Lagamorph

iTrader: (12)

Had a very sedate drive to Hereford today and my check engine light came on. Data monitor told me it was P0420 which is catalyst below threshold I believe. I thought this should have been mapped out by my mapper?

Reset for journey home and all was fine again but.......

I also had P0734 which is incorrect ratio for gear 4 in historic fault codes. Should I be worried by this?

Adam-M

Would it not be best to ask your mapper?

Lagamorph

iTrader: (12)

Its not something I would bother a mapper with on a sunday (probably his only day off) and im curious about it now as its my daily drive so wouldnt want to put unecassary miles on it monday morning if its best I didnt use it at all. Someone may have given me a useful reply today if they could find the time to do so and if not then yes I will contact my mapper during the working week.

bluenose172

iTrader: (2)

Do you have a full decat?

Lagamorph

iTrader: (12)

Full decat and mapped to suit.

bluenose172

iTrader: (2)

...then the mapper has forgotten to remove the CEL in the map. Phone him and ask him to remove it for you.

jura11

iTrader: (7)

This P0420 sometimes can show afterwards mapping or after few days,but usually speak to mapper which can have look and can mapped out this without the charges

If persist after mapping would say,your Lambda is going out and probably is faulty

P0734 is as you are said,Gear 4 Incorrect Ratio,which can be low fluid in the diff/gearbox etc or something else I would speak again to your mapper,but if its historic this means is not present and i wouldn't be worried so much,but I would this investigate

Jura

JonMc

iTrader: (51)

I've had P0420 come on even after the fault codes had been disabled and this was witnessed twice by myself, first during the mapping and secondly during the check. If you know it's been mapped out reset it and carry on, the second CAT is a check reading that confirms CAT efficiency

Lagamorph

iTrader: (12)

Cheers guys. Had visions of my gearbox eating itself