x5 fuelsystem question

[willnc]

hi guys i am willnc from south africa the nc stands for norther cape the region i live in. i own a 2004 x5 30d, my first quest is about the fuel system on the x5.we cant seem to get enough fuel pressure at the injectors.the x5 was running fine untill i lifted the front end, the allarm went off,bmw reprogrammed the key and checked the x5 on their computer.the starter turns,it some times starts for a few seconds and die.if anyone have some information,diagrams for the fuel system, where and what to check.

[supersteve]

Check your codes. It sounds as though your MAF sensor may be going or you air intake tube maybe loose. On 4.4 ltr it should have 50 PSI @ the fuel rail while running. I'm not sure about the 3.0 ltr

[Laurence]

Originally Posted by willnc

hi guys i am willnc from south africa the nc stands for norther cape the region i live in. i own a 2004 x5 30d, my first quest is about the fuel system on the x5.we cant seem to get enough fuel pressure at the injectors.the x5 was running fine untill i lifted the front end, the allarm went off,bmw reprogrammed the key and checked the x5 on their computer.the starter turns,it some times starts for a few seconds and die.if anyone have some information,diagrams for the fuel system, where and what to check.

I had a similar problem with my Diesel (although nothing to do with lifting the front end - the problem happened for no apparent reason)
The issue I had was that the car wouldn't start. I had been using all day, parked at the shops, came out and ... nothing. It would turn over but not start.

To cut a very long story short...tha car was towed to the local dealer who had it in for a week trying to sort the problem.
It turned out that the fuel rail sensor was faulty - this was after the dealer replaced the fuel pump and three injectors

I can only assume that the fuel rail sensor was sending duff information to the ECU - its possible that if the sensor was reporting the fuel rail as high/low, the ECU would not let the engine fire up.

I hope this helps, let us know how you get on.

[supersteve]

As far as I know, the 4.4 and the 3.0 do not have fuel rail pressure sensors

[willnc]

hi guys my 30 diesels fuel rail pressure sensor have been replaced by local bmw.they think it might be dme box.the box is very expensive (no motorplan)would rather be sure.i have sent the dme,ews and the key for testing on other x5,might be an aligning problem between boxes(according to technician)

[vinuneuro]

Things to test/replace:

Fuel Filter
Fuel Pressure Regulator
Fuel Pump

As far as the DME goes, try swapping one in from a working X5 to see if that solves the problem. Better to find out this way before replacing a correctly functioning part.

[supersteve]

Originally Posted by supersteve

As far as I know, the 4.4 and the 3.0 do not have fuel rail pressure sensors

My bad. Though you where talking about a gas burner. Before replacing anything, test the fuel rail pressure. Make sure it is up to snuff.