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Dwayne Dibbley

MOT fail - lambda outside specified limits?

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Ca has been for her first MOT and failed with Exhaust lambda reading after 2nd fast idle outside specified limits, car has the resonator delete and a VWR CAI  can any of these cause the high reading?

 

Fast Idle Test Lambda 1.066

Second Fast Idle Test 1.070

 

limits are supposedly 0.970 - 1.030 ? 

 

the tester tried four different engine codes but none of them gave a passable reading.

 

could sticking the standard air box back on be worth a shot? cant see the resonator delete effecting emissions.

 

Thanks

 

 

 

 

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12 minutes ago, Dwayne Dibbley said:

Ca has been for her first MOT and failed with Exhaust lambda reading after 2nd fast idle outside specified limits, car has the resonator delete and a VWR CAI  can any of these cause the high reading?

 

Fast Idle Test Lambda 1.066

Second Fast Idle Test 1.070

 

limits are supposedly 0.970 - 1.030 ? 

 

the tester tried four different engine codes but none of them gave a passable reading.

 

could sticking the standard air box back on be worth a shot? cant see the resonator delete effecting emissions.

 

Thanks

 

 

 

 

No reason that should fail, is it deffinitely catted?

 

Anyone else think the cat may have gone bad?

 

If its first mot did you have 3 years warranty, if so I know it would be out side the 3 years but i would challenge it with vw maybe...

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Yep still original cats, just the above intake and resonator cut outs.

 

Sill in its 3 years by about 3 weeks, but as the exhaust and intake altered they may not support a warranty claim.

 

I can refit the original air box and rerun as its only 0.04 out? 

 

Thanks

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My argument would be that the resonator doesn't affect the cat, all it does it resonate the noise.

 

If you had engine issues and a decat, then yes they're more likely to send you on your way

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I have the r600 and res delete no problems passing emissions for me you could try a can of cataclean run that through and get it good and

 

hot before you book it back in for retest

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Certain items are covered longer with a separate emissions warranty (at least here in the US) with up to 8 years and 80,000 miles (look in your booklet)

 

It may be worth putting the CAI back to stock and having the dealership take a look at it. Agree that the res delete should have no impact at all.

 

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Like what @tuono said, make sure the test is done when hot (oil up to running temps) as this is when the cat is most effective. See their print out for the failed test to see if it states oil temp at time of test...

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9 minutes ago, Count Drunkula said:

Have your spark plugs ever been changed?

 

I had a car fail on emissions a few years ago after repeated attempts and the CAT very hot.

 

Problem was coked up plugs causing incomplete combustion within the cylinder

 

Not that i know of? is it easy to see by pulling them out visually?

 

Thanks

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44 minutes ago, Dwayne Dibbley said:

 

Not that i know of? is it easy to see by pulling them out visually?

 

Thanks

Yes, if you havent done it before, get someone to check for you i.e the garage. Replacement plugs are inexpensive

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16 minutes ago, Dan1982 said:

My car was the same and was blowing and leaking around the res delete also As strange as it sounds get them to try the probe in one of the other tail pipes

 

so can blowing / leaking cause the high reading? i guess you fixed the blowing and all was OK?

 

Thanks

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