Fuel pump relay is on 330D?

[Zead]

Anyone know where the fuel pump relay is on E46 330D? 52 plate. I have been told before it's behind the glove box. My indi has assured me in the past he has checked them, but didn't tell me where they were. The only thing I can find is the fuse box and a large multi-connector above that.

Baffled Z

[fixedwheelnut]

Once you drop the glovebox lid off, undo the screws that hold up the frame and remove it.
Once that is off you will see a row of relays above the fuse box, it will be one of the pale green ones, look for the main feed wire for the fuel pump usually white with a blue stripe.

[BlackSpider]

[quote=fixedwheelnut] Once you drop the glovebox lid off.

Much easier to leave lid on and just remove screws...give it a go ;-).
Are you taking Seniors any time soon?

The relays for the pump tend to burn on the contact-not always obvious unless the green cap is removed and the contacts physically checked.

Edited by BlackSpider on Saturday 29th December 22:31

[Zead]

thanks guys, will have a go at first light

Z

[fixedwheelnut]

BlackSpider said:

fixedwheelnut said:

Once you drop the glovebox lid off.

Much easier to leave lid on and just remove screws...give it a go ;-).
Are you taking Seniors any time soon?

The relays for the pump tend to burn on the contact-not always obvious unless the green cap is removed and the contacts physically checked.

Edited by BlackSpider on Saturday 29th December 22:31

Did it in April earlier this year after putting it off a couple of years while my mum was ill.

Edited by fixedwheelnut on Monday 31st December 02:15

[Zead]

job done, but relay was fine. Any experience of Pressure sensor on main fuel rail failing? Other than that it must be the pre-supply pump

[The_Doc]

Zead said:

job done, but relay was fine. Any experience of Pressure sensor on main fuel rail failing? Other than that it must be the pre-supply pump

both these things happened to me (over ~40k miles)

PM me with your car symptoms (or forum post) I've had both successfully fixed in Yorkshire.

All can fail, pre-supply pump is under passenger footwell (£220), pressure sensor gives a fault code on diagnostic and put my car into safe mode whilst driving.(£50)
Fuel pump relay eventually went about 1 month ago, and whilst dificult to diagnose, it only costs £5.

Will.

[Zead]

Hi Will

Car always starts from cold. A few times after a short journey, it doesn't restart. I cant hear pre-supply pump. Turning ign on/off 'til I hear pump, then it starts. Sometimes, esp on motorway, it has no acceleration. It stops a 2K rpm but slowly rises and will still cruise at illegal speeds.

Other times it will accelerate rapidly to 4K but then misfires. I had the same problem exactly a year ago. I had Maf and oil breather changed. Initially it didn't seem to cure problem, but then it just stopped and has been fine all year including a trip to Italy. I did post this problem then and a Blackspider posted a few possible causes.

Did your prices include fitting. I am happy to fix myself. I had pre-supply pump cover off and it looks straight forward, providing I dont need to empty tank. But I dont know where pressure sensor goes.

Thanks for the info. Colin

[The_Doc]

Zead said:

Hi Will

Car always starts from cold. A few times after a short journey, it doesn't restart. I cant hear pre-supply pump. Turning ign on/off 'til I hear pump, then it starts. Sometimes, esp on motorway, it has no acceleration. It stops a 2K rpm but slowly rises and will still cruise at illegal speeds.

Other times it will accelerate rapidly to 4K but then misfires. I had the same problem exactly a year ago. I had Maf and oil breather changed. Initially it didn't seem to cure problem, but then it just stopped and has been fine all year including a trip to Italy. I did post this problem then and a Blackspider posted a few possible causes.

Did your prices include fitting. I am happy to fix myself. I had pre-supply pump cover off and it looks straight forward, providing I dont need to empty tank. But I dont know where pressure sensor goes.

Thanks for the info. Colin

Mixed symptoms there with a bit of everything.

1)Won't rev above 2k on motorway, slow rise. This is how my car defaulted to safe mode when the pressure sensor went. Garage found code in 5 mins
2)Won't start and you can't hear the fuel pump until you try multiple times with ignition-turn, then for no reason it starts. This is how my fuel pump relay failure was, until it failed fully (as did any starting)

My recommendation is find a local indie to get diagnostic done. Questions remain: Are there any fault codes? Does changing the relay(s) help? Can they give you a diagnosis, for you to then do the work.

My prices were including fitting at my trusted indie (£48/hr) with him taking up to, but no more than, 1/2 hour for each job, including replacing the inline fuel pump. I think its all easy work if you're inclined. You don't need to empty the tank for pump change, just mind air trapping.

Will.

[Zead]

It's looking likely to be one or both. The relay contacts looked fine, but for £5 it's worth changing. I suppose the real question is, does the sensor, thinking there is good pressure at rail, control the pre-supply pump. ie turns it off to prevent too much pressure when there is actually not enough. Logic and money says, change the sensor, if fault still present, change pump. My indi is in Spain for 2 weeks! and I don't trust anyone else.

Thanks once again.

[jcas]

Are there any spare relays for the fuel pump? My 330d currently won't start at all (ran fine one day, didn't start the next, turns over but wont start) and I am waiting to borrow a code reader, so just looking for easy things to check in the meanwhile.

James

[Zead]

The green ones are the same, no spares supplied though, but I don't know for sure, what the others control. I would only guess which is bad advice. But if you pop the cap off fuel pump relay, and check the contact for burning it may give you the answer. Run a needle file across it, and see if it helps.

Z

[BlackSpider]

When you get the fault memory read out,if it says rail pressure too low on start up it will be (likely be) injector runoff too high-failure within injector.
If it says pre supply pressure then fuel pump relay or inline pump under floor.

[adam s]

Bit of a thread revival!

I think my relay has gone judging by whats been said on here. I've located where they are but I could get my hands in there to get the relay out. Any tips? I tried removing brckets etc but couldn't really do it.

Thanks

[The_Doc]

garage did it

sorry.

[Zead]

hey, it's my thread. You have to remove the whole glove box and then lift the fuse panel out. This will give you the room to get in. There is a tool in fuse box to pull the relay. I cant remember which relay but you'll know when the pump stops whirring. It's green.

[adam s]

Thanks for the tip. I checked all of the relays and they are fine. Looking like the fuel pump ist kaput.
Think i'll just send her off to the indy.

Cheers

[Zead]

mine ended up being the fuel pump under the passenger seat. Easy to change, if you are happy lying on your back with diesel running down your sleeve. Pumps are about £140. Did mine in half an hour. + clearing my pit to make it easier

[adam s]

Think i'll let my man do it. Needs an MOT too so might as well.
I'll post back when I find out what the problem is.

Thanks

[DJFish]

Mine went around 60k
First the relay burned out, BMW chappie said the pump would most likely follow.
Pump went a week later and was promptly sorted by BMW Assist.
Apparently they all do that.

Shortly after that the undertray covering the fuel pump dropped off the car whilst driving.
The screws and clips can corrode so if you're replacing the fuel pump it may be worth replacing the clips as well.