VN problematic oxygen sensor??????

[vn3.8L]

Hey,
my vn is getting ready for a road worthy, however I had an engine warning lamp come on, checked codes, it was number 13, so i replaced the oxygen sensor.
Since then i haven't driven it however it was about 3-4 months ago and i have started it 4-5 times just to warm it up.
I don't really rev it i just let it idle everytime i start it i reset the system by connecting my battery. Today just reving it at probably 1600-2000, the engine warning lamp flashed, so i checked for codes and again it was number 13.

Does anybody know why this is happening could it be that the fuel has been sitting in the tank for 5 months?

I also pulled the oxy sensor out and it looks like brand new, this problem needs to be fixed?

Thankyou

[Not_An_Abba_Fan]

The O2 sensor doesn't work until it reaches about 250 deg C, just idling and warming the engine up won't make the O2 sensor read correctly. The ECU will look for a signal because the engine has reached the correct temperature, but the sensor will not output the correct voltage because it is still cold. You will need to take it for a drive for the O2 sensor to start working. Don't worry about the code, just clear it when you are ready to drive it.

[vn3.8L]

Great, thanks for that I will clear it give it a drive and let you no how it goes

[vn3.8L]

Oh and also today, before I read your post I changed the cpu because I had a spare one from my brothers s pac, to see if it would make any difference.
Do you know if there are any differences between the cpu's, chips in the s PAC and in the executive.
Looking around they have the same codes but some people have reported that there cars have felt much quicker with an S PAC memcal.

Or is this just people dreaming?

cheers

[Not_An_Abba_Fan]

Placebo effect. If the serial numbers are the same, then they are the same. I bet if you told someone that you just changed the memcal to an S Pac one, they will think it feels faster.

[vn3.8L]

Yeh thats what i thought it would also be as well, all well It only took me 20 seconds to change the cpu, and it wasn't all a waste of time because behind the cpu there was a wire for the door open close switch that had been warn through and was in direct contact with the cpu.
Also i have noticed that my vn cranks over very slowly, the battery seems to be fine though, any suggestions, or are the VN's normally turn over slow, the oil i am using is 20w-50 versus the recommended 15w-40, next week i will be putting 15w-60 hpr 15 penrite oil in it, just because i think some of the top end rattle noises that the engine made when cold start up were due to running slightly thicker oil. It was not making these noises before.
But I don't think running slightly thicker oil would make a change at all to the speed in which the engine cranks over.

Should i clean the earth connection to minimise resistance. Also just for the sake of it I will be changing my battery as my Dad has a spare brand new one.

Thanks