Jaguar S-Type, fuel algae

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I have been running my Jaguar S-TYPE for three-and-a-half years and have been plagued with fuel starvation symptoms. On start up, the engine runs fine until it reaches normal operating temperature, then it starts showing signs of fuel starvation. In the early stages it appeared to be linked to the amount of fuel in the tank, so I kept it above a quarter-tank full. Then the problem gradually got worse and eventually it would hesitate even with a full fuel tank. Also I would occasionally hear a noise that seemed to come from the rear of the car – the fuel tank area. By this point, I was reasonably sure the problem was the fuel pump in the fuel tank and a secondhand in-tank fuel pump cured the problem. It seem that the in-tank fuel pump would work normally for about the same length of time it took for the engine to reach normal working temperature, then I assume the actual fuel pump would heat up, causing part of the pump to expand and start touching the outer case. Then the fuel pump would start to run sporadically. Another point: have you had any reports of algae growing in the diesel filter?aqaqaq
Michael Polglase

The term ‘diesel fuel algae’ is widely used, but the substance is not actually algae. The substance normally found in the fuel filter is made up of polymer, asphalt and wax residues. One of the most common causes of this is using summer diesel in the winter and often occurs in low-mileage vehicles that have retained a tank of fuel for a long period of time. Summer diesel contains more wax, which crystallises in colder weather and blocks the filter. Another cause of is the biodegradation of the fuel, which also causes the filter to become blocked. There is another cause more usually associated with marine diesel engines and this is water contamination. In the marine field, a product called Diesel Bug Treatment is commonly used to prevent or eradicate fuel spoilage organisms in the system. It is sold at this website Although designed primarily for marine engines, it can safely be used in any diesel engine.

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