c5 hdi 2.0ltr 2003 LX

boristhespie · Post by **boristhespie** » 10 Oct 2010, 13:13

c5 hdi 2.0ltr 2003 LX

After months of just sitting my other half decided to put c5 into garage. those of you with long memeories will recall there was a power problem in that when going uip shallow but long hills the power would simply not come on as if it was being held behind.

The engine management light is on.

The garages said initially that it was difficult to diagnose until something more major went ahead.

Anyway put it in yesterday. Had to jump battery so some faults may be reulst of that. My wife phoned so these are just a list of fault codes.

preheating
relay circuit
glow plugs
airflow meter

The last one seems to be of interest.

I thought it may be my injectors not working correctly.

However the garage (A bosch) said it may be the egr valve sticking.

70 quid for new one plus time

JUst thought I;d run it past you guys for any thoughts before go