Independent Renault Forums banner

1 - 20 of 29 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #1
Hi all,
Another non starting post i'm afraid!
My wifes 03 scenic 1.9dci will not start, having now got hold of a haynes manual, i think i have isolated the problem to the electrical low pressure fuel pump, as the filter, and hence the high pressure pump seem not to have a diesel supply!
The haynes book has a picture of the pump on the "right hand side of the engine bay" Well i have followed the fuel lines from the filter and i simply cannot find it!
I have checked the designated 60A fuse and relay, and also swoped the smaller black (supposidly feeder relays) around just in case, but my only hope now is to find the ellusive pump and check electrics from there!
Any ideas !?
Cheers,
Ian.
 

·
Premium Member
Joined
·
43,291 Posts
Hi Megan - I'm not sure if your car even has a primary fuel pump (also known as a scavenge pump). The pump Haynes refers to is a hand priming pump (looks like a rubber bulb which you squeeze) close to the fuel filter (although not all models have them fitted.) According yo my Haynes manual the low pressure pump is incorporated in the high pressure pump.. If it is fitted with a primary pump these are usually accessed by lifting the rear seat and then via an inspection panel.
Asa matter of interest what happened to cause the problem - was it after running out of fuel or changing the filter:)
 

·
Registered
Joined
·
19 Posts
Discussion Starter #3
Hi neither, wife dropped son at school, then nothing!
she thinks there was a strange buzz from the front of the car when she switched off, but other than that all was normal.
The manual i have red front, shows a pic of a electric pump, and the description of the cdi supply as a 2 bar electric pump feeding the high pressure pump via the filter, which i my case is the sealed one with 5 pipes on it.
Cheers,
Ian.
 

·
Premium Member
Joined
·
43,291 Posts
Hi Megan - I've looked through a number of books I have but unfortuneately can't find anyting pertaining to your model. In my experience low pressure pumps are usually fitted in the fuel tank controlled via a relay activated by the ignition. Maybe the buzzing sound your wife heard was the relay trying to engage - in my experience relays buzz either because they are faulty or can't get a good earth - it may be worth checking a the earth connections to the battery or engine. Tank installed pumps are usually part and parcel of the fuel guage unit inserted into the fuel tank and accessed by lifting the back seat.:)
 

·
Registered
Joined
·
19 Posts
Discussion Starter #5
Thanks for that, as i say i cant find it in the engine bay so perhapse tank is next step!
It went to an independent garage yesterday, towed by the AA who said they tow started it and it seemed fine, we drove it home then within 30 mins non starting again. The garage used to look after my car, and didn't charge us for loking at it. It's just a pain to get it towed off if i can find a solution!
Cheers,
Ian.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #7
Hi,
thanks for the reply, it turns over, does everything normal, except start!
The only thing i know for sure so far is that there is no diesel getting to the filter, the pipes are colour coded, so i tried each input one at a time to check, and even with the engine turning over, no diesel supply.
Following an earlier reply from madnoel10, i phoned a couple of renault dealers and eventual got a parts guy who checked the car using its reg. He says that the electric pump is attached to the sender unit, so tank is the next stop!
I can only assume the car started on a tow because something started to work again, as i would it expect an air leak or something along those lines to be pretty constant in terms of fault characteristics.
The only real pointer i had originally to the other pump was a comment on another forum, explaining that the system we have is a self priming one.
I hope this makes sence to you all, as I am picking this up as i go along. It has been a long time since i delved into the mechanics of a car! When i used to tinker i could recognise most of the parts for a start! ;-)

Cheers,
Ian
 

·
Premium Member
Joined
·
43,291 Posts
Hi Megane - it seems afterall the low pressure pump is in the tank - if you lift the backseat you should hear it running if only for a short time when you put the ignition on. The pump is governed by a pressure switch - when you switch the isnition it should power up for a few seconds until the system reaches about 2 bar and then start up again when the negine starts to run. Some cars also have a built in circuit breaker which activates in the event of an accident - if fitted it will have a reset button.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #10
Update!
I can confirm that there is no pump at all in the fuel tank unit.
The low pressure pump is actually located on the drivers side of the engine compartment burried down babove the steering gaitor and the chassis member.
So now I have found it all i have to do is find a way of getting at it!
Stay tuned!
Cheers,
Ian.
 

·
Premium Member
Joined
·
116 Posts
Hello,

Before you mess with your pump, try the pressure switch.

