I own a 2004 (new shape) F150 4.6l XLT.

So far I have:

- Cleaned the MAF with MAF Cleaner,
- Cleaned the Throttle Body with TB Cleaner,
- Cleaned AiRaid air filter,
- Changed all plugs,
- Changed all coil boots and replaced coil #1 which had a broke clip.

However, I am still experiencing a very rough idle when in Neutral or Park, no matter what temperature the engine is at. In addition, I quite often experience a strong smell of gas in the cab at startup.

I have purchased an OBDLink MX OBD adaptor and installed both ForScan and Torque Pro. I am very new to OBD diagnostics so would appreciate some help and advice on how to read the results and what graphs to create.

Below are my Torque Pro Mode $06 test results. There are a couple items which have failed and a couple of very small count misfires (cylinder #4 and #7). Would this be enough misfires to cause such a poor idle?

[CODE]Mode $06 report generated by Torque for Android
================================================

Test report:
------------------
MID:$01 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 1 Sensor 1
Max: 7.99527V Min: 0V
Test result value: 0.49996V
PASS
----
MID:$01 TID:$80
- O2 Bank 1 Sensor 1
Max: 7.99527V Min: 0.50996V
Test result value: 0.75518V
PASS
----
MID:$01 TID:$81
- O2 Bank 1 Sensor 1
Max: 3A Min: 0.23A
Test result value: 0.477A
PASS
----
MID:$02 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 1 Sensor 2
Max: 7.99527V Min: 0V
Test result value: 0.44994V
PASS
----
MID:$02 TID:$81
- O2 Bank 1 Sensor 2
Max: 3A Min: 0.23A
Test result value: 0.468A
PASS
----
MID:$03 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 1 Sensor 3
Max: 7.99527V Min: 0V
Test result value: 0.44994V
PASS
----
MID:$03 TID:$81
- O2 Bank 1 Sensor 3
Max: 3A Min: 0.23A
Test result value: 0A
FAIL
----
MID:$05 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 2 Sensor 1
Max: 7.99527V Min: 0V
Test result value: 0.49996V
PASS
----
MID:$05 TID:$80
- O2 Bank 2 Sensor 1
Max: 7.99527V Min: 0.50996V
Test result value: 0.73883V
PASS
----
MID:$05 TID:$81
- O2 Bank 2 Sensor 1
Max: 3A Min: 0.23A
Test result value: 0.481A
PASS
----
MID:$06 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 2 Sensor 2
Max: 7.99527V Min: 0V
Test result value: 0.44994V
PASS
----
MID:$06 TID:$81
- O2 Bank 2 Sensor 2
Max: 3A Min: 0.23A
Test result value: 0.486A
PASS
----
MID:$07 TID:$01
Rich to Lean sensor threshold voltage(constant) - O2 Bank 2 Sensor 3
Max: 7.99527V Min: 0V
Test result value: 0.44994V
PASS
----
MID:$07 TID:$81
- O2 Bank 2 Sensor 3
Max: 3A Min: 0.23A
Test result value: 0A
FAIL
----
MID:$10 TID:$0e
- O2 Bank 4 Sensor 4
Max: 0 Min: 0
Test result value: 48,000
FAIL
----
MID:$21 TID:$80
- Catalyst Monitor Bank 1
Max: 0.68749Ratio Min: 0Ratio
Test result value: 0.19531Ratio
PASS
----
MID:$22 TID:$80
- Catalyst Monitor Bank 2
Max: 0.68749Ratio Min: 0Ratio
Test result value: 0.12109Ratio
PASS
----
MID:$31 TID:$80
- EGR Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$31 TID:$81
- EGR Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$31 TID:$84
- EGR Monitor Bank 1
Max: 3.332kPa Min: -32.768kPa
Test result value: -2.118kPa
PASS
----
MID:$31 TID:$85
- EGR Monitor Bank 1
Max: 32.767kPa Min: 1.494kPa
Test result value: 15.364kPa
PASS
----
MID:$32 TID:$82
- EGR Monitor Bank 2
Max: 32.164kPa Min: -32.768kPa
Test result value: -2.189kPa
PASS
----
MID:$32 TID:$83
- EGR Monitor Bank 2
Max: 32.767kPa Min: -4.274kPa
Test result value: -2.189kPa
PASS
----
MID:$32 TID:$84
- EGR Monitor Bank 2
Max: 3.332kPa Min: -32.768kPa
Test result value: -2.118kPa
PASS
----
MID:$32 TID:$85
- EGR Monitor Bank 2
Max: 32.767kPa Min: 1.494kPa
Test result value: 15.364kPa
PASS
----
MID:$3a TID:$80
- EVAP Monitor (cap off)
Test incomplete or dependant test failed
--
MID:$3a TID:$81
- EVAP Monitor (cap off)
Test incomplete or dependant test failed
--
MID:$3a TID:$82
- EVAP Monitor (cap off)
Test incomplete or dependant test failed
--
MID:$3b TID:$80
- EVAP Monitor (0.090")
Max: 830.75Pa Min: -8,192Pa
Test result value: 401.5Pa
PASS
----
MID:$3c TID:$80
- EVAP Monitor (0.040")
Test incomplete or dependant test failed
--
MID:$3e TID:$f4
- Purge Flow Monitor
Max: 57,211 Min: 10,319
Test result value: 65,523
FAIL
----
MID:$81 TID:$05
Rich to Lean sensor switch time(calculated) - Fuel System Monitor Bank 1
Max: 57,374 Min: 22,544
Test result value: 65,520
FAIL
----
MID:$a1 TID:$80
- Misfire Monitor General Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a1 TID:$81
- Misfire Monitor General Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a1 TID:$82
- Misfire Monitor General Data
Max: 32.99975% Min: 0%
Test result value: 0.24874%
PASS
----
MID:$a1 TID:$83
- Misfire Monitor General Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a1 TID:$84
- Misfire Monitor General Data
Max: 966.60004°C Min: 0°C
Test result value: 529.40002°C
PASS
----
MID:$a2 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 1 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a2 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 1 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a2 TID:$80
- Misfire Cylinder 1 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a2 TID:$81
- Misfire Cylinder 1 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a3 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 2 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a3 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 2 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a3 TID:$80
- Misfire Cylinder 2 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a3 TID:$81
- Misfire Cylinder 2 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a4 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 3 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a4 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 3 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a4 TID:$80
- Misfire Cylinder 3 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a4 TID:$81
- Misfire Cylinder 3 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a5 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 4 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a5 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 4 Data
Max: 65,535 Min: 0
Test result value: 1
PASS
----
MID:$a5 TID:$80
- Misfire Cylinder 4 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a5 TID:$81
- Misfire Cylinder 4 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a6 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 5 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a6 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 5 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a6 TID:$80
- Misfire Cylinder 5 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a6 TID:$81
- Misfire Cylinder 5 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a7 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 6 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a7 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 6 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a7 TID:$80
- Misfire Cylinder 6 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a7 TID:$81
- Misfire Cylinder 6 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a8 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 7 Data
Max: 65,535 Min: 0
Test result value: 5
PASS
----
MID:$a8 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 7 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a8 TID:$80
- Misfire Cylinder 7 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a8 TID:$81
- Misfire Cylinder 7 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$a9 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 8 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a9 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 8 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$a9 TID:$80
- Misfire Cylinder 8 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$a9 TID:$81
- Misfire Cylinder 8 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$aa TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 9 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$aa TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 9 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$aa TID:$80
- Misfire Cylinder 9 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$aa TID:$81
- Misfire Cylinder 9 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$ab TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 10 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ab TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 10 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ab TID:$80
- Misfire Cylinder 10 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$ab TID:$81
- Misfire Cylinder 10 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$ac TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 11 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ac TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 11 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ac TID:$80
- Misfire Cylinder 11 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$ac TID:$81
- Misfire Cylinder 11 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$ad TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 12 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ad TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 12 Data
Max: 65,535 Min: 0
Test result value: 0
PASS
----
MID:$ad TID:$80
- Misfire Cylinder 12 Data
Max: 32.99975% Min: 0%
Test result value: 0%
PASS
----
MID:$ad TID:$81
- Misfire Cylinder 12 Data
Max: 1.49853% Min: 0%
Test result value: 0%
PASS
----
MID:$d0 TID:$0e
-
Max: 0 Min: 0
Test result value: 48,000
FAIL
----
MID:$e1 TID:$05
Rich to Lean sensor switch time(calculated) -
Max: 57,373 Min: 6,160
Test result value: 65,520
FAIL
----


