Dec 14, 2023 · Trouble Code - P0171, P0174. Been getting occasional P0171, P0174 codes but the truck (07-13 Silverado 1500) runs great, idles great and is otherwise not having any performance issues at all. I cleaned the MAF, and throttle body, and installed 4 new Oxygen Sensors (Denso) and still getting occasional P0171, P0174 codes. P0172 And P0175 Chevy Silverado Codes: Possible Reasons & Fixes. In short, P0172 refers to bank 1 having a rich fuel mixture to the engine. It’s the same for P0172 but for bank 2 instead. Both of these get triggered by the upstream oxygen sensor in your Chevy Silverado. A rich fuel mixture basically means that there’s either too much fuel ...Fixing a Code P0174 on a 2002 Chevrolet Silverado with Ron Bilyeu - YouTube. AVI ON DEMAND. 14K subscribers. Subscribed. 150. 27K views 4 years ago. …GM may be replacing tens of thousands of Bolt EV batteries, but it won’t have to pick up the tab for most of them. The automaker has reached a deal that will have LG pay nearly all...Chevrolet GMC Involved Region or Country North America, Europe, Uzbekistan, Russia, Middle East, Iraq, Israel, Palestine, ... Initial diagnosis may display any of these misfire and/or fuel trim related codes: • P0300-P0308 • P050D • P0171 • P0172 • P0174 • P0175 • P2099 ... – 2016 SILVERADO 1500 4WD CREW CAB VIN ...Understanding P0101 OBD-II Trouble Code. Headline: Unraveling the Mystery: Decoding the P0101 Diagnostic Trouble Code in a Chevy Silverado. If you’re a dedicated Chevy Silverado aficionado like many of us, this beast’s P0101 Diagnostic Trouble Code (DTC) might be all too familiar.6 years 6 months ago - 6 years 6 months ago #13991. 2008 Chevy Silverado 2500hd 6.0 P0174 and a p0171 was created by drogan. 2008 Silverado 2500 6.0 has a p0171 and a p0174. Intake was smoked with no leaks truck came to me with 8 new injectors a new fuel pump new map and mass air flow sensor and new intake gaskets.I am getting intermittent P0171 and P0174 (O2 sensors) codes along with a very intermittent P0107, P0101, and P0300 (misfires on cylder 1 and 7 and random cylinder misfire). ... A forum community dedicated to Chevrolet Silverado and GMC Sierra pickup owners and enthusiasts. Come join the discussion about performance, modifications, …56 posts · Joined 2009. #1 · Feb 18, 2014. Folks, I'm having some issues with DTC codes P0300 and the random P0171 and P0174. I'm running a Bully Dog GT Gas tuner and KN CAI (recently added and code started shortly after). I've cleaned out the MAF several times, checked the plug wires and coils, check hoses and lines and can't seem to …The cost to diagnose the P0174 2018 Chevrolet Silverado code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.P0300 is wuch a generic code that it’s pretty difficult to pinpoint without first throwing some parts at it. If no improvement after plugs and wires, then it’s probably time to look at fuel system: injectors, fuel pump. 2016 Silverado LT 4x4 Crew Cab. 2017 Suburban LT. 2018 BMW K1600GTL.Feb 12, 2023 · The P0174 code means that the O2 sensor on bank 2 has recognized a too lean mixture, and the imbalance is too great for the O2 sensor to correct the issue on its own. The O2 sensor can correct a fuel mixture of +-15%. If the needed correction is out of this range, the P0174 code will be stored. May 2, 2022 ... 1997 Chevrolet Suburban (Lean codes P0171/P0174) ... System Too Lean - Code P0171 or P0174 on Your Car or Truck ... P0171and P0174 CODES CHEVY VORTEC ...May 24, 2021 · The usual causes of a P0174 code are outdated PCM software, vacuum leaks, a bad mass airflow sensor, faulty fuel pump, and plugging in the fuel filter or fuel injectors. A vehicle that has set the P0174 code can display symptoms like an illuminated check engine light, engine power loss, misfires, and rough idling. One of the most common trouble codes with the Chevy Impala is P0174. It indicates that your Chevy Impala is running lean on the bank two side of the engine. P0174 and P0171 (fuel trim lean bank one) are the most frequently seen air/fuel mixture-related codes. If they appear together, it reduces the list ofHow to fix Chevrolet or GMC P0174 engine code: System Too Lean (Cylinder Bank 2) A P0174 Code is set when the Bank-2 upstream sensor-1 oxygen sensor reports …2012 6.0 vortec gas. p0174 right bank code. ... well, hauling my 67 gran prix to day, the above code came up, pulled into auto zone for diagnosis. as usual, could be anyone of 6 things, so, further researching led me to mass airflow sensor, or o2 sensor as the more usual culprit,, ... A forum community dedicated to Chevrolet Silverado and …Jun 7, 2018 ... In this video, we explain what OBD2 code P0174 means and possible ... System Too Lean - Code P0171 or P0174 on Your Car or Truck. 1A Auto ...Just got the following codes off my truck when the CEL came on: P0101, P0171, P0174, P0327 I pulled the intake all the way off including the manifold, gave it a good cleaning (including the MAF) and drove it around a bit only to have them come back. ... 2006 Chevrolet Silverado 1500HD 4x4 Metallic Silver, Duraline Bed liner, MT Tires …P0171 and P0174 OBD II Trouble Codes. 1 answer. P0131 Gmc HO2S Circuit Low Voltage Bank 1 Sensor 1. P0151 Gmc HO2S Circuit Low Voltage Bank 2 Sensor 1. P0452 Gmc Fuel Tank Pressure Sensor Circuit Low Voltage. P0430 Gmc Catalyst System Low Efficiency Bank 2. 3 answers. 3 answers.2008 Chevy Silverado P1175 was created by Cirp73. 2008 Chevy Silverado 5.3L 125k miles. So I have multiple issues I’m trying to solve. The first issues I have is the check engine light is on and my scanner shows a P1175 code. Now, it also had a P0174 before I cleared the codes after cleaning the Mass Air Flow Sensor and …What Causes the P0174 Code? The most common causes of the P0174 code are the following: Vacuum leak due to damaged intake manifold gaskets or punctured vacuum and positive crankcase …P0174 Diagnosis. To diagnose P0174, a mechanic will typically use an OBD-II scanner or code reader to check for fault codes, and then perform a visual inspection of the engine, fuel system, air intake system, and exhaust system.You could be back to too much air (unmetered) causing the lean condition. Are the P0171, P0174, and P0300 the only codes you have stored? Save Share. Like. P. PJesse Discussion starter ... Chevy Silverado and GMC Sierra Forum. 1.4M posts 183.2K members Since 2009 A forum community dedicated to Chevrolet Silverado and GMC …Billavista.comP0171 ford p0174 code p0344 silverado chevy p2096 dodge p1273 escape ram diagnosis jeep codes nissan trouble wrangler journey murano Paint codeSilverado chevy battery replacing wont. Check Details 2001 silverado paint codes.If you’re looking into buying a dependable new or used truck, you’ve likely come across the 2020 Chevy Silverado in your search. The Silverado is consistently one of the most popul...5. Inspect the exhaust system for any signs of damage or blockages. A damaged or blocked exhaust can cause a fuel mixture imbalance, resulting in a P0175 code. 6. Check the oxygen sensor and replace if necessary. A faulty oxygen sensor can cause a fuel mixture imbalance, resulting in a P0175 code. 7.In this video I have a look at a 2008 Chevrolet Silverado 1500 5.3 that came in with codes P0171 and P0174 indicating that the engine is running lean. It doe...P0121 is an engine code representing a malfunction in the throttle position sensor, which can cause fuel efficiency to drop. To begin, check the air filter and replace it if needed. A clogged air filter restricts airflow and can cause an engine to burn more fuel in order to get the same amount of power.Nov 20, 2022 ... System Too Lean - Code P0171 or P0174 on Your Car or Truck ... Chevrolet, GMC Lean Codes P0171 P0174! My ... Power steering pump replacement / Chevy ...Apr 5, 2019 · A P0174 is a code that says it all. Something is wrong with the exhaust, but until its fixed the car will expunge more fuel. However, what if it was the oxyg... Feb 12, 2023 · The P0174 code means that the O2 sensor on bank 2 has recognized a too lean mixture, and the imbalance is too great for the O2 sensor to correct the issue on its own. The O2 sensor can correct a fuel mixture of +-15%. If the needed correction is out of this range, the P0174 code will be stored. The P0174 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0174 is set in along with the …I have a new body style 2007 GMC sierra vortec max and recently have been getting P0171/P0174 lean conditions in bank 1 and bank 2 and I cant figure it out. SYMPTOMS: Check engine light. Stabilitrak/Traction control off/service randomly comes on, mostly at a stop or lower speeds. Stall/sputter @ idle, especially if started with the remote start ...Diagnostic trouble code P0174 means system too lean bank 2. This means the powertrain control module (PCM) has detected lean conditions in bank 2 in the air-fuel ratio (AFR). Lean conditions mean there is too much air or too little fuel. Bank here means the location of the cylinder head in v-type engines. Check out this article, bank 1 and bank ...Your car or truck has either a P0171, P0174 lean fault code or both stored in the pc, these codes derive from Oxygen Sensor (O-2) readings. A lean code or codes suggest that there surely is too-much air in the exhaust. Bear in mind parts shops have staff members having good motives nonetheless they may not have the experience necessary to ...The P0174 code means that the O2 sensor on bank 2 has recognized a too lean mixture, and the imbalance is too great for the O2 sensor to correct the issue on its …4 days ago ... Code p0174 chevy silverado. Things To Know About Code p0174 chevy silverado. Engine Code P0174: System Too Lean (Bank 2). The fuel system is ...If rough idle (I also got P0300, with P0171, P0174 codes) 1. Check the fuel pressure regulator on the drivers side fuel rail by pulling the vacuum line off. (It is bad if wet with fuel) 2. Check EGR valve is working properly, gasket is good, and the tubes don't have a leak with carb cleaner.Chevrolet is an American icon, known for the Camaro, Corvette, Malibu, Impala and more. Take this quiz to see if you can recognize the most memorable '70s Chevys! Advertisement Adv...Engine Code P0171, P0174. Jump to Latest Follow ... Chevy Silverado EV Forum 2K+ members. Home. Forums. Truck Talk. Engine. Vortec 5300 5.3L V8 ...The following diagnosis might be helpful if the vehicle exhibits the described symptoms. 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. Perform a fuel injector balance test for all 8 cylinders.Aug 10, 2016 · Pulled codes and discovered the "lean codes" P0171 and P0174, There was also a transmission related code, which was not unexpected. Next steps: Removed the transmission and took it for bench rebuild, flushed cooling lines and installed the rebuilt transmission with new torque converter. Cleared codes and road tested. Getting codes P0171 and. 2001 Chev silverado 1500 4.8L. Getting codes P0171 and P0174,. Long term fuel trims pegged at 25%, short term 7%. Cleaned MAF, no change. Installed New O2 sensors and new MAF no change. Checked for open EGR. Now, if I unplug the MAF, the fuel trims go -3% ST and +3% LT. O2 sensors switching as they should.Chevrolet Silverado 1500 (New Model) 2019 2019 Equipped with 5.3L or 6.2L Engine (RPOs L84, L87) All GMC Sierra 1500 (New Model) Involved Region or Country North America Condition Important: If the customer did not bring their vehicle in for this concern,DO NOT proceed with this EI. Some customers may comment one or more of the following condition:Faulty oxygen sensor. Incorrect fuel pressure. Leaking positive crankcase ventilation (PCV) valve. Clogged exhaust gas recirculation (EGR) Port. Leaking brake booster. Repairs to Fix the P0174 Code. The following are some possible repairs for the P0174 code, depending on the source of the issue: Replacing mass air flow sensor.Dec 16, 2008 ... I took it to autozone and had it computered, and it showed a P0171 and P0174 code. Their print out suggested the MAF was bad. After putting ...If you’re looking into buying a dependable new or used truck, you’ve likely come across the 2020 Chevy Silverado in your search. The Silverado is consistently one of the most popul...Feb 26, 2015 · 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. Jun 2, 2021 ... This 2015 GMC was brought in due to rough idle and the MIL on. Scan retrieved codes P0171 and P0174. Problem was under reporting MAF sensor ...Chevrolet Silverado 1500: I have lean codes on a 2001 chevy. I have lean codes on a 2001 chevy silverado motor is the 4.8 codes are p0174 and p0171. I've changed the valve by tank the valve on the top … read more. ZZDaryl. Lead Auto Tech.An engine code P0171 may be caused by one or more of the following: A vacuum leak in the intake manifold or elsewhere in the engine. A leaking or dirty mass airflow sensor (MAF). An exhaust gas recirculation (EGR) system that is not working properly. A faulty oxygen sensor.P0174 code. I ran a P0174 code the other day while driving but the truck ran like normal, had no weird noises, or weird idle. I opened the hood and cleaned the MAF sensor and listened for vacuum leaks but couldn't find anything. I reset the truck but the codes came back after I drive for about an hour. Could use any help.Codes P0171 & P0174. 1997 Silverado 3500 7.4l. ... A forum community dedicated to Chevrolet Silverado and GMC Sierra pickup owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more! Show Less .Nov 22, 2014 · I have a new body style 2007 GMC sierra vortec max and recently have been getting P0171/P0174 lean conditions in bank 1 and bank 2 and I cant figure it out. SYMPTOMS: Check engine light. Stabilitrak/Traction control off/service randomly comes on, mostly at a stop or lower speeds. Stall/sputter @ idle, especially if started with the remote start ... P0121 is an engine code representing a malfunction in the throttle position sensor, which can cause fuel efficiency to drop. To begin, check the air filter and replace it if needed. A clogged air filter restricts airflow and can cause an engine to burn more fuel in order to get the same amount of power.6 years 6 months ago - 6 years 6 months ago #13991. 2008 Chevy Silverado 2500hd 6.0 P0174 and a p0171 was created by drogan. 2008 Silverado 2500 6.0 has a p0171 and a p0174. Intake was smoked with no leaks truck came to me with 8 new injectors a new fuel pump new map and mass air flow sensor and new intake gaskets.8 posts · Joined 2024. #1 · Mar 1, 2024. Hello, 2004, 2500HD, 6.0L, 4X4 with 131,000 miles all original no after market modes. I have P0171 and P0174 codes. My effort. New -. Fuel Tank Pressure Sensor, Gas Cap,Canister Purge Valve, Evap canister vent solenoid, fuel pump (55psi running), Mass flow sensor, air filter. Basically every item new ...One of the most common trouble codes with the Chevy Colorado is P0174. It indicates that your Chevy Colorado is running lean on the bank two side of the engine. P0174 and P0171 (fuel trim lean bank one) are the most frequently seen air/fuel mixture-related codes. If they appear together, it reduces the list of potential causes (more on …P0138 is a common OBDII code that occurs in many vehicles, including the Chevy Silverado. The code is triggered when: The voltage at the sensor remains above threshold for 20 seconds or more. Voltage to the sensor is to high (wiring problem, think short) Bad O2 sensor itself. There are also some less likely problems that can cause P0138.P0121 is an engine code representing a malfunction in the throttle position sensor, which can cause fuel efficiency to drop. To begin, check the air filter and replace it if needed. A clogged air filter restricts airflow and can cause an engine to burn more fuel in order to get the same amount of power.If rough idle (I also got P0300, with P0171, P0174 codes) 1. Check the fuel pressure regulator on the drivers side fuel rail by pulling the vacuum line off. (It is bad if wet with fuel) 2. Check EGR valve is working properly, gasket is good, and the tubes don't have a leak with carb cleaner.A P1174 & P1175 trouble code means that your air to fuel ratio is either running too lean or too rich. Engines will have two banks. In traditional V-shaped engines, the 2-4 cylinders (depending on whether it is a V4 or V8, etc.) on the left side are considered “Bank 1” and the cylinder on the left are considered “Bank 2”.Chevy silverado 2004 1500 code po449 e vap system vent control current low ... I have a 2007 Tahoe with a 5.3 it has three codes p0171 p0174 p0446 I have already replaced the evap canister valve purge solenoid fuel tank pressure switch ...Chevy silverado 2006 4.3 stalling Codes p0118 p0174 p0171 - Answered by a verified GM Mechanic. We use cookies to give you the best possible experience on our website. ... 2004 GMC Sierra 1500 4.8L got P0171 and P0174 codes, Changed MAF Sensor, checked fuel pressure 60 psi.Customer: 2003 Chevy Silverado CK Engine Code P0171 and P0174 THIS IS A FUEL SYSTEM LEAN BANK 1 AND 2 WHAT IS THE FIX FOR THIS TROUBLE CODES. Specialities include: Dog Veterinary, Cat Veterinary, Bird Veterinary, Large Animal Veterinary, Small Animal Veterinary. Thanks for using Just Answer.How to fixes a Chevy Silverado 5.3L engine with a P0171 Code System Too Lean (Bank 1)Read here for more information: https://www.backyardmechanic.org/fixes-f...Alternatively, intake and exhaust leaks can also throw off your trims leading to such codes. Did you used to get 15 mpg with E85? 2009 GMC Yukon XL SLT 5.3 K5L - 2012 GMC Sierra SLT 6.2 NHT - 2013 GMC Sierra SLT 6.2 GAT. “Woe unto them that call evil good, and good evil; that put darkness for light, and light for darkness; that put bitter for ...Fixing a Code P0174 on a 2002 Chevrolet Silverado with Ron Bilyeu - YouTube. AVI ON DEMAND. 14K subscribers. Subscribed. 150. 27K views 4 years ago. …The P0174 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0174 is set in along with the …Cw303. P0171 and p0174 are left side and right side lean codes. You either have a vaccum leak or lack of fuel throwing off your mixture settings your maf sensor can have something to do with this but throwing a fuel pressure gauge on when ts running might some some problems. I had the same codes and in turned out my fuel pressure was …If rough idle (I also got P0300, with P0171, P0174 codes) 1. Check the fuel pressure regulator on the drivers side fuel rail by pulling the vacuum line off. (It is bad if wet with fuel) 2. Check EGR valve is working properly, gasket is good, and the tubes don't have a leak with carb cleaner.#1 · Dec 14, 2023. Been getting occasional P0171, P0174 codes but the truck (07-13 Silverado 1500) runs great, idles great and is otherwise not having any performance …Codes P0171 & P0174. Tags 5.3 engine p0171 p0174 stalling. ... A forum community dedicated to Chevrolet Silverado and GMC Sierra pickup owners and enthusiasts. Come ...I had posted on December the 1st in anothers post that I also got the P0171 and P0174 codes, both banks lean. Cold Weather Probs ... Chevy Silverado and GMC Sierra Forum. A forum community dedicated to Chevrolet Silverado and GMC Sierra pickup owners and enthusiasts. Come join the discussion about performance, …The P0171 and P0174 are pointing to both banks running "lean". This means there is too much air or not enough fuel in the fuel/air mixture. When these codes are set together, there are a few different things that can cause this issue. First- a fuel pressure reading should be taken to ensure the fuel pump is working at normal capacity.p0101, p0171, p0174. I picked up this 04 silverado 1500 4x4 a few weeks ago. CEL is on and giving me those three codes. I replaced intake manifold gasket and cleaned MAF. Everything looks good and as far as I can tell all hoses between MAF and engine look great. Anyway, I cleared the codes and they popped up about two days later.2012 6.0 vortec gas. p0174 right bank code. ... well, hauling my 67 gran prix to day, the above code came up, pulled into auto zone for diagnosis. as usual, could be anyone of 6 things, so, further researching led me to mass airflow sensor, or o2 sensor as the more usual culprit,, ... A forum community dedicated to Chevrolet Silverado and …Oxygen Sensor – The P0175 code is thrown when the B2S1 O2 sensor does not register the right amount of oxygen in the exhaust. The computer will still adjust the air/fuel mixture to compensate. A bad O2 sensor will show a lean mixture more often, though. Mass Air Flow Sensor – Your Silverado’s mass air flow sensor calculates the …2004 TB EXT, 5.3 L. The last couple of winters, when the outside air is cold, would throw the P0171, but I never noticed any change in performance, and it would not throw a code on warm days, so I ignored it. This winter, about four times has gone into REP mode. After the first time, I cleaned the MAF sensor—would still throw the P0171 on ...Chevrolet is an American icon, known for the Camaro, Corvette, Malibu, Impala and more. Take this quiz to see if you can recognize the most memorable '70s Chevys! Advertisement Adv...#1 · Dec 14, 2023. Been getting occasional P0171, P0174 codes but the truck (07-13 Silverado 1500) runs great, idles great and is otherwise not having any performance …The P0174 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0174 is set in along with the P0171 code, it is highly likely that the problem is caused by an intake leak. If there are no intake leaks, the next step is to replace the air filter and clean the Mass Air Flow (MAF) Sensor.A Code P0174.....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 …Jan 2, 2019 ... 1999 Chevy S10 Pickup 4.3 Customer complaint is low power and the check engine light is on. Understanding ST and LT Fuel trim was the key to ...The P0174 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0174 is set in along with the …
May 2, 2022 ... 1997 Chevrolet Suburban (Lean codes P0171/P0174) ... System Too Lean - Code P0171 or P0174 on Your Car or Truck ... P0171and P0174 CODES CHEVY VORTEC .... Paulineanndv
I have a 2004 Silverado Z71, 5.3 with 154K miles. Other than this problem the ruck runs great. I had the fuel lines and fuel pump replaced two months ago and after that, I started to get the P0171 and P0174 (bank 1 and 2 lean) and the long term fuel trims "LTFT" are 18-25% (both) There were no signs of issues cold or warm.Dec 16, 2008. #1. I have a 2002 Avalanche 1500 with 90,000 miles. Mods include KN filter, Hypertech Power Programmer. Lately the truck has been running VERY rough, throwing the P0171, P0174 and P0300 codes, being way down on power and getting terrible mileage. After doing extensive research here, I checked the O2 sensors, injectors, and did a ...These are estimated costs to Fix p0175 Chevy Silverado: Vacuum leak- $100-$200. Air-fuel sensor/ Oxygen sensor- $200-$300. Repairing the exhaust- $100-$200. Fuel pressure regulator- $200-$400. Fuel pump- $1300-$1700. Cleaning the mass air flow sensor- $100. Replacing the mass air flow sensor- $300.Feb 25, 2023 ... Comments4 ; p0171 and p0174. James Davis · 54K views ; Check Engine Light? System Too Lean - Code P0171 or P0174 on Your Car or Truck. 1A Auto: ...Oxygen Sensor – The P0175 code is thrown when the B2S1 O2 sensor does not register the right amount of oxygen in the exhaust. The computer will still adjust the air/fuel mixture to compensate. A bad O2 sensor will show a lean mixture more often, though. Mass Air Flow Sensor – Your Silverado’s mass air flow sensor calculates the …The P0174 code means that the O2 sensor on bank 2 has recognized a too lean mixture, and the imbalance is too great for the O2 sensor to correct the issue on its …8 posts · Joined 2024. #1 · Mar 1, 2024. Hello, 2004, 2500HD, 6.0L, 4X4 with 131,000 miles all original no after market modes. I have P0171 and P0174 codes. My effort. New -. Fuel Tank Pressure Sensor, Gas Cap,Canister Purge Valve, Evap canister vent solenoid, fuel pump (55psi running), Mass flow sensor, air filter. Basically every item new ...That means that the passenger side was showing lean quite possibly from an exhaust leak, loose O2 sensor, or other problem. I would scan it to ...Meet the Experts. 2018 Silverado 6.0 2500hd p0171 p0174 codes. truck has 1250. miles on it. Codes are p0171 and p0174. i did reset but - Answered by a verified Chevy Mechanic.Jan 3, 2013 · If anyone's ever corrected the P0171/P0174 codes, please speak up! Save Share. Like. T. ... Chevy Silverado and GMC Sierra Forum. 1.4M posts 182.9K members P0174 Diagnosis. To diagnose P0174, a mechanic will typically use an OBD-II scanner or code reader to check for fault codes, and then perform a visual inspection of the engine, fuel system, air intake system, and exhaust system..