As you know the pump runs when the ignition is turned on, then switches off. If the switch has failed in the pressurised position, it will never run.

I think the switch is somewhere near the high pressure pump on the engine block.

Best of luck

Murchin.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #12
Hi Murchin,
Thanks fpr the idea, I didn't know it has one!
I will certainly look for a switch, as i have now discovered that i cannot get the alloy wheel off to access the drivers side of the engine bay, thanks to some megga zellos guy with an air wrench at the tyre depot! (I have already snapped one of the locking wheel nut keys!)
I have found that if you switch the iginition on, and put your head by the wheel you can here a couple of rapid clicks, as if the pump is trying to kick in but cannot. By sqeezing under the car, (presently on the main road outside my hose!) You can just see the bottom of the pump, and a very green electrical connector. So possibly a naff connection due to water/salt ingress?
The saga continues!
Cheers,
Ian
 

·
Premium Member
Joined
·
43,291 Posts
The moral of the story here is tighten yor own wheelnuts if you can (torque them properly). Each time my car has been to the garage I loosen the wheel nuts and check them myself - then I know I''ll be able to get them off during a wet durty night on the motorway. During my 40 years experience with cars I have never heard of a car wheel falling off because it is too loose (loose wheels give you plenty of warning - they make a real scary noise). In the contrary I have heard of countless wheels parting company due to failed or broken wheel bolts due to overtightening where they has been stressed to the point of creating fatigue and fracture. Take the air-gun away from the tyre fitters I say.:)
 

·
Registered
Joined
·
19 Posts
Discussion Starter #14
Having already broken one of two locking keys, i tend to agree, even the use of an air ratchet, rated at some 250psi has failed to budge the thing, i am now faced with the joy of drilling the whole thing out, before i can even confirm my theory of a faulty low pressure pump!
And cure (or not) the original problem :-(
Cheers,
Ian.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #15
UPDATE:
Hi guys, having eventually got the wheel off, i was able to spend a "joyful" 2 hours getting the pump in to a position where i could test it. 12v directly onto motor, nothing!
1 hour and some choice language later pump is out and in my hand. With 12v across it is just sits there, but if you hit the body of the pump it works.
So off to the dealer on Monday to order the replacement pump!
Cheers,
Ian
 

·
Registered
Joined
·
19 Posts
Discussion Starter #17
It may be next weekend before i can obtain and fit the replacement pump, due to work commitments, but i will certainly report back.
It seems to me that this pump could be the cause of many a niggling problem on these Dci engines.
My test so far tends to show that once primed the main high pressure pump has enough "pull" to keep itself fed.
I am just wondering now if a problem we had a few months ago, when the idle speed seemed to "pulse" was the first signes of this pump failiure.
Stay tuned ;-)

Cheers,
Ian.
 

·
Premium Member
Joined
·
43,291 Posts
Your diagnosis may be correct as one of the reasons for self-bleeding pumps surging is the poor supply of fuel or drawing air. The buzzing sound was probably the low pressure pump throwing a tantrum. In my experience very few diesels cars have a priming pump (sometimes referred to as scavenger pump). Why not try this short-term solution - install a 25 litre drum on the roof and run a hose directly to the main fuel filter and let it gravity feed - only joking. You could tie the wife to the roof to hold it on:rofl: :rofl:
 

·
Registered
Joined
·
19 Posts
Discussion Starter #19
Nice one!
I have already threatened her with something along those lines :)

Seriously though, the positioning of the pump, just above and slightly backward of the steering assay on the drivers side is an absolute joke!
Cheers,
Ian.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #20
update!

Finally got around to fitting the relacement pump today.
Car now starts on the first turn of the key!
I have found the best method for removing the pump is to remove the two locating bolts that hold the pump bracket, one from behind the wheel arch, just to the front of the steering arm, the other from below, just rearward of the steering arm. Then by releasing the bottom fuel pipe, and the top electrical connector, the pump can be teased out from the wheel arch.
One problem i have now is erratic idle, engins searches between 800/1000rpm. Interestingly if you hold it at 1200rpm or above, (all as indicated by dash tacho), it stops searching!
There are no air bubles evident in the pipes, it has a new fuel filter, which seemed to prime easily with the new pump.
So any ideas welcome ;-)
If anyone else sufferes from the initial pump failiur I had, the part number for the relacement is;
8200639432. Cost, wait for it.. just shy of £200! Robbery!
Cheers,
Ian
 
1 - 20 of 29 Posts
Top