P0421 and P0431

[Massa in Perth]

Hi guys, my QP5 threw the above codes this week, no idea why, car is running normally. I had been driving for maybe 15 minutes.

Puzzled, I checked for info on the forum and found the below thread which closely mirrors my experience. Nothing in the QP forum though. The OP hasn't been active since 2015 so no chance of asking him whether he got to the bottom of it or not.

http://www.sportsmaserati.com/showt...up-catalilyst-codes-CEL-codes?highlight=p0431

I reset the codes and have driven maybe 50kms since, no codes. I will be taking the car to my mechanic soon as it's almost time for its service anyway, but I thought I would check with others whether they've seen and diagnosed the cause of this fault?

Car is only ever filled with BP Ultimate 98 unleaded and nothing else has changed, so it's out of the blue.

Many thanks, Toby

 

[alfatwo]

A lot of these problems are due to low battery voltage on start up,.. I know they start just fine, but if any of the cars ECU's sense low battery voltage they'll throw up fault codes!

Dave

 

[CatmanV2]

I doubt it's the case here, but as ever I will bow to the experts.

Quick googling seems to indicate that either the lambda sensors is failing
or
There's something wrong with the cat
or
there's an exhaust leak (02 too high)
or
Your secondary air system isn't being effective.

I'm sure Voicey can explain why I'm wrong (if I am) or what else could be wrong, but in absence of any more expert input, I'd be checking the lambda sensor connections and then getting it on a diagnostic to see if it's behaving properly.

C