XSeries-forum

Hello everyone.

I've recently ran into a little snag with my X5, We had a leaking injector which we suspected was leaking from the copper seal. We proceed to dismantle the car. to get access, removed the pipes to the injector, connections etc managed to remove it replaced the rubber ring, and the copper washer (it seemed to be leaking from the top) so we tighted it back down as i seemed loose and then refit.

We did everything else, new glowplugs and a glowplug relay while we was there. anyway we refitted the intake manifold. got everything buttoned up.
I thought since we had the pipes off ill bleed the system via the diagnostics route. which we did a few times to be on the safe side.

We tried to fire it up, it would turn over, (pumps inline etc all working as they made noise while doing the bleeding)
but failed to start, we are thinking the injector we pulled is the one responsible. ideally we think it may be stuck open and not allowing the pressure too build to start

code we got 4b90 rail pressure monitoring rail pressure too low during startup
and a few glow plugs (guessing they either duff or covered in diesel )

anyone shed any idea on this?

currently trying to source a injector nearby (newcastle upon tyne) if anyone has one
haha

Kind Regards
Drew

Could be air still trapped in the system that’s causing a low pressure alarm. On line searches suggest the use of ISTA-D for the process.

Might sound daft, but are all the connectors fully home as well? It wouldn’t be the first time that an electrical connection got overlooked. Diesel is not a conductor so should not affect the function of the glowplugs. Note that you can’t mix Bosch control hardware & BERU plugs

X5Sport wrote: ↑Fri Apr 05, 2024 11:30 am Could be air still trapped in the system that’s causing a low pressure alarm.

Might sound daft, but are all the connectors fully home as well? It wouldn’t be the first time that an electrical connection got overlooked. Diesel is not a conductor so should not affect the function of the glowplugs. Note that you can’t mix Bosch control hardware & BERU plugs

Hello mate, cheers for the reply yeah we double checked the connections on everything (even to a point i was disconnecting checking for codes) in refrence, just making sure each one reported back.

in regards to the glowplug situation

We had a few dud glow plugs upon replacing the glow plug relay which was a (HITACHI) replacement part. most certainly worked but we had a couple codes come back which was bad glowplugs defo dead as we tested them, We was only able to get bosch glow plugs locally in there replacement cleared codes, and tried to fire (ironicly the ones that have come back ) are not the ones ive put in recently its the other ones. more then likely screwed. either way at the time the bmw didnt need them anyway was warm enough outside.

It was worth a check.

Try looking up the code on line and going through the suggestions there.

A ‘leak-off’ test will prove/disprove an injector (it might be a different one!).

Glow plugs won't be the Non starting issue, they don't need them til below freezing. A leak off test with bottles to each injector, or a smooth running test if you can get it going maybe using easy start, is the battery fully charged or even get a jump start to get max crank speed as it will help rail pressure be met.

As said it wont be the glows causeing a non start, you did keep turning it over for several minutes I presume?, it does take a while to fire up after youve removed an injector....battery has to be fully charged and you have to keep it turning over not stop and try again.....

Fire it up with a bit of sniff or brake cleaner should get the diesel through quicker.

To everyone who’s replied it’s running now ended up being the injector at fault, new one fitted and coded running spot on

Wondering if anyone can shed a light on something so it’s got 6x brand new Bosch glowplugs and a brand new hitachi relay from fleebay.. anyway all fitted codes cleared and didn’t come up, I had a flat battery this morning ( left a phone charger in ) for a canny bit and drained it dry oops! Anyway jumped it off another car, but we had a 1/4 bank of glow plug perm errors.. anyone think it’s just cause of the dead battery when I was attempting to fire it? ( pull battery clear codes that way ) or is there anything else I can check, just so when the winter does hit I don’t have issues

Kind regards

If the plugs do show an error after clearing then it needs further investigation. With an Ohmmeter check each plug is showing between 0.2 and 5 Ohms. If less than 0.2 = short circuit. If no resistance reading (infinity) = open circuit. In both cases the plug is faulty.

X5Sport wrote: ↑Thu Apr 11, 2024 7:32 pm If the plugs do show an error after clearing then it needs further investigation. With an Ohmmeter check each plug is showing between 0.2 and 5 Ohms. If less than 0.2 = short circuit. If no resistance reading (infinity) = open circuit. In both cases the plug is faulty.

So would there never be an issue with the wiring itself to the module ? As we had issues with the other glow plugs purchased brand new and then it re appeared

It’s possible, but the ‘usual’ issue is with the plugs or controller themselves. Wiring can be checked with a meter as well. If it shows any signs of damage then be suspicious.

Previous reports have been around plugs being replaced only for the controller to fail once they’ve been changed, but you’ve done both already.

The controller only has power (for the relay and plugs) and canbus to signal faults. The engine electronics (DDE) gets a signal for open/short in the plugs or a relay problem.

Did you check the voltage of the original ones.

Hello everyone
just adding a reply. Cars fine, injector was issue for start.
Glowplugs now also working. seemed a dead batttery brought up the codes. cleared charged and now no issues, tested in cold temp too. started marv. thanks for the help! probs going to need everyones help with another issue ive found, in a separate post!

kind regards