Smell of fumes inside car?

[stallard2014]

Hi guys last few weeks I can smell what smells like exhaust fumes, in side the car when driving. Only thing is its not all the time mostly when I've been driving for a while and when engine is hot.

Also engine management light on code P0420 Catalyst efficiency Below Threshold Bank 1

If there was a leak from the exhaust system, wouldn't the smell be there all the time?

Any ideas is it just the CAT that's the problem what do you guys think?

Plus how much for a new CAT?

Thanks for any help guys.

112000 miles.

1.6 T Spirit 2002 petrol

 

[oldcodger]

Hi,

You really need to get the exhaust inspected very soon, you could knock yourself out etc !

Also hints you might have poor seals around the doors etc to let the fumes in, you have closed all the air vents etc  in case its coming from the engine bay ?

While many web sites seem to say P0420 is the CAT , my code readers book says it would  be the front and / or rear oxygen sensors,  coolant temp sensor,  leaking exhaust manifold / pipe or the Cat.

Think getting the exhaust leak sorted first,  a garage ramp job really,  unless you have some driveway ramps at home.

Then  clear the error codes, assuming you have a code reader, or a garage can do that , then see if the error returns.

[Notoyboy]

I'd re-inforce Oldcodger's suggestion to check/sort the exhaust first.  I suggest first thing is a thorough visual check of the exhaust.

[stallard2014]

Thanks guys booked in to check exhaust..

[roks]

My p0420 was fixed by changing both the o2 sensors.