X5 3.0d won't start

[wpoll]

First step is to go back and find out what the 20A fuse that blew feeds - something took out that fuse. Might pay to find out what.

Once you indicate which fuse it was, we might be able to track it back to the source of the issue. Maybe.

As a possible starting place, one of the 20A fuses in the e-box protects the turbo boost control solenoid, among other things...

https://www.newtis.info/tisv2/a/en/e...-relay/hGi84uB

If the solenoid is faulty (and even once took out the fuse) it might explain the loss of power. Fixed a similar issue recently on a mates Sportage diesel - in his case the vacuum from the electric solenoid was flakey. Sorted the solenoid and his low-end torque came back.

*edit* removed some confusing links I posted (lots of jumping from DDE 4.0 and DDE 5.0 in newtis diagrams).

BTW, just what exact year/model is your X5? :-)

[F1Pilot]

Thanks wpoll.

The fuse was the main one for the DDE I thought. I would have to go back into it and see to be sure.

The boost solenoid was swapped out works exactly the same. We also locked the turbo closed, it could build boost all the way to 25psi, but only with revs and it made no extra power down low.

The car is a 2004 X5 e53 3.0d (218hp).

[wpoll]

Originally Posted by F1Pilot

Thanks wpoll.

The fuse was the main one for the DDE I thought. I would have to go back into it and see to be sure.

The boost solenoid was swapped out works exactly the same. We also locked the turbo closed, it could build boost all the way to 25psi, but only with revs and it made no extra power down low.

The car is a 2004 X5 e53 3.0d (218hp).

This sounds like the "V" is missing in "VGT". More of a FGT.

So when you say you locked the turbo "closed", you mean you pushed the actuator rod in (towards the turbo). I guess that means the vanes move and aren't jammed with carbon etc.

Can you determine if the actuator is controlling the vanes during normal operation? You can test this with a vacuum pump to replace the solenoid-controlled vacuum. Not sure which way around the 3.0d is but I think it's normal to see vacuum on the actuator at low rpm and have the vacuum go away at higher RPM. Easy to replicate this with a hand vacuum pump. Might need a long-ish vacuum line if you want to road test it though!!

[F1Pilot]

Yes we put the vacuum directly to the actuator to hold the vanes in the "boost" position. This is one of the tests a diesel mech tries when troubleshooting. The vanes move nice and freely also.

So I don't think it is the vanes or the solenoid. Even with them forced closed, it is still very slow down low and we never see a hint of black smoke.

[F1Pilot]

Having a look at that link you posted, it looks like the "Hall effect sensor" is on that 20a fuse also. Could that cause this?
When it lost all boost and was VERY slow, it also made the engine exhaust note much louder.

[wpoll]

Originally Posted by F1Pilot

Having a look at that link you posted, it looks like the "Hall effect sensor" is on that 20a fuse also. Could that cause this?
When it lost all boost and was VERY slow, it also made the engine exhaust note much louder.

Without knowing which exact 20A fuse blew, I can't be certain about the hall effect sensor (cam shaft position sensor). There are a good number of other possibilities...


F1 20A
B2381 Rail pressure control valve
B2382 Volume control valve
B2264 Solenoid valve, supercharger control (already eliminated)
B6219 Hall-effect sensor, camshaft 1
B6217 Hot-film air mass meter (eliminated?)

F2 20A
A2402 Preheating control unit
B2231 Electrical changeover valve, engine mount (whatever next!?)
B2244 Changeover valve for exhaust gas recirculation (AGR) (do they mean EGR?)

EGR or Rail pressure control seem possible, although I can't see why an issue here would increase engine noise much...

[F1Pilot]

Well it can't be EGR. I have a bypass fitted but also kept the solenoid connected electricaly to avoid any codes.

Couldn't believe it, but today the car has now destroyed a vibration damper (main pulley). Managed to get it home with the A/C turned off. Wondering if this is what was causing what felt like misfires.

Once I get this new problem fixed, I will get INPA working whilst driving to watch rail pressure and low fuel pressures.

[wpoll]

Originally Posted by F1Pilot

Well it can't be EGR. I have a bypass fitted but also kept the solenoid connected electricaly to avoid any codes.

Couldn't believe it, but today the car has now destroyed a vibration damper (main pulley). Managed to get it home with the A/C turned off. Wondering if this is what was causing what felt like misfires.

Once I get this new problem fixed, I will get INPA working whilst driving to watch rail pressure and low fuel pressures.

Dang... it never rains...

The vibration dampener thing seems to happen more in hot climates - not seen one fail down this way or hear much about them from the UK folk either.

Good luck with checking the rail pressures - it would be my next step too. I checked the rail pressures etc. while driving on the Sportage I was working on for my mate. Didn't show anything odd which is why I moved on to looking at the VGT system. Got lucky I think!

[andrewwynn]

you replaced the regulators but how about the fuel pump? you said it yourself 'it feels like fuel delivery problem'.

I had a fuel delivery problem on wife's gas 3.0i; it was a worn out (weak) pump; in her case the return line from the pres-regulator wasn't supplying enough flow back to the low side of the tank (left side) to siphon gas over to the surge tank where the pump is located. A weak pump would allow most operations besides WOT to seem normal but under solid demand of fuel, it would not supply the requested amount. I'm not sure about the diesel model but it's an 'urban legend' that the fuel filter need ever be replaced on the gas models they are lifetime design; if it seems like a filter problem it's more likely a pump problem (for gas models)

I'm not sure how long diesel fuel pumps last but gasoline pumps last 5000-7000 hours; divide your current odometer by the average speed reported by the dash computer and see a rough estimate of how many hours are on your pump.

Fuel pumps tend to die slowly where they just output less pressure at end-of-life and that can last a long time (years even). I bought my pump for $120 off eBay and though it is a 'copy cat' pump the design was lock-step with OEM with a 1 year warranty, i would buy the same pump again (in fact i surely will soon to replace my own since my car has 20,000 more miles than my wife's). I am pretty sure the diesel models use the same siphon pump solution, so a sure-fire way to know if the pump is worn out is if you can drive down to zero miles range. When the pump is failing, it won't supply enough return pressure from the pressure regulator to the siphon pump and the car will starve of fuel at perhaps an eighth of a tank of gas (could be a quarter). I strongly recommend people with x5 at least once or twice a year drive down to single digits (there is about a 15-20 mile reserve past zero FYI) to make sure their fuel pump is still working properly. If you 'run out of gas' at 10-20 miles (or in my case 70), your fuel pump is shot no doubt about it. It's an easy DIY to replace. It's an easy test to run; can you drive your car down to 0 miles to empty? If you can, more work is needed to find your problem, but if you 'run out of gas' at 20-30 miles range, your fuel pump is shot and likely the cause of your fuel delivery problem

[wpoll]

All good stuff anderewwynn but the diesel is a bit different....

The in-tank pump is similar (perhaps the same?) as is the siphon. The diesel then has another in-line electric pump right after the tank outlet, followed by the diesel fuel filter (which needs to be changed at least every third oil change or so). Then the fuel reaches the high-pressure pump on the engine.... And by high, I mean HIGH....

So there's a few "pumps" to check! But they do last a lot longer on diesels due to the better lubrication provided by diesel fuel. We call them "oil burners" for good reason. :-)

And we have to be very careful to avoid water in the fuel too, as that really damage the HP pump and injectors. Keeping the tank, lines, pumps etc. in good nick is critical on any diesel.