Fuel System Archives - Page 4 of 12 - UnderhoodService
Fuel System FAQ

How do I test the wiring for the fuel pump on a vehicle? What are the symptoms of a clogged fuel filter? What are the signs of E85 contamination? What should I do when I install the new pump and it doesn’t work? Get the answers to these questions and more in this Fuel System FAQ.

BMW Fuel System Repair Essentials

The BMW N54 fuel pump recall a few years ago brought to light the importance of the integrity of the fuel system and how it can contribute to the overall reliability of a vehicle. These fuel quality issues apply to all BMW vehicles with either port or direct injection. The underlying message here is that if the cleanliness and overall integrity of the fuel tank is ignored, it will damage any fuel pump. This is why addressing the fuel tank is essential during any pump replacement to prevent costly comebacks that can also hurt your reputation.

Toyota Tech Tip: Rough Idle, Surging Between 500 To 800 RPM

The owner of 2005 Toyota Avalon complains check engine light is on, rough idle and engine idle surging between 500 and 800 rpm. The technician retrieved Diagnostic Trouble Code (DTC) P0171 and P0174 (System too lean banks 1 and 2). The technician replaced the air fuel sensors on both banks and cleared DTCs. After driving vehicle for approximately one mile, all symptoms returned.

Diagnostic Dilemma: 1999 Dodge Dakota Intermittent Stall Complaints

Diagnosing intermittent stalling complaints is a challenging experience for any diagnostic technician because any number of electrical and mechanical failures can cause an engine to intermittently stall. Most of us immediately narrow this laundry list of potential failures down to the most common few, which include components like the crankshaft position sensor and electric fuel pump.

Diagnosing EGR And Secondary Air Systems

The perfect internal combustion vehicle would be able to put the exact amount of fuel and air into the combustion chamber. If the perfect combustion event happened, you would get nothing more than water and carbon dioxide. We are not there yet. In the mean time, we have exhaust gas recirculation systems (EGR), secondary air injection and catalytic converters.

Air Filter Fuel Trim Diagnostics

The modern engine measures two things extremely well, the amount of air going into the combustion chamber with the mass airflow sensor (MAF), and the byproducts that are generated by the combustion event with the oxygen sensor. These measurements allow the engine’s computer to put the right amount of fuel and spark into the cylinder to give the most efficient and cleanest combustion event.

Thumping Noise At Cold Start On Honda Accord

Honda Accord owners may report a thump as the ignition switch is released from the start position or as the engine starts. This noise sounds similar to a rubber mallet striking the frame and occurs only on a cold start (the vehicle has been sitting for some time, usually overnight).

How Does The EGR And Secondary Air Injection Work With The Catalytic Converter?

The perfect internal combustion vehicle would be able to put the exact amount of fuel and air into the combustion chamber. If the perfect combustion event happened, you would get nothing more than water and carbon dioxide. There would not be any unburned fuel or oxygen. What would be needed to make this happen? Direct injection into the combustion chamber is a good start. You would also need the perfect combustion chamber free from hot spots – areas of unwanted turbulence or carbon build up. In the mean time, we have exhaust gas recirculation systems (EGR), secondary air injection and catalytic converters to reduce emissions

Why A Clean Fuel Tank Is Important For A Fuel Pump’s Diet

Fuel pump replacement comebacks can be costly and can hurt your reputation. One of the leading causes of failure is the tank. If a vehicle gets 20 miles to the gallon, then more than 5,000 gallons of gas (from many stations) will go through the tank in 100,000 miles. During this time, sediment, rust and debris from the pump can find its way into the tank. Removing all contaminates is critical.

Explorer/Mountaineer Fuel Pump Tech Tip

Some 2004-’07 Explorer four door/Mountaineer vehicles may exhibit the malfunction indicator lamp (MIL) on with diagnostic trouble code (DTC) P0463 or an erratic fuel gauge concern. This could be from sulphur contamination in the fuel, causing an open or high resistance on the fuel sender card.

Diagnostic Solutions: Direct Fuel Injection Systems

For veteran technicians, it’s no wonder that the internal combustion engine (ICE) has been pronounced “dead” on more than one occasion. After having gone through the gas turbine craze during the early 1960s and the rotary engine fad of the 1970s, it comes as no surprise that we’re witnessing still another resurrection of the reciprocating internal combustion engine in the form of gasoline direct fuel injection.

Spectra Premium Announces Fuel Delivery Lifetime Warranty

Spectra Premium Industries has announced a limited lifetime warranty on its fuel pump assemblies, electrical and mechanical fuel pumps and fuel strainers, effective Jan. 1, 2014.