End of report.
[/CODE]

 

Check injectors for leakage.

 

Yep. Also disregard all tests that reference sensor 3 and 4 - you don't have any. You have a sensor 1 and sensor 2 on each bank. You may also have a problem with the evap system.

 

I know I sound like a "one trick pony" too, but my money's also on the evap system. I think you have a saturated canister.

- Jack

 

I'd also lay money on a saturated canister if you are in the habit of completely topping off your tank when you fill it.

 

saturated canister, fuel injector & fuel rail leakage. Start engine with the hood open ,I would look around the top of the motor for signs of gas leakage, could be coming in the cab from heating air inlet system. if not, Canister!

 

I couldn't believe the coincidence having just posted this thread. But having got in the truck yesterday morning, I heard a rattle ONLY at 700rpm. Sounds like one of the catalytic converters have failed!

The truck has been converted to LPG and has been run on a somewhat lean mixture by the previous owner for some 50,000 miles. I wonder whether this has finally destroyed one of the cats?

As a worst case scenario, my fear now is whether the rough idle could be caused by recessive valve seats .

Due the truck always being run on LPG, the fuel tank rarely is filled more than a 1/4. Could the canister still be saturated by another means?

Could a failing cat also cause a rough idle and a gas smell every now and again?

 

I ran some OBD tests which are below, can you guys see anything obvious from these which may be causing the rough idle?

 

if the truck has been converted to LPG, may be they did some of the vent lines to the gas tank?? Is the conversion removed?? Is the smell like fresh or old gas? catalytic converters have tin covers that come loose and make noise. Just find the one and bend its cover away from the cat. a little w/ screw driver or re-weld,or remove the cover completely.

 

Until recently the truck ran well with no rough idle. The LPG system has always been lean which is something I will get around to correcting.

The gas smell only comes about every now and again (every couple of weeks or so). It smells like fresh gas.

 

Does the smell come with a fill up or low fuel in the tank? I have seen gas smell coming from around the fuel pump (Big O-ring) leaking gas on a full tank and not setting any codes.
Look for stains on the sides and bottom of the tank. ??