT yesterday but it was running very lean:

 

CO % vol: 0.227 (max 3.5)

HC ppm vol: 282 (max 1200)

 

Any ideas?

 

 

 

Thanks

 

J

[j_turnell 137 3 Cars]

Get it back on the analyser and turn the allen key slot on the afm clockwise to ritchen it up, personally i set them to around 2.00 CO then just adjust the idle when warm.

 

The hydrocarbons is spot on so wouldnt worry about that.

[Rom 0]

I think the 8v is the same as the 16v, in that you can only just the idle CO. Which is what that reading is.

 

As said though, theres a screw in the AFM. Needs to be on the analyser when your doing this though really, so you can measure any change.

 

My Mi was around 4.5 when i first put it in

[JonnyB 1]

Thanks for the advice

 

The emmissions were OK last year so suspected there was a problem - blocked injectors, poor fuel pressure, or afm on the way out.

 

MOT tester did not want to touch the car though- suggested a rolling road..