Thread: D2 V8 fuel consumption

There's nothing you can really alter to effect the tune. The only option is to replace the ECU with a reprogrammed unit from the UK.

is there definitive test to know if ECU is stuffed, and is this the mileage frame they usually kark it at?

ECU's either work or they don't. They don't really degrade and effect consumption. 20L/100Km is pretty ave for a V8 2.5T brick. I'm currently getting about 330km from a tank in mine but there's a couple of issues to sort out plus a reprogrammed ECU coming from the UK to better suit the 4.6.

if O2 sensors were sick before, and engine running 'lean', might that have got me my somewhat abnormally good initial economy?

during my 11,000 km around NT and WA, i found, my fuel consumption varied between 12l/100 and 20l/100.

best was 12 while doing 70km/h on the blacktop (and worried about running out of fuel, 5l left)
worst was 20 while doing 140/h on the blacktop
average on black was 16
average off the black was also 16. i attribute this to lower average speed.

They run very lean as is.

The (long) shorthand version is, MAF measures air (as a product of it's mass) entering the engine, ambient temp and pressure are also a consideration of the equation created by the ECU to effect an absolute combustion each cycle. Timing, knock and other inputs are also added. The O2 sensors see how much unburnt O2 comes through the exhaust and adjusts the cycle to create a more complete burn

A failing MAF will give symptoms of missing air mass entering the engine so the ECU hears "no air" so goes "oh well, don't add fuel" but the O2 sensors scream "too much unburnt O2" ECU says "add fuel". Transmission says "screw you guys, I'm going limp until you work your differences out"

Failing O2 sensors will not see any unburnt O2 and so will allow the ECU to lean out the cycle until knock it detected plus other stuff.

The short version is air and petrol goes in, it gets set fire to and goes bang. Repeat.

I shouldn't try to explain after most of a bottle of Gin.

New cars have no soul. Except Land Rovers.

If we wanted economy we'd be driving Corolla's.

Oddly enough I am at the moment due to incompetence. Can manage 8L/100Km in city, 6.4 highway.

But it ain't no Rover.

got 18.8 L per 100km this time. Coming down, might put some injector cleaner in. Wonder if the O2 sensors are good enough (they werent the super cheap ones but they werent overly dear either)
Im sure I used to be comfortable getting close to 500km a tank but now getting worried after 400km (dont want to drive it to the light; the fear of fuel pump failure makes me want to keep tank nicely topped up so no crap gets in to pump lol)