MPG Prob. & Detailed DTC Disctription Need Help
Thread Starter
Joined: 09-24-06
Posts: 4,535
Likes: 196
From: Virginia Beach, VA
MPG Prob. & Detailed DTC Disctription Need Help
Well I've been having problems with MPG. Its very low for for the 2.2. Sometimes I get 30 MPG but that not very often. It's been around 22 for the past few weeks and iI can't figure out what the problem is. I changed an o2 sensor and it jumped from 18 to 22. I don't really know how use full this info is going to be as in trying to figure out what is wrong, but maybe someone can help me understand it. Also there is a good amount of black soot on the exhaust tip, I didn't think it looked normal
Here are the trouble codes
P0171 - System Too Lean (Bank 1)
P1174 - Manufacturer Control Fuel Air Metering
Here is the freeze data my scanner gave me
Throttle Position: 18.8%
Engine RPM: 771 RPM
Barometric Pressure: 102 KPA
Load Value: 18.0
Air Flow Rate: 2.26 GR/sec
MAP Sensor: 27KPA
Ambient Air Temp: 66*F
Coolant Temp: 192*F
Intake Air Temp: 93*F
Ignition Timing Advance: 10.0 Deg
Short Term Fuel Trim1: 32.0%
Long Term Fuel Trim1: 29.6
Short Term Fuel Trim3: 32.8%
Long Tern Fuel Trim3: 32.8%
Vehicle Speed: 0 MPH
Absolute Load Value: 13.0%
Fuel System 1: Closed
Fuel System 2: N/A
Relative Throttle Position: 5.0%
Commanded Throttle Position: 7.4%
Accelerator Pedal Position D: 19.6%
Accelerator Pedal Position E: 9.4%
Catalyst Temp Bank 1: 1004*F
Commanded Evap Purge: 10.1%
Evap Vapor Pressure: 3.854 H2O
Commanded Equivalence Ratio: 0.999
Distance Traveled Since Codes Cleared: 52 MI
Fuel Level Input: 63.5%
Control Modual Voltage: 13.890 V
Time Since engien start: 1 min 41 Sec
Here are the trouble codes
P0171 - System Too Lean (Bank 1)
P1174 - Manufacturer Control Fuel Air Metering
Here is the freeze data my scanner gave me
Throttle Position: 18.8%
Engine RPM: 771 RPM
Barometric Pressure: 102 KPA
Load Value: 18.0
Air Flow Rate: 2.26 GR/sec
MAP Sensor: 27KPA
Ambient Air Temp: 66*F
Coolant Temp: 192*F
Intake Air Temp: 93*F
Ignition Timing Advance: 10.0 Deg
Short Term Fuel Trim1: 32.0%
Long Term Fuel Trim1: 29.6
Short Term Fuel Trim3: 32.8%
Long Tern Fuel Trim3: 32.8%
Vehicle Speed: 0 MPH
Absolute Load Value: 13.0%
Fuel System 1: Closed
Fuel System 2: N/A
Relative Throttle Position: 5.0%
Commanded Throttle Position: 7.4%
Accelerator Pedal Position D: 19.6%
Accelerator Pedal Position E: 9.4%
Catalyst Temp Bank 1: 1004*F
Commanded Evap Purge: 10.1%
Evap Vapor Pressure: 3.854 H2O
Commanded Equivalence Ratio: 0.999
Distance Traveled Since Codes Cleared: 52 MI
Fuel Level Input: 63.5%
Control Modual Voltage: 13.890 V
Time Since engien start: 1 min 41 Sec
Thread Starter
Joined: 09-24-06
Posts: 4,535
Likes: 196
From: Virginia Beach, VA
Yes look at the long term and short term fuel trims.
Think about it like this, those numbers tell you how much fuel needs to be added or subtracted for the car to run correctly.
The car thinks it's running lean and is dumping a lot of fuel. If it were running correctly it might add 5% more fuel but not 30% more.
Check all intake and TB connection, make sure MAF and throttle body are clean.
Think about it like this, those numbers tell you how much fuel needs to be added or subtracted for the car to run correctly.
The car thinks it's running lean and is dumping a lot of fuel. If it were running correctly it might add 5% more fuel but not 30% more.
Check all intake and TB connection, make sure MAF and throttle body are clean.
Unmetered air is entering the system and leaning the car out, hence the P1174 code.
This is the cause for both the over shot fuel trims and the P0171 code.
Check for a leaky intake manifold gasket, TB gasket, loose intake piping after the MAF, or even a vacuum hose that may have come loose.
If you don't find anything, it is possible that your MAF or EVAP system is pooched.... pretty unlikey though, considering that both the MAF and EVAP look good on that scan.
This is the cause for both the over shot fuel trims and the P0171 code.
Check for a leaky intake manifold gasket, TB gasket, loose intake piping after the MAF, or even a vacuum hose that may have come loose.
If you don't find anything, it is possible that your MAF or EVAP system is pooched.... pretty unlikey though, considering that both the MAF and EVAP look good on that scan.
Thread Starter
Joined: 09-24-06
Posts: 4,535
Likes: 196
From: Virginia Beach, VA
No my scanner will only read DTC's and give me the Freeze data from the CEL. I would need more of a data logger to get that info
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