When to change gear and revving.....
 

I have a 2004 Uk 231 31000

Having trouble to engine light recently. Had a P0172 code 4th april and they changed the 02 sensor for £170 uk pounds, almost $200 dollars.

Three weeks later, same code and engine warning light that comes and goes. Says its an open loop Bank 1 sensor problem

Took it back to Mazda, who are useless, and told me that the car isnt driven at high enough revs to keep the sensor from malfunctioning. most of the driving is around London Uk, so stuck in traffic.

When are we supposed to change gears from 1 up til 5? I have been around 4 to 5 thousand on the motorway but probably less in town

Is this true that I need to be revving it to 8000rpm daily?

What are other people out there doing? Am I driving it wrong?

Help and suggestions would be much appreciated

I'll be honest and I might get flamed for it, but I don't believe that what your dealer told you is true...

I drive my 8 pretty much all the time below 3K, usually shifting at 2K for all gears. Now, given that mine is a 4AT (I know not cool lol), and yours has 6 gears, I don't think that would make much of a difference.

Besides the low rpm driving, I do of course compensate with 'spirited' sessions of drifting attempts and high revving 'cause I love the sound. Especially with my intake mod, it's a bit louder so it sounds nice. :)

Now on the revving, to 8K daily, I don't think is necessary, but like is repeated so many times on the forum, high revving is healthy for Rene. After all, revving while standing still doesn't really do much, I think the engine has to be under load to contribute to the fight against carbon.

Now just for clarification, P0172 is code for a rich run, correct? If that's true then I guess the easiest thing to start with, is to try cleaning the Mass air-flow sensor (MAF) and the sensor that is integrated with the MAF, the little brownish-yellow bulby looking thing, (IAT???); and check your spark plugs to see if the richness is fouling 'em up. I know that if the IAT is dirty or messed up, the car won't register correct idling temp, and so won't correctly idle, and so won't correctly compensate with richness/leanness of the air-fuel mixture.

You could also do a seafoam cleaning to get whatever might be stuck in the combustion chambers out, but definitely check the two sensors.

There is a reason we say "A redline a day, keeps the carbon away." These engines were made to be driven hard intermittently. Get out on the A1 and clean it out.

Hitting the red. A fair amount. Usually 2 or 3 times in a row. Remember that you don't HAVE to SPEED to redline. It is around 40ish in 1st.

It is true that you should take advantage of the wide rpm band often to reduce carbon build up but unfortunately it is also true that having 3 water leaks and mazda blaming you for that sucks.
Did they solve the problem eventually?
Where in London are you?

WOT to 8500 rpm a few times per week after warmed up

lol, oh yeah, rev AFTER warm up... not when it's still cold... lol ^^'