I have a 97 wrx and has just failed mot on co emissions. Has got 1st cat but not 2nd. Only done 3000 miles since last mot and passed with no problems last time. I have only replaced lamba sensor as this came up on cel but not come on since change. Does anyone know if the readings are different for an import?or what the reading should be? and has anyone any idea what i can do to sort this???

Cheers
Mark

 

Im not sure if this is the same problem but my 2004WRX only has one sports cat in the exhaust and has trouble passing the emissions unless its really warm ie take the car for a good blast then test it straight after.. Cats work better when they're hot so ive been told. Im no expert mind so hope this helps..

 

Was the cat very hot when emissions were checked? What readings did you get? Having the readings may helo idendify the issue

 

fast idle test co reading was max limit was 0.300, failed reading was 0.678. Second fastidle test read 0.640. Passed on everything else. Wouldn't say cat was hot but don't think it was cold as was tested quiet soon after i arrived (test place bout 30 min drive away).

 

Hi m8 I had my 95 Sti mot 4 years a go wive no cat and was ok the larst year I had to put a cat on and it just past m8 it had to be hot I went for 50 min run and that do it for me m8