Intermittent starting

[Rickyd17]

Hi guys,

First post here and hoping someone can help. I've got a 2005 1.6 diesel Renault Megane. The last month or so it will sometimes start sometimes not. (Normally seems to start when it hasn't rained for a few days). I will list the things I have done and what result I got:
Changed all glow plugs - car ran perfect for 2 days
Fitted new glow plug relay - again car ran fine for 2-3 days.
Fitted new battery - car ran fine for a day
Cleaned EGR valve - no difference
Cleaned crankshaft sensor - car worked fine for a day
Checked fusebox for water (couldn't see any)

In addition to this over the last couple of years I've had 4 services, new fuel pump, new timing belt, new ECU, new wiring harness and new EGR valve. Car has only done 90k miles.

The car will start straight away if I jump it off another car. When it starts by itself it normally takes a little while and most of the time comes up with injector fault on the dash but then dissapears. In addition when I build up speed quite quick the injector light comes on again (normally around 3000 revs) but then goes after around 10 seconds.

Car runs fine when it's going (apart from the 3000 revs thing - but this doesn't seem to affect it when it's driving).

Sorry for the long post but I'm so stuck on what to do next! Any suggestions or help is greatly appreciated.

Thanks,

Ricky

[grandadbobby]

Hi,
you've done a lot on this, but you haven't mentioned any fault codes.
lf it's anything electrical or sensored, it should store a fault code.
lf you want to fix cars nowadays, you need a code reader.
lt's better than expensively stabbing in the dark, as l think you may have done.
The first time it helps you, it has more than paid for itself.
lf there's no codes, it'll be fuel related, even just air in the system.
Also, l would check the charging rate of the alternator.
Good luck
Bob

[Rickyd17]

Hi thanks for the reply, totally forgot to write on the fault codes I had. They were P0670 - glow plug control module - circuit malfunction, P0409 - EGR sensor A-circuit and P0089 Fuel pressure regulator - performance problem.

I haven't retried the code reader since I put on the new glow plug relay and cleaned the EGR (had to borrow one of my mate as I 'misplaced' mine) but I'll get it off him and try it tomorrow and see what it says.

Thanks for your help so far, never buying French again!!

[grandadbobby]

Of those codes, l would definately check connections to the fuel pressure reg.
Bob.

[Rickyd17]

Right so car wouldn't start wouldnt start this morning, had to jump it. Put the code reader in and got the exact same codes as previously mentioned, however they're all duplicated so it's coming up with 6 faults now??? It won't let me erase the codes either.
Anybody got any final ideas before I take the hit and spend about a million pounds at the garage?
I'm going to have a look at the fuel pressure regulator after work tonight but not really sure what I'm doing with it to be honest?

Again any help is greatly appreciated

[grandadbobby]

lf you can, check the connector and wiring to the pressure reg, and also undo an injector pipe to see if there's diesel pressure there.
lf there isn't, it's likely air is in the fuel system. lt just sounds to me, that when you jump start, it turns that bit quicker to provide enough fuel pressure.
The other thing is, l know you've changed the glow plugs, but check they are active at start up with a bulb if you can.
Good luck
Bob.

[alanf]

This is similar to what happened on my Daughters pug 207 diesel, it was an air leak, if you pumped up pressure with the little bulb then it would start right away if left overnight or a day or so you had no chance, I fitted a new filter, bulb and some pipe work, its not missed a beat in over 12 months, if you search there is some quite detailed posts on this .