Getting Error Codes P0172 And P0174 Help!

[tapate]

I have a 2005 Chevrolet Silverado...5.3 ltr i think... (not positive). Cleaned the o2 sensor at Auto zone but slow start, rough idle, and delayed acceleration continue. Any advice? I think codes say its running too lean. I appreciate any help ya'll can provide, bc i need to get an idea on fixing this issue. Thanks in advance.

[tapate]

I have a 2005 Chevrolet Silverado...5.3 ltr i think... (not positive). Cleaned the o2 sensor at Auto zone but slow start, rough idle, and delayed acceleration continue. Any advice? I think codes say its running too lean. I appreciate any help ya'll can provide, bc i need to get an idea on fixing this issue. Thanks in advance.

 

 

Anyone? Bump it up...

[neto1978]

same thing happened to mine, replaced all the injectors and it's perfect now...

 

Subject: 97-05 Vehicles with 4.8 5.3 5.7 and 6.0 Gen III V8 Engines and Misfires on One Bank - kw CEL diagnostics driveability DTC P0171 P0172 P0174 P0175 P0300 P0301 P0302 P0303 P0304 P0305 P0306 P0307 P0308 #PIP3056 - (07/12/2004)

 

Models: (00-05 Cadillac Escalade - C6 and K6) and (02-05 Chevrolet Avalanche - C1, C2 K1 and K2) and (99-05 Chevrolet Silverado - C1, C2 K1 and K2) and (00-05 Chevrolet Suburban - C1, C2, K1 and K2) and (00-05 Chevrolet Tahoe - C1 and K1) and (99-05 GMC Sierra C1, C2 K1 and K2) and (00-05 GMC Yukon - C1, C2, K1 and K2) and (03-05 Chevrolet Express G1, G2, G3, H1, H2 ) and (03-05 GMC Savana G1, G2, G3, H1, H2 ) and (04-05 Buick Rainier S1, T1 ) and (03-05 Chevrolet Trail Blazer EXT S1, T1 ) and (03-05 GMC Envoy XL XUV S1, T1 ) and (03-05 Hummer H2) and (04-05 Cadillac CTS-V DB) and (98-02 Chevrolet Camaro FB) and (97-04 Chevrolet Corvette YB) and (98-02 Pontiac Firebird FB) and (04-05 Pontiac GTO VB)

 

The following diagnosis might be helpful if the vehicle exhibits the described symptoms.

 

Condition/Concern:

Check Engine Light with a P0300 due to 2 - 4 cylinders misfiring on the same bank of the engine. DTCs P0171, P0172, P0174 or P0175 may also set for the misfiring bank.

 

Recommendation/Instructions:

If the published misfire diagnostic does not isolate the cause, perform the following suggestions as necessary:

 

•Perform a fuel injector balance test for all 8 cylinders. If a fuel injector concern exists, it is possible to misfuel an entire bank of the engine, causing multiple cylinders on the same bank to misfire even though the root cause is a single fuel injector.

•Inspect O2 sensor connections on the misfiring bank for corrosion or water intrusion. If water intrusion is found on the right bank, it may be due to the AC Evaporator Condensation dripping onto the O2 sensor harness. If this condition is found, reposition and shield the harness to prevent a repeat concern and repair the connections.

•Check for excessive exhaust backpressure using the restricted exhaust diagnosis.

•Swap the Position 1 O2 sensors side to side to see if the misfires move to the other bank of the engine. If so, replace the O2 sensor.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

 

NOTE: GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition.

 

 

 

I have a 2005 Chevrolet Silverado...5.3 ltr i think... (not positive). Cleaned the o2 sensor at Auto zone but slow start, rough idle, and delayed acceleration continue. Any advice? I think codes say its running too lean. I appreciate any help ya'll can provide, bc i need to get an idea on fixing this issue. Thanks in advance.

 

 

Anyone? Bump it up...

 

[Bigbadblack]

What does that mean?

 

Basically this means that an oxygen sensor in bank 1 detected a rich condition (too little oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.

 

Note: This DTC is very similar to P0175, and in fact your vehicle may show both codes at the same time.

Symptoms

 

You will more than likely not notice any drivability problems, although there may be symptoms such as a misfire.

Causes

 

A code P0172 may mean that one or more of the following has happened:

 

* The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters can cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.

* There could be a vacuum leak.

* There could be a fuel pressure or delivery problem

 

Possible Solutions

 

Possible solutions include:

 

* Inspect all vacuum and PCV hoses, replace if necessary

* Cleanthe MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling

* Inspect fuel lines for cracks, leaks, or pinches

* Check the fuel pressure at the fuel rail

* Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.

* Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible)