What does p0171 mean on a Chevy Silverado?
P0171 – Fuel Trim System Lean → Bank 1: P0171 indicates that the side of the engine with the first cylinder (Bank 1) is running lean. P0174- Fuel Trim System Lean → Bank 2: P0174 indicates that the side of the engine with the first cylinder (Bank 2) is running lean.
How to check fuel trim in GM p0171?
1. With engine at operating temperature, use a scan tool to check and record Long Term & Short Term fuel trims. 2. Shut off the engine. Then disconnect the foul air tube from the intake manifold as shown. Plug both sides 3. Start the engine and check Short Term & Long Term fuel trims.
What causes a GMC Yukon to have code p0174?
Here are the typical symptoms that something is wrong when your Yukon has codes P0174 and P0171. Fuel Mileage- may or may not suffer depending on how much the air fuel mixture has changed. Misfire – If the air fuel mixture has gotten too far from factory specs, this can cause the vehicle to misfire or run rough.
What causes a lean mixture on the p0171 code?
Intake leaks are a widespread problem when it comes to the P0171 code. Intake/Vacuum/boost pipe leaks can trick the MAF sensor and cause a lean mixture. The MAF sensor measures all air that is going into the engine and telling the engine control unit which amount of air it is.
What does the code p0171 mean on a GMC Sierra?
P0171 and P0174 both indicate that there is a lean condition present in your GMC Sierra. By themselves, these are some of the most common OBD2 codes. When they are together, it indicates that the entire engine is running lean. Both of these codes are generic, which means they have the same meaning (Sierra or not).
What is the lean bank code on a GMC Sierra?
The code is often accompanied by the P0174 code, which is for bank 2. P0171: Fuel Trim System Lean Bank 1 P0171 and P0174 GMC Sierra– If you have both of these codes at the same time, this is where you should start.
What causes GMC fuel trim system Lean Bank 1 p0171?
The P0171 code could also be caused may be caused by one or more of the following: debris on MAF sensor causing an incorrect reading, improper oil level, low or high fuel pressure or Engine Control Temperature (ECT) Sensor reading inaccurate. If playback doesn’t begin shortly, try restarting your device.
What are the trouble codes on my GMC Sierra?
Two of the most common trouble codes with the GMC Sierra are P0174 and P0171 . Both of these codes reference a number that is given to you when you plug your truck into a OBDII scanner. P0171 and P0174 occur when the air/fuel mixture on the truck gets too lean.