Hummer H1 P0456: Meaning, Causes, How to Fix

One of the most common trouble codes with the Hummer H1 is the P0456 code. This trouble code references a number that is given to you when you plug your H1 into an OBDII scanner. P0456 Indicates that there is a small leak in the evaporative emission control system. It often appears with or is … Read more

Hummer H1 P0455: Meaning, Causes, + How to Fix

P0455 in the Hummer H1 is a trouble code that indicates your truck has a LARGE evaporative emissions leak. With this code, you shouldn’t notice any symptoms besides perhaps a noticeable fuel smell. P0455 usually is not an immediate threat to the driveability of your H1. But, whenever the check engine light is on, it’s … Read more

Hummer H1 P0341: CPS – Range/Performance

P0341 is a somewhat common OBDII diagnostic code in the Hummer H1. It means that there is a Range/Performance problem. In layman terms this means that there is a problem with the signal coming from the Camshaft Position Sensor (CPS).   OBDII P0341 means that there is a problem with the Camshaft Position Sensor (CPS) … Read more

Hummer H1 P0113: IAT Sensor → High Input Problem

P0113 is an OBDII trouble code that occurs when the Hummer H1′s engine management computer detects that there is an issue with the Intake Air Temperature (IAT) Sensor, specifically that there is a High Input Problem with it. P0113: IAT Sensor – High Input Problem The IAT sensor is responsible for measuring the air temperature … Read more

Hummer H1 P0325 Code: Causes + How to Fix

If you own a Hummer H1 and have recently encountered a P0325 trouble code, you may be wondering what it means and how to fix it. This article will explain the causes of this code and provide step-by-step instructions for resolving the issue. The knock sensor’s primary role is to detect and monitor any abnormal … Read more

Hummer H1 P0304: Cylinder 4 Misfire – Diagnosis + Fix

If your Hummer H1 has the P0304 trouble code, you should know that it’s about as common of a code as there is. It’s a generic OBD IIcode (same meaning for all vehicles) that indicates that your vehicle’s fourth cylinder is misfiring. P0304 is a drivability concern and should be dealt with right away. If … Read more

Hummer H1 P0449: Vent Valve Solenoid – Circuit Malfunction

A somewhat common issue with the Hummer H1 is the P0449 code. This code references a number that is given to you when you plug it into a OBD2 scanner. P0449 deals with the evaporative emissions control (EVAP) system. It often appears with, or is related other codes, such as P0420, P0446, and very often … Read more

Hummer H1 P0340 Code: Diagnosis, Causes, How to Fix

One of the more common engine management trouble codes that can occur in the Hummer H1 is P0340. It’s a generic code, which means it has the same definition for every car or truck made after 1996. P0340 is related to the camshaft position sensor and points to an issue with the wiring harness connected … Read more

P0303 Hummer H1: Cylinder 3 Misfire Diagnosis

If your Hummer H1 has the P0303 trouble code, you should know that it’s about as common of a code as there is. It’s a generic code (same meaning for all vehicles) that indicates that your vehicle’s third cylinder is misfiring. P0303 is a real drivability concern and should be dealt with right away. If … Read more