Our latest featured service is fuel pump replacement on a 2006 Range Rover, brought to us by a client from Dunbar, Vancouver.
This Range Rover arrived at our shop by tow truck following a conversation with our client. He called explaining that his engine was cranking over but would not start. I explained to him that towing the vehicle to the shop was really all that we could offer. This is the case with most modern cars: due to their complexity there is little that one can do on the roadside, though sometimes you get lucky. On a positive note, modern cars break down rarely when compared to cars of the past.
After the vehicle arrived we diagnosed the concern. There are 3 basic things required to make an internal combustion gasoline engine run, assuming of course that the starter is turning the engine over: these are: compression, spark and fuel.
Based on experience we can usually get a pretty good idea of engine compression just by listening to the engine cranking over. In the case of this Range Rover it sounded good.
Next tests were for spark, fuel injector pulse and fuel pressure. Spark and injector pulse were good.
Fuel pressure is tested by connected a fuel pressure gauge to the engine. Here we found no fuel pressure and this was why the engine failed to run.
At this point we were left with a few more tests to see if the pump was dead or there was a wiring or electronic issue present causing the pump not to run.
We verified that all things electrical were good and the pump was dead.
Replacing the fuel pump on this Range Rover is timing consuming due to the use of a saddle tank which incorporates two fuel pickups and gauge sending units. Fortunately the access is under the rear seat which makes the job a little easier.
Fuel pumps on almost all vehicles are located inside the fuel tank. There are several reasons for this: ease of manufacturing being one; the other is a performance advantage to having the pump at the source of the liquid instead of it having to suck the fuel from the tank. This is more efficient and uses less energy
The disadvantage is in the access. As I mentioned this Range Rover is easier due to in car access. Many cars are not so easy: you must remove the fuel tank to change the pump.
Should you ever experience your engine cranking over and not starting like this Range Rover did I can offer a couple of tips to you. Be sure to check your fuel gauge. On more than a few occasions we’ve had vehicles towed in with a possible fuel pump concern only to find the tank is empty. How might you know if it is your fuel pump? On most cars when you turn your key to start the fuel pump will run for a couple of seconds and if you listen closely to the underside of your vehicle you can hear a faint humming sound. It can be tricky to hear this but if you can, and you even suspect that you are low on fuel you might be best to get a Jerry can and a few liters of fuel into the tank: it might save you an expensive tow and diagnosis.
One other tip about fuel pumps, and this applies to all cars and light trucks: don’t run your vehicle low on fuel: the moment the low fuel warning light comes on, fill up your tank. Adhering to this will maximize the life of your fuel pump.
For more information about fuel pumps click this link https://en.wikipedia.org/wiki/Fuel_pump
For more information on the Range Rover click here https://en.wikipedia.org/wiki/Range_Rover