2011 LR4 - MPG getting worst

[stufrowin]

I like BG 44K, too. Also SeaFoam. But I am not sure that is going to clean up that sludge and carbon. I haven't seen anything that bad since I worked on a 64 Continental that hadn't had its oil changed in a few YEARS.

But then again, I don't go around pulling manifolds . . . Does this suggests our intake valves mirror this (?).

What will work on this mess?

This was when my water pump/crossover pipe went at 60k MY11 was running perfectly with descent MPG. I had no idea mine were so nasty. So yeah I'd say its safe to say yours is probably gunked as well. Before this I routinely used seafoam and BG 44k in fuel, as well as "top tier fuel" after this I have been using the spray cleaner through the throttle body with the engine running, curious to see if I have been able to keep them cleaner. Won't know until I pull it apart again.

 

[djkaosone]

Quick update: I ran the CRC Intake Valve Cleaner according to the instructions to the tee, it coughed, it ran smoothly afterwards, but I feel that it could be cleaned out some more. My WiFi endoscope came in, and I'll try to get a look from the inside to see what I'm dealing with before I blow another can cleaning it.

Over 110 miles and 8.278 gallons I got 13.3 mpg. I didn't check the fuel trims.

I swapped the wheels out to my street tires on 22" and full of gas, I'll see what I get over the next couple of days.

 

[codemunky]

I'm not sure how you guys are getting 18-20 MPG. Are you guys V6?

On street, I average 12 MPG. Highway, 15-16 at best. I'm on AT off-road tires.

Fuel tank is 22 gallons.

 

[iSurfvilano]

I'm not sure how you guys are getting 18-20 MPG. Are you guys V6?

On street, I average 12 MPG. Highway, 15-16 at best. I'm on AT off-road tires.

Fuel tank is 22 gallons.

I have a '15 w/SCV6 and average 18.5mpg with a set of duratracs. Had a '16 LR4 with the same setup and averaged the same.

 

[mbw]

I'm not sure how you guys are getting 18-20 MPG. Are you guys V6?

On street, I average 12 MPG. Highway, 15-16 at best. I'm on AT off-road tires.

Fuel tank is 22 gallons.

I just did another trip for the eclipse. 7+ hours each way, and the trip back was mostly traffic... 5.0L V8, 55k miles on her, all loaded up again, did 17 to 19 mpg the whole time. I'm still not sure why im getting good mpg lately, but its been great.

 

[codemunky]

I just did another trip for the eclipse. 7+ hours each way, and the trip back was mostly traffic... 5.0L V8, 55k miles on her, all loaded up again, did 17 to 19 mpg the whole time. I'm still not sure why im getting good mpg lately, but its been great.

Do you reset your MPG on every fuelup? I currently Fuelly to track my MPG.

 

[mbw]

Do you reset your MPG on every fuelup? I currently Fuelly to track my MPG.

I just write milage down and check it when I fill up, but its been matching what the computer says pretty closely.

 

[djkaosone]

Quick update: I reset my odometer A right after every fill up and run my calculations. I finally drove it for 109.2 miles and filled it up with 9.184 gallons, which equates to 11.89 mpg. Not a happy camper...

Over the past 4 months I've cleaned (both) MAF, MAP (on top of the TB), TB, CRC Intake valve cleaner (twice), Marvel Mystery Oil, Seafoam, changed spark plugs, changed all fluids (tranny, front diff, rear diff, transfer, and engine), used premium gas only (76, Mobile 1, Chevron, and Shell), changed to on road wheels/tires, and still...

I just did a live data stream with a iCarsoft i930. I'm basically transcribing these numbers from pictures off my cell phone. Hopefully something stands out to someone and they can point me in the right direction. Any help appreciated!!!

Fuel system 1 status: CL
Fuel system 2 status: CL
Calculated LOAD Value: 63.5% <--------------------- Seems awfully high for being at idle
Engine Coolant Temperature: 194*F
STFT - Bank 1: 3.9%
LTFT - Bank 1: -7.0% <-------------------- Thinks it's lean, but runs rich
STFT - Bank 2: 3.9%
LTFT - Bank 2: -6.3% <-------------------- Thinks it's lean, but runs rich
Intake Manifold Absolute Pressure: 8.1 inHg
Engine RPM: 610 /min
Vehicle Speed: 0 mph
Ignition Timing Advance for #1 cylinder: 7.0*
Intake Air Temperature: 125*F
Air Flow Rate from Mass Air Flow Sensor: 0.6 lb/min
Absolute Throttle Position: 12.5%
Oxygen Sensor Output Voltage (B1-S2): 0.795V
Short Term Fuel Trim (B1-S2): 1.6%
Oxygen Sensor Output Voltage (B2-S2): 0.730V
Short Term Fuel Trim (B2-S2): 1.6%
OBD requirements: OBD& OBD2
Time Since Engine Start: 279 sec. <------------------------- Rig was warmed up prior to restarting it
Distance Traveled While MIL is Activated: 0 miles
Fuel Rail Pressure: 427.8 psi <-------------------------- Is this normal?
Commanded Evaporative Purge: 16.9%
Fuel Level Input: 95.7% <------------------------- Full tank? I drove 2 miles home
Number of warm-ups since DTCs cleared: 45
Barometric Pressure: 30.0 inHg
Equivalence Ratio (lambda) (B1-S1): 0.997
Oxygen Sensor Current (B1-S1): -0.01 mA
Equivalence Ratio (lambda) (B2-S1): 1.014
Oxygen Sensor Current (B2-S1): 0.02 mA
Catalyst Temperature Bank 1, Sensor 1: 1373*F
Catalyst Temperature Bank 2, Sensor 1: 1373*F
Control module voltage: 13.75V
Absolute Load Value :15.3%
Fuel/Air Commanded Equivalence Ratio: 1.011
Relative Throttle Position: 1.2%
Ambient air temperature: 86*F
Absolute Throttle Position B: 30.2%
Accelerator Pedal Position D: 15.3%
Accelerator Pedal Position E: 7.8%
Command Throttle Actuator Control: 18.8%
Short Term Sec. O2 Sensor Fuel Trim-B1: -1.6%
Long Term Sec. O2 Sensor Fuel Trim-B1: 0.0%
Short Term Sec. O2 Sensor Fuel Trim-B2: -1.6%
Long Term Sec. O2 Sensor Fuel Trim-B2: 0.0%

 

[jhartz]

Although I can't see 22 inch tires helping gas mileage, it shouldn't make that much of a difference. When you changed out the tires did you look at the brakes -- a dragging brake (s) would have huge effect on MPG.

Next, we need to address the low LTFTs, although balanced, they are too low. Maybe grab your propane torch, open the gas valve and run it along the manifold and throttle body gaskets. Looking for a change in idle.

Any starting problems hot or cold? Looking for a bad temperature sensor.

The 5.0 llters have a much higher fuel rail pressure than the older 4.4 and 4.2SC units, yours appears normal for idle speed.

 

[djkaosone]

When you changed out the tires did you look at the brakes -- a dragging brake (s) would have huge effect on MPG.

Yes, I checked the rear by attempting to spin the rear rotor(s). It's tough to spin a 4x4, but as far as I can tell it doesn't drag during the partial rotation.

Next, we need to address the low LTFTs, although balanced, they are too low. Maybe grab your propane torch, open the gas valve and run it along the manifold and throttle body gaskets. Looking for a change in idle.

I'll give that a shot.

Any starting problems hot or cold? Looking for a bad temperature sensor.

I don't have any issues starting in 100+*F weather and just fine in 40*F (camping somewhere before summer), guessing the temp sensor is ok.