Question about 2003 GMC Yukon Denali

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2003 Yukon 5.3 showing bank 1 lean. All 4 plugs on the left side of the motor were carbon covered. Changed plugs and wires. O2 sensor was carbon covered and black, cleaning changed nothing.New O2 sensor changed nothing. Just had Tranny rebuilt and I noticed that the wiring harness runs right over the top of the tranny.

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I would take a close look at the MAF sensor. Cleaning or replacing it should solve your problem. Just in case you are using an oiled air filter this is the cause of the dirty MAF sensor. Stop using an oiled filter and switch back to a conventional filter. You may also have a vacuum leak downstream of the MAF sensor. Either of these problems will cause a lean condition. Clean the MAF sensor with brake cleaner or a good electronic cleaner. I suggest you remove it to give it a good cleaning. Be careful not to damage the sensor while cleaning. Check all the vacuum hoses and replace as necessary. Do them one at a time as to not get confused.

Posted on Jul 16, 2010


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What does this mean ? P1313 Misfire Rate Catalyst Damage Fault - Bank 1

This is an ignition error. that could one of several things wrong. since it is noted in Bank 1 it is a problem with the right side of the engine Cylinders 1, 3 or 5. located under the intake manifold (close to the firewall)
Other causes:
1. Fouled plug (cylinders 1, 3 or 5)
2. Bad ignition Coil (cylinders 1, 3 or 5)
3. Wire fault to Coils (cylinders 1, 3 or 5)
4. Fault with the O2 sensors (Right side bank 1)

1. Start by checking /changing the plugs. You have to remove the intake manifold to get to plugs (cylinders 1, 3 or 5). if the mileage is high and they have not been changed, then its probably due.
2. Inspect the coil wires for cracks or faults.
3. Swapping the coils cylinders 2, 4 & 6 for cylinders 1, 3 & 5. if the fault changes to bank 2 then you have a bad coil on 2, 4 or 6.

Oct 01, 2014 | 2003 Jaguar X-Type

1 Answer

Engine codes displayed on OBD tool

You might want to start with spark plugs. I'm not sure if that year has coil on plug ignition, but if it doesn't, spark plug wires are probably in order as well. Some of the O2 sensor faults could be caused by the poor ignition your mis-fires are causing. Sensor 1 is closest to the engine, sensor 2 is further away, on the other side of the Catalytic converter.

May 09, 2017 | BMW 325Ci Cars & Trucks

1 Answer

How to find codes for check engine light on

Check Engine Light Codes and Meanings
Long blinks Short blinks Problem
1 1 Camshaft position sensor
1 2 Mass air flow sensor
1 3 Engine coolant temperature sensor
1 4 Speed sensor
1 11 EVAP control system (flow)
1 14 Fuel injection system right bank (too rich)
1 15 Fuel injection system right bank (too lean)
2 1 Ignition circuit
2 3 Closed throttle position switch
2 5 Idle speed control
2 9 Fuel Injection system left bank (too rich)
2 10 Fuel Injection system left bank (too lean)
3 1 ECU
3 2 Exhaust gas recirculation system flow problem
3 3 Front left O2 sensor
3 4 Knock sensor
3 5 Exhaust gas recirculation temperature sensor
3 6 EGRC-BPT valve
3 7 Closed loop control
3 8 Closed loop control
4 1 Air intake temperature sensor
4 2 Fuel tank temperature sensor
4 3 Throttle position sensor
4 7 Crankshaft position sensor
5 3 Front right O2 sensor
5 4 Automatic transmission control unit
6 3 Cylinder #6 misfire
6 4 Cylinder #5 misfire
6 5 Cylinder #4 misfire
6 6 Cylinder #3 misfire
6 7 Cylinder #2 misfire
6 8 Cylinder #1 misfire
7 1 Multiple cylinder misfire
7 2 Three way catalytic converter (right side)
7 3 Three way catalytic converter (left side)
7 4 Evaporative emission control system pressure sensor
7 5 Evaporative emission control system
7 7 Rear O2 sensor
8 1 Vacuum cut valve bypass valve
8 2 Crank position sensor
8 3 Absolute pressure sensor
8 4 Automatic transmission control unit
8 6 Evaporative emission canister purge control solenoid valve
8 7 Evaporative emission Canister purge control solenoid valve circuit
9 1 Front Right O2 sensor
9 3 Evaporative emission Canister vent control valve
9 5 Crankshaft position sensor
9 8 Engine coolant temperature sensor
10 1 Front left O2 sensor
10 3 Park and Neutral position switch
10 5 EGRC solenoid valve
10 8 Evaporative emission canister purge volume control valve
11 1 Inhibitor switch
11 2 Revolution sensor
11 3 Improper shifting to first gear (Automatic transmission)
11 4 Improper shifting to second gear (Automatic transmission)
11 5 Improper shifting to third gear (Automatic transmission)
11 6 Improper shifting to fourth gear (Automatic transmission)
11 7 Solenoid valve lock up function
12 1 Shift solenoid B (Automatic transmission)
12 3 Overrun clutch solenoid valve (Automatic transmission)
12 4 Torque converter clutch solenoid valve (Automatic transmission)
12 5 Line pressure solenoid valve (Automatic transmission)
12 6 Throttle position sensor (Automatic transmission)
12 7 Engine speed signal
12 8 Fluid temperature sensor
13 2 MAP/BARO Switch Solenoid Valve
13 5 Fuel pump control module
13 8 Cooling fan

Dec 12, 2011 | 1995 Nissan Maxima

2 Answers

2003 kia sedona rough idle--check engine light comes on with codes on 1-3-5-cylinder misfires--plugs have been changed, wires changed----it is a replacement engine which had about 70,000 miles on it with...

