How to test/change fuel pump?

[jas1]

My car has an intermittent starting issue, just wanting to know how best to test the fuel pump, and also how to change it.
I'm guessing the pump is inside the fuel tank, will this need to be removed?

Cheers

 

[RalphyBMW]

The pump, filter and sender assembly is a single unit which is accessible from the car interior by lifting up and removing the drivers side rear seat base.

 

[Robo_#1]

Look under your rear passenger seats mate, you should see a small hole there thats used to diagnose fuel pump problems.

First thing is see if you can here it trying to turn over when you start. If its not then check the voltage going to it.

Mine went pop a while back but luckily it was still under warrenty (though it did leave me stuck at the side of the road and turned a 30min journey to a 6hour one home for my birthday!! :bat: )

 

[jas1]

Found that last nite but thought it was just the sender, I'll try the voltage tonight, should the pump buzzed everytime the ignition is turn on?
If there is no voltage is there a relay to check, or could it be an immobiliser problem?

 

[Ed...]

its hard to distinguish what it is when its electronics mate the fuel pump should show no current until the engine is started, if you have voltage testers it may be worthwhile belling it when the engine is on and off. Renault are nutorious for immobiliser problems . . . . even when there cars are parked up next to telephone masts they have mega problems as it scrambles the signal so much the car wont even start, especially in keyless cars.

I take it you have accessed the pump?

 

[jas1]

Here's a run down of what's happen-

1st time it wouldn't start I'd just finished work, so been left all day, it attempted to fire up then just turned over, still didn't run the next morning, a mate had a quick look, pulled out the big fuses n relays next to the battery, tried it n fire up, so thought it was just a corroded terminal

2 days later would start 1st thing in the morning, fiddled with fuses ect again this time nothing, but when I returned from work tried it n fired up

3rd time would run for a good 4 days, put a thread up on here and was suggested it could be the tdc sensor, so changed that but didn't start up straight away, maybe 4 hours later and tried again then fired up, so thought I'd sorted it

4th time did same as 2nd time

5th time I'd been out, popped back home left it for 10mins, jumped back in it, started got half way out the drive then the revs were at tick over but wouldn't rev, then 10 sec or so and cut, tried it again and the same happen, then nothing, and that's how it's been since Sunday

I havnt looked at the pump ect yet, was gona take a multi meter n a few tools home with me tonight

 

[Ed...]

oh my that could be a number of things where do I start. . . . .


have you had any form of fault codes/lights?

when you pulled the fuse which one was it?

have you tried replacing said fuse with a new 1? (it could be a faulty fuse)

does it make a noise when it doesnt fire? like a mechanical mmmmmm

what did the dash say when you had no throttle just idle on the 5th time?

answe those and ill throw some more at you and try and diagnose what i think it could be.

 

[jas1]

oh my that could be a number of things where do I start. . . . .


have you had any form of fault codes/lights?
No fault codes (tried obd reader also)
when you pulled the fuse which one was it?
Think there 4, pulled them all
have you tried replacing said fuse with a new 1? (it could be a faulty fuse)
Havnt replaced any
does it make a noise when it doesnt fire? like a mechanical mmmmmm
Don't think so, just turns over and no attempt at firing
what did the dash say when you had no throttle just idle on the 5th time?
NoThing other than normal
answe those and ill throw some more at you and try and diagnose what i think it could be.

Only thing out of the ordinary when I lock the car now after trying to start in I've heard either one long beep or 3 short ones not not sure if that's coz I took the battery lead off

 

[gaz]

This is the whole assembly.

You need to drop the tank to get that out, so that's drop exhaust, undo rear brake lines, drop tank. What a PITA. Its also £200 worth trade for that alone

 

[jas1]

Yeah new it was around 200 quid, which I don't mind paying so long as it is the pump that's gone

 

[Foxspeed]

to test the pump - check the pressure at the fuel rail - the system is a non return set up so you wont need any fancy equipment

 

[Robo_#1]

Mine was just like this, we thought it was they key playing up, do much so that Renault gave me a new key. Two weeks later i was driving down vthr road and thr pump just packed up altogether. As its been aid its real pita to sort cos of the exhaust etc being in the way and that hole being way to small to fit the assembly through.

 

[jas1]

Can anyone confirm what wire does what on the sender unit/pump. There's 4 wires on the block conecter, a thick black which is earth, 2 thin wires one reading 5v so guessing this is the fuel gauge, then a thick green wire, this is reading 12v when I turn over the engine, is this the pump wire? If so looks like problem solved

Cheers