My 2002 Jeep Cherokee 3.7lt drinks fuel like a camel at an Oasis!

[lloyd4560]

Hi,
My latest acquisition, a 2002 Cherokee V6 4x4 with 208K on the clock, just 'guzzles' fuel by the liter.
I'm getting under 6km/lt - suburban driving (Gold Coast)!
I've done the following to the motor:
1). New spark plugs (Champion) installed - the old NGKs were amazingly a 'Textbook' look, burnt light brown, no oil, no soot, gap looked good.
2). New air cleaner filter installed.
3). I'm using the O/D feature when not in 'bumper to bumper' traffic ( Gold Coast).
4). I've replaced both Cam and Crank sensors - (DTC codes came up).
5). I use E10 often and 95 Octane when it's not a 'rip off'.
Something has to be wrong with this 'lemon' - O2 sensors and MAP not sending signals to the PCM perhaps.....?
Imagine the consumption off-road and on a soft beach .... oouch!
Anyone running on LPG as a possible solution?
Guys, if you've suffered the same fate and have a fix, any ideas and advice will be greatly appreciated.
P.S. I'm also struggling to understand how to navigate around this great site - any pointers please. Thanks guys!

[Alexski]

Hi 6km/l is 16.6l/100km
This is pretty High but i will say my experience is not that much better. I think they are advertised as 14.5l/100 around town, I would get around 15.5l/100 in heavy traffic or 14.5 in mixed urban/freeway commute.
My economy dropped noticeably after i swapped the standard 16in rims and tyres to the limited editions 18in with stock tyres. Interestingly they do not have same rolling diameter the 18's are around 1cm taller. With the 16's I used to get 13.5l/100 in mixed driving. So tyres make a big difference.
Even on long freeway run the best i get is about 11l/100 cruising at 115kph.

As a comparison my 4.7l V8 WJ Grand would drop into the 9's on freeway run and get around 12l/100 on my commute.

If I was you O2 sensors are the most important thing to change. They last about 100000mile or 160000km before they need changing. Most important are the Precatalyst sensors these directly affect fuel air ratio, as they deteriorate they tend to make the engine run richer. They won't necessarily throw an engine code either most common symptom is poor fuel consumption.