MOT failure

[Sheff's Cordy]

My cordoba failed miserably on emissions amongst other small things. The MOT tester said the cat back system and a pipercross filter caused it to fail. They cant make that much differance can they.

 

[aminspace]

Hi, mine's just failed on the same thing - not much help probably, but here's my results,

Fast Idle -

CO: 8.573
HC: 1006
Lambda: 0.746

2nd Fast Idle -

CO: 8.074
HC: 788
Lambda: 0.767

Natural Idle -

CO: 7.495

The garage seemed to think it was two issues - burning oil, and too rich a mixture. They couldn't/didn't want to suggest anything in particular that was causing it.

I've rung a local VW guy to ask about a diagnostic - describing it over the phone, he suspected it may be a lambda sensor issue (something I was wondering about, too). The other alternative, I thought, was a CAT/exhaust problem. I'm certainly no expert, but would've thought that they *would* make a big difference, if they were seriously faulty?

(There was blue smoke *everywhere* when I turned up to collect my car - he was still in the middle of the 2nd fast idle test. I was pretty shocked, I have to say, obviously I don't do that to the car during normal use, so I'd never seen it do that. I thought something was on fire when I first got there.)

eta - It's a 1.6 T reg Vario.

 

[martin_hill_198]

for readings of tyhat hight engine might be badly damaged if loads of blue smoke all i can say is try a lambda sensor and drai oil till on the minimum mark and a new car .. had to do this to mine

 

[aminspace]

Did you mean car, or cat?

TBH at this stage, if the engine's that badly damaged I'm starting to think a new car might be a good idea.

 

[jezzag60]

Probably just something simple like a temp sensor or a lambda. The CO is so high that its not just a cat problem..... although the cat may well be damaged if its been running like that for a while!

 

[aminspace]

Probably just something simple like a temp sensor or a lambda. The CO is so high that its not just a cat problem..... although the cat may well be damaged if its been running like that for a while!

Thanks - took it to someone and got a diagnostic yesterday, and the lambda's had it, so I've got one on order at the local motor factors for monday. (Diagnostic guy seemed to think the cat should be ok.)

The other thing that the first garage I rang mentioned, with regards to the blue smoke/oil issue, were engine treatments - anyone got any thoughts on that? I've got till Thursday next week to run it back in for its retest, so I'm obviously limited to how much I can do between now and then.

 

[aminspace]

Quick update - it passed! Failed the first fast idle test, but the tester guy gave it a few good revs, blew a load of soot out the back, all the numbers went crazy for a moment then it all settled down and all was good.

New lambda sensor seemed to do the trick - there's obviously still an issue with one of the cylinders (one of the spark plugs oils up on a regular basis), but where there's life, etc.

 

[Sheff's Cordy]

finally passed took it to a better tester the lambda was at fault nothing to do with the induction kit etc now its running sweet again. I have that issue with oily plugs but it only builds up round the thread.