Newbie

[kingyfisher]

Hi to all. Newbie here Need lots of help. New Navara STX550 Silver. Blue Mountains Australia.
Alloy bar 130 litre long range tank. need help about trip computer recognising big tank ??
Thanks
Kingyfisher

 

[KraftyPg]

Welcome Kingyfisher

I don't know exactly how the Nissan Diag stuff reads the tank size but my guess is there is a setting somewhere in the setup. I doubt Nissan would have been naive enough to make it one size fits all because the portion of the ECU that produces that information wouldn't be Nav only. Did you get any documentation with the trip computer?

 

[scottybobcat]

welcome to the forum

 

[kingyfisher]

Thanks,
But no doco - Yet will chase up and let you know outcome.
One day reads 550klms left to go , next day 683, next 599 ? Will see what happens as I drain it. ??
Kingyfisher

 

[Old.Tony]

Welcome to the forum!

Can't help you with the larger tank issue yet - the 550 is still a bit new and I don't have one to play with.

Larger tanks have given a fair bit of grief because the level senders don't always register properly - sometimes they won't show any fuel being used until they're like half empty.

Won't be long and I'll have one myself, but not having a 550 I still won't be able to help. All I could suggest is seeking the documentation, or finding someone in a Nissan service department that could give you the info.

I bet there's a few others here that could use that info too.

 

[kingyfisher]

Welcome Kingyfisher

I don't know exactly how the Nissan Diag stuff reads the tank size but my guess is there is a setting somewhere in the setup. I doubt Nissan would have been naive enough to make it one size fits all because the portion of the ECU that produces that information wouldn't be Nav only. Did you get any documentation with the trip computer?

No doco's but every day the thing re-calculates the number of klms left to go. when the needle finally comes off full it appears to catch up. will just monitor it and see what happens. Litres per 100 klms seems to work ok . varies between 9.4 on trip and 10 in traffic.
Kingyfisher

 

[KraftyPg]

LPH will be read from the ECU not the tank so that should be as accurate as any trip computer but the tank data resetting obviously means the ECU can't read the tank size. If there is no docos I think your only choice is to take it back to Nissan and ask for some docos, if your local dealer wont help find a new dealer because there has to be docos somewhere for the system.

 

[Old.Tony]

I was watching my ECU's output, specifically looking at fuel rail pressure, fuel flow rate and LPHK. It seems to be directly in tune with the loud pedal position, vehicle speed and engine load.

My guess is that the ECU knows quite well how much fuel is squeezed through those injectors at a given pressure for a given period of time, so once it knows how fast you're moving it's just simple maths to arrive at the LPHK figure. Deviating from standard tyre sizes will provide incorrect inputs to the ECU which of course then provides incorrect outputs, of which I am guilty.

I was in ARB yesterday afternoon booking my car in for a Long Ranger auxiliary tank and the guy suggested that the auxiliary tank empties into the main tank first, then the main tank starts to empty and the fuel gauge begins to display as it normally would. I guess I'll get used to that.

 

[LLadnar]

Welcome to the forum n have fun