Tintop failed MOT on emissions

[robp]

Had the wife's Freelander in for a MOT this morning.  Failed on the emissions.  Passed everything else which was good but I need to get it sorted.  Just after some advice about possible causes.

The motor failed on emissions last year too.  The honeycomb in the CAT was crumbling so I replaced it.  I decided to get a cheap CAT.  As the motor is pre 2001 I didn't need a type-approved one.  Many people feel the cheapo one are a waste of money.  Probably right but it did get through the car through the test OK afterwards.

Today, failed on CO; nearly double what it should be.  Fine on HC and lambda.  Could be CAT again but the high CO maybe down to a dodgy oxygen sensor - the ecu will widen up the injector pulse till its very rich.  Engine itself runs sweetly and ticks over like a sewing machine.

Anyone any advice?

[bluehornetrider]

Might be the engine is a bit coked up and a good treatment and blow all the soot out will be good enough to lower the emissions.

[fullpint]

Try a seconhand lambor sensor or another MOT garage who may well pass it if you drop a 20 quid note on the floor

[robp]

Well, put a new CAT in the Landy.  I got a better quality one this time.  Took it back for a re-test and, bingo, flew through.

CO pass: <0.3%
CO before: 0.63%
CO after: 0.03%

So that's SWMBO's motor sorted for another year. 
Now it's time to get a MOT on the Westfield.

who may well pass it if you drop a 20 quid note on the floor

Love it!  Got to be worth a try! 

['The Gaffer']

Result Rob

Take the Westy to FCM - Club discount there and very sensible MOT.

[Moleman]

I have a feeling the westy will do fine. 

[robp]

I have a feeling the westy will do fine. 

You were right, Colin.  Westfield passed MOT today with no advisories!  Great day for a spin too; nice and sunny, dry roads.  Bit cold but the engine likes that.

That's two motors though a MOT this week. 

[Moleman]

Nice one.