The only thingI can say is that there is a problem that is affecting the entire bank on one side of the engine. This automatcally eliminates things like Mass Air Flow (MAF) sensor, Manifold Absolute Pressure (MAP) sensor, Throttle Position Sensor (TPS), Crankshaft Position Sensor (CKP) etc. because failure of these things will affect BOTH banks, not one.

I have seen things like a totally skewed upstream Oxygen sensor on one side cause misfire codes for all cylinders on one bank. It is pretty rare, but it CAN happen. This can usually be verified by graphing the O2 Sensor PIDs for both sensors and comparing the graphs.

If the scaner data should be showing SOMETHING that is not right on one side - i.e. fuel trims, injector pulse width, etc.
I would also be looking into the possibility of one of the cams on that side to be 1 tooth off of the correct timing. This can cause problems while the engine is running and will not necessarily show up on a cranking compression test. One way to verify this is to perform a RUNNING compression test. With a warmed-up engine, pull one spark plug out at a time and check the compression with the engine running. Do BOTH sides, so you can compare the readings. If the entire 1-3-5 bank is lower than the 2-4-6 bank, then valve timing is most likely the cause.

Oct 15, 2011 | 2003 Kia Sedona

1 Answer

2006 hundai elantra P2270 code. If this is an O2 sensor, which one?

Possible O2 sensors:

P2270 O2 Sensor Signal Stuck Lean Bank 1 Sensor 2
P2271 O2 Sensor Signal Stuck Rich Bank 1 Sensor 2
P2272 O2 Sensor Signal Stuck Lean Bank 2 Sensor 2
P2273 O2 Sensor Signal Stuck Rich Bank 2 Sensor 2
P2274 O2 Sensor Signal Stuck Lean Bank 1 Sensor 3
P2275 O2 Sensor Signal Stuck Rich Bank 1 Sensor 3
P2276 O2 Sensor Signal Stuck Lean Bank 2 Sensor 3
P2277 O2 Sensor Signal Stuck Rich Bank 2 Sensor 3
P2278 O2 Sensor Signals Swapped Bank 1 Sensor 3 / Bank 2 Sensor 3
This is Bank 1 (closer to the dash panel) Sensor 2 (located after the catalytic converter).

Note: A malfunctioning front oxygen sensor may cause fuel trim codes to set.
  1. Several Diagnostic Trouble Codes use specific terminology to refer to sensor location. The illustration and key below explain the following terms:
  2. Engine BANK Bank 1 is closer to the dash panel, (also referred to as RH or right hand). Bank 2 is closer to the radiator, (also referred to as LH or left hand).
  3. UP Refers to Sensor 1 or "front sensor". It is located closer to the exhaust manifold and before the catalytic converter.
  4. DOWN Refers to Sensor 2 or "rear sensor." It is located after the catalytic converter.
  5. The following examples show how to interpret oxygen sensor terminology:
  6. B1/S1 = Bank 1/Sensor 1 = Dash panel side, BEFORE the catalyst or "upstream"
  7. B2/S2 = Bank 2/Sensor 2 = Radiator side, AFTER the catalyst or "downstream"

Aug 06, 2010 | Hyundai Elantra Cars & Trucks

1 Answer

Where is bank one oxygen sensor located at on a 2003 yukon

Need more information but here is where all your O2 sensors are located
Bank 1 Sensor 1 - Driver's side, before catalytic converter Bank 1 Sensor 2 - Driver's side, after catalytic converter
Bank 2 Sensor 1 - Passenger side, before catalytic converter
Bank 2 Sensor 2 - Passenger side, after catalytic converter

Thank you for using fixya and good luck

May 13, 2010 | 2003 GMC Yukon XL

4 Answers

Having problem with check engine light its showing that theirs a lean on bank 2 code P0174/P0171 what would be the cause could it be my cadaylac converter

what this codes indicates is you are running lean on both sides of the motor 171 is right side and 174 is left side.

Lean means either low fuel pressure or big vacuum leak. Since you have no cylinder misfires I would inspect the MAF sensor first. If you installed a K/N filter the oil on it could of contaminated the MAF sensor fine wires. Or you may have a air filter that is clogged.
You can clean the MAF with brake clean being careful not to break the wires.
Or inspect for a large vacuum leak that could affect both sides.
Or if all else fails have the fuel pressure checked.

14.7.1 part air to 1 part fuel is what the computer tries to maintain
.It needs this to get the best bang for the buck

A big vacuum leak or low fuel pressure will change this
If the computer sees a big vacuum leak it will add fuel until it cant anymore. This is when the code sets.
Same thing for low pressure. It will set the code because the engine stays lean for too long.

Dec 02, 2009 | 2003 Chevrolet Tahoe

1 Answer

2003 yukon xl 5.3l flexfuel all plugs lean on passenger side

P0131 - Heated Oxygen Sensor (HO2S) Circuit Low Voltage

P1133 - Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 1 Sensor 1

Bank 1 Sensor 1
P0300 - Engine Misfire Detected

I would check for vacuum leaks, maybe intake or brake booster

Dec 16, 2008 | 2003 GMC Yukon XL

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