The 2003 Landrover Discovery II V8 (4 liters) used an excessive amount of fuel, but there were no fuel leaks anywhere and the fuel gauge reads correctly … what needs to be done next is to read the trouble code with an LR-specific diagnostic scanner such as the Foxwell NT510 and what was happening. know. over.
Car model and year: 2003 Landrover Discovery II V8 (4 liter)
Symptom:
Using excessive amounts of fuel
Nowhere is fuel leaking and the fuel gauge reads correctly… not driving differently, no noticeable fuel smelling exhaust or anything else.
What to do next and the possible cause
Definitely check trouble codes with a LR-specific diagnostic tester.
Drive your Disco without the MAF cable connector connected. If the problem remains the same, it usually means a bad MAF sensor.
Update:
ok… just arrived from the garage… everything is being checked and no code… trim is good… oxy sensors are good… .tps good… coolant sensor – good… start or blown% $ d – no vacuum leak detected…. MAF is clean ……. clean air filter – oil free type …… no fuel smell from exhaust… no fuel leak…. It runs 98 octane fuel as usual… ..
the mechanic is thinking about replacing the MAF (would have done at least 100k + km) anyway to see what happens… and also the evap drain valve as this could cause problems…
in my 3rd or 4th fuel tank from different garages .. no difference.
What we gonna do later?
A good test for MAF is to idle the truck and then unplug the MAF. It should work significantly weaker.
Also, monitor your 02 sensor voltages while idling and driving, if you can. The two upstream sensors (bank 1 sensor 1 and bank 2 sensor 1) should alternate between high and low voltage. Let’s just say .8 V to .2V as an example. If they’re not reading anything at the .45 level, this is normal initially, but should disappear after the truck warms up. If it’s stuck at 45 or if the voltage is at any static reading and doesn’t fluctuate between above 0.5v and below 0.5v then this is most likely your problem. O2 sensors are still good for a change after about 100k miles.
Go with BOSCH sensors and replace 4 of them simultaneously or at least in pairs (both row sensor 1 or sensor 2), if that makes sense
I know you said your 02 sensor is fine but I fought it for the better part of the year so I thought I’d share it…
I’m not sure if it smells of fuel in the exhaust though … maybe I’m wondering if there’s a plug somewhere and if it fills the tank completely. I’m not sure about the possible hood of this but whatever it is, a little more info – this is a 25-gallon tank and I can usually fill 18 gallons when I’m in a quarter tank, and when I get the low fuel light I can usually fill about 22 gallons.
Edit: I’m also trying to think of something else, I’ve heard stuck open injectors that lead to gas scented oil, misfires, obviously more fuel consumption, but you don’t have anything other than poor gas mileage, so you’re throwing everything in there.
I’m using a Foxwell NT510, I believe it’s programmed to interface with Land Rovers. I can also reset adaptations that almost immediately reset what the computer has learned about how your engine works (fuel trim, etc.). If you’ve replaced sensors like the 02 sensor or MAF, I think it would be a good idea to reset them if you can. The Foxwell unit is only like $ 100 USD and allows you to do a decent amount in cross-country and others. You can simulate this by removing the battery and holding it for x long, but I can’t verify this.
If you can I can start here
After replacing all these parts, all you have to do is look at the raw data and determine which part is faulty or is getting an abnormal reading and post your findings here. MAF reading, 02 voltages, etc. data like. The OBD tool you own usually has a function that allows you to save data.
Finally resolved!
The problem seems to be solved… after visiting the mechanic the other day….!
code reader showed an error on MAF sensor…. it was initially downloaded to disconnect while working to see what the change in idle state would be, in which case there was no change.
Error code cleared ,,,, maf sensor removed for visual inspection… looked clean but still sprayed with MAF sensor cleaner and replaced.
the car did not work differently at this stage…. so it works fine… .. started the tank normally and refilled after a few days…. now my truck is not working differently but fuel economy has returned to normal ……!
I ordered the new MAF as stated…
Symptom:
Using excessive amounts of fuel
Nowhere is fuel leaking and the fuel gauge reads correctly… not driving differently, no noticeable fuel smelling exhaust or anything else.
What to do next and the possible cause:
Definitely check trouble codes with a LR-specific diagnostic tester.
Drive your Disco without MAF cable connector connected. If the problem remains the same, it usually means a bad MAF sensor.
Update:
ok… just arrived from the garage… everything is checked and no code… trim is good… oxy sensors are good… .tps good… coolant sensor – good… start up or sprayed% $ d – no leaks detected…. MAF is clean ……. clean air filter – oil free type …… no fuel smell from exhaust… no fuel leak…. It runs 98 octane fuel as usual… ..
the mechanic is thinking about replacing the MAF (he would have done at least 100k + km) anyway to see what happens… and also the evap drain valve as this could cause problems…?
in my 3rd or 4th fuel tank from different garages .. no difference.
What we gonna do later?
A good test for MAF is to idle the truck and then unplug the MAF. It should work significantly weaker.
Also, if you can, monitor your 02 sensor voltages while idling and driving. The two upstream sensors (bank 1 sensor 1 and bank 2 sensor 1) should alternate between high and low voltage. Let’s just say .8 V to .2V as an example. If they are at the .45 level they don’t read anything, this is normal at the beginning but should disappear after the truck warms up. If it’s stuck at 45, or if the voltage is at any static reading and doesn’t fluctuate between above 0.5v and below 0.5v, then this is most likely your problem. O2 sensors are still good for a change after about 100k miles.
Go with BOSCH sensors and replace 4 of them simultaneously or at least in pairs (both row sensor 1 or sensor 2), if that makes sense
I know you said your 02 sensor is fine but I fought it for the better part of the year so I thought I’d share it…
I’m not sure if it smells of fuel in the exhaust though … maybe I’m wondering if there’s a plug somewhere and I haven’t completely filled the tank. I’m not sure about the possible hood of this, but whatever it is, a little more information – this is a 25-gallon tank and I can usually fill 18 gallons when I’m in a quarter tank, and when I get the low fuel light I can usually fill about 22 gallons.
Edit: Also trying to think of something else, I’ve heard stuck open injectors that lead to gas scented oil, misfires, obviously more fuel consumption, but you have nothing but poor gas mileage, so you’re throwing everything in there.
I’m using a Foxwell NT510, I believe it’s programmed to interface with Land Rovers. I can also reset adaptations that almost immediately reset what the computer has learned about how your engine works (fuel trim, etc.). If you’ve replaced sensors like the 02 sensor or MAF, I think it would be a good idea to reset them if you can. The Foxwell unit is only like $ 100 USD and allows you to do a good amount in cross-country and others. You can simulate this by removing the battery and holding it for x times, but I can’t verify this.
If you can I can start here
After replacing all these parts, all you have to do is look at the raw data and determine which part is faulty or is getting an abnormal reading and post your findings here. MAF reading, 02 voltages, etc. data like. The OBD tool you own usually has a function that allows you to save data.
Finally resolved!
The problem seems to be solved… after visiting the mechanic the other day….!
code reader showed an error on MAF sensor…. it was initially downloaded to disconnect while working to see what the change in idle state would be, in which case there was no change.
Error code cleared ,,,, maf sensor removed for visual inspection… looked clean but still sprayed with MAF sensor cleaner and replaced.
the car did not work differently at this stage…. so it works fine… .. started the tank normally and refilled after a few days…. now my truck is not working differently but fuel economy has returned to normal ……!
I ordered the new MAF as stated…
