DCi cut out and will not start

[Jamesross]

Hi, im James, owner of a 52 plate Clio 1.5 DCi Extreme and im new to the forums.
Im having a major problem with my car, over the last week I noticed a slight knocking noise, especially at very low speed, I assumed that it was a worn engine mount but today the problems have got a lot worse. I set off from home and after approx 2 minutes the car juddered sharply and then recovered, then a few metres down the road the car cut out completely and will not restart The toxic emission warning light is flashing. When I try and restart the car it turns over but will not fire and it judders shaking the gear lever.

Can anyone suggest what might be wrong and what would need to be replaced to rectify the problem, ive never owned a diesel before this car so i dont really know where to start.

Thanks in advance - James

 

[benji&eka]

possibly an air leak into fuel system or a blocked filter. best start with the cheap bits before the scare mongers start LOL
take it to a diesel fitter/shop
whereabouts in the world are you?

 

[Jamesross]

Hi benji&eka, thanks for your help, I did actually think that the car wasnt as good on fuel as id expected and I did smell diesel once or twice quite strongly but i could never find any leaks so perhaps the air leak could be the cause. Im in Stafford btw.

 

[benji&eka]

i'm a bit far, daventry. i'm trying to think of any good diesel shops in stafford if i remember any i'll let you know

 

[alanhprice]

Hi you will prob gets lots of conflicting advice, could well be a £20 part like a TDC sensor, fail on all sorts of cars.

But consider this my actual experience with a Dci65, superb economy car btw but I had v similar prob to yours, eventually made me sell the car and it is well known to Renault dealers now: failure of EGR valve at typically 30k miles. I phoned 3 dealers to check Shrewsbury/Telford/Coventry and they all said EGR valve straight off.

EGR valves when first came in c 10yrs ago were always sticking on diesels of any make, surprise they got coked up from the exhaust. Renault/Nissan's solution, make the valve shuttle open/shut frequently according to manifold pressure, OAT, revs, etc etc v clever but they have still been failing, usually in the open position.

This builds up excess pressure in the inlet, the MP sensor then shuts down the engine. Possibly after 10mins it will start again but not for long and the prob will just get worse. If failed in shut position car just does not start.

I tried to be clever and keep away from main dealer but the car broke down 5 times and each time independent came up with different answer usually to do with wiring loom or ECU. Swallowed pride, down to dealer, fixed in one morning but cost £550 , valve is built in to whole manifold as replacement.

So up to you but I suggest get the EGR valve checked, any competent mech should be able to see if its working in no time. But nb if not fixed your turbo bearings will blow, don't even think about that cost, I was lucky there. Good luck!

 

[alanhprice]

Sorry just to clarify, EGR is exhaust gas recirculating valve if you didn't know already. All modern diesels have them to cut emissions, esp NOX, dollops of exhaust gas are admitted back in to the engine to be re-burnt under certain running conditions, obv not when you want full power for e.g.

Mentioned if not fixed turbo bearings will blow, well maybe and engine has to run to do this! Point was yr engine might magically run again for a few miles as the valve temp frees itself off and/or a mech may have had a go at cleaning it, but if prob persists it will have been putting undue strain on the turbo bearings while you run the engine

Cheers again

 

[edde]

I tried to be clever and keep away from main dealer but the car broke down 5 times and each time independent came up with different answer usually to do with wiring loom or ECU. Swallowed pride, down to dealer, fixed in one morning but cost £550 , valve is built in to whole manifold as replacement.

The valve isn't cheap but its shoulnd't be that price they must have done other things for that, but usually it can be fixed as such by a good cleaning.

Renault you need to get the car to renault or someoen with a computer clip to see what fault codes are being thrown up as there so complex and computer controlled unfortunatly.

 

[benji&eka]

ooh good point the egr valves are a right fukker!
but i'd start with the basics especially if you keep smelling fuel

 

[alanhprice]

Edde you've made some good points there. But the main one is, yes the fault codes need to be read. Legally any trade mech should have access to them, but it seems only the Renault Clip reader can read them accurately by clearing any irrelevant old ones and only main dealers have one?

I just wanted to make sure the EGR valve is not missed by whoever James gets to look at his car, the indie diesel spec I went to missed it, it's not a pet theory, this fault was exactly what happened with my car, let's hope it is just something cheap to fix though.

As for cleaning the valve, yes it might work and cheaper, but is the valve stuck 'cos they all do it some time anyway, or 'cos this one isn't moving when signalled to by the computer in the first place? It still costs a fair bit to have all the gubbins taken off the top of the engine to clean the valve, no guarantee the clean up will last for long and at what cost to the turbo? If the valve can be replaced cheaper than I paid, fair play and if it's not that that's gone, better still!

Cheers

 

[TomTom]

Swallowed pride, down to dealer, fixed in one morning but cost £550 , valve is built in to whole manifold as replacement.

You got robbed mate, only need to replace the manifold if they break the EGR valve in half and can't get it out!! I'd put money on them breaking it in half trying to get it out.

As for cleaning the valve, yes it might work and cheaper, but is the valve stuck 'cos they all do it some time anyway, or 'cos this one isn't moving when signalled to by the computer in the first place? It still costs a fair bit to have all the gubbins taken off the top of the engine to clean the valve, no guarantee the clean up will last for long and at what cost to the turbo? If the valve can be replaced cheaper than I paid, fair play and if it's not that that's gone, better still!

Good theory, it just doesn't happen - 80% of the time, the valve/housing is that badly clogged up it just can't open or close anymore. The other 20% is usually when the valve just puts its hands up and gives up.

James if you want PM me your address I can send you a home made EGR valve tester if you want.

 

[Jamesross]

Thanks for your help guys, but I ended up towing the car to a local garage and they diagnosed it as a fuel pressure regulator, they quoted me £39inc vat to change it so I had them do the work. The car seems to drive much better than before as well so im happy