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My 2.5 2002 s type fuel pump is only getting 5 volts which isn't enough to start the car. The pump has had a 12 volt feed put on as a test and worked fine. I asked a Jaguar repairer about it and he said this was a known fault. The car has covered 150.000 miles, but only 40,000 on this pump, the first one lasting 110,000 miles. Has anyone experienced this and how was it repaired?

Thanks Foss 16

I've had the car fixed at Jagtech in Stockton. Discovered that there was a corroded terminal on the ECM. This then worked fine for 2 days, when the car wouldn't start. A jump start from a friends car proved that I also had a battery that wasn't charging, new battery fitted and everythings been ok. I had a momentary lapse in power on a long run, just for a few secopnds, but not sure if there's any connection. Since then the car has been great, but I'm still not fully confident in the car.

Still having problems. My wife said that it had cut out again at the traffic lights, but restarted again because of the new battery, then drove about 50 miles no problem. Wonder if there's an air flow sensor problem, that's just coming in intermittantly.

Throttle body problems as defined in my recent article are not unknown with S-types both V6 and V8 models which share a very similar throttle body. (BBA Reman at Rochester offer a recon service.) A fault with the body, sensors or throttle pedal will usually switch on the MIL lamp on the dash with an orange engine symbol. The MAF sensor located on the airflow meter located upstream of the air filter can become dirty. This is a hot wire unit. Clean with spray carb cleaner to remove the grot. Don`t touch the wire as it is VERY delicate.That is a five minute job with a small Torx bolt driver. Remove, clean and re install.

Many electrical problems are caused by corrosion points in multiplugs. I make a point of cleaning the most accessable ones from time to time and treat with a little electrical grease.

I`d suggest a scan with an Autologic unit or similar. Otherwise you are just chasing your tail to find a fault. I do believe that much of the electronics works on 5 volts, so don`t be suprised if when you meter out a circuit you find such readings.

Mike

Cheers Mike

will let the forum know of any successes

The problem with the fuel pump being a corroded wire, which was found by a local auto electrician costing £60 in total

Foss16

Excellent result, where would we be without local heroes like your Auto Electrician.