2500 Silverado hard starting when cold
Asked by Rhesamc May 23, 2017 at 03:25 PM about the 2001 Chevrolet Silverado 2500HD LB 4WD
Question type: Maintenance & Repair
When it is cold it doesn't like to start. When it does it runs fine. Fuel pressure
is 50 psi and holds there for at least 10 minutes. it drops about 10 psi when
running. Scanner says "fuel volume regulator control circuit open". I have no
idea what it means. I've replaced fuel pressure regulator, no change. I think
it may be electrical?
5 Answers
The fuel volume regulator code may have several causes: Disconnected plug to the fuel regulator Possible corrosion in the sensor connector Damage to the sensor wiring to the ECM Leaking fuel pressure regulator Damaged fuel pump The ECM is damaged
What are your driving symptoms? likely affect would be: 1.The engine’s performance during driving 2. Possible stalling 3. It may cause the exhaust to show smoke in various colors from black to white 4. Fuel economy will not be efficient
Just replacing the fuel pressure regulator never guarantees a successful repair in resolving your issue. It may be caused by several components as listed above and more. Performing a visual inspection and testing the car with a scan tool, and other special equipment listed above, will verify your issue before spending money and time replacing the fuel pressure regulator unnecessarily. Electrical signals require evaluation by a scan tool and voltage meter to ensure that the fuel pressure regulator requires replacement or if another problem exists. Additional testing may be required.
Lastly, any sensor issue may occur all the time or intermittently. Some fault codes may require more time to diagnose. With this particular code, the solution could be simple or require extensive time to diagnose and repair. Depending on your vehicle, it may take several hours to determine the root cause and repair. I have experienced this code in the past mostly on Ford vehicles. After using a scan tool and monitoring the voltage, I could determine if the fuel pressure regulator, wiring, ECM, or fuel pump is at fault. With the scan tool connected I typically evaluate the data while checking the fuel pressure and using a voltage meter to ensure all the values match. If the values do not match, then a further diagnosis is required. The sensor may be the cause, wiring issues might be burning/rubbing on another engine component from previous repairs, rodents like to chew wires, or you may have a bad ECM. A scan tool inspection is required. Then we will determine where the fault lies. We could clear the fault code/light first, then verify if the Check Engine Light returns, and go from there. It may have been a weird occurrence from bad gas or weather, or a permanent problem. Vehicles with high mileage (over 80,000 miles) may just need a regulator. But replacing parts based upon a code is not recommended
Bottom line ...items to check 1.Disconnected plug to the fuel regulator 2.Possible corrosion in the sensor connector 3.Damage to the sensor wiring to the ECM 4.Leaking fuel pressure regulator 5.Damaged fuel pump The ECM is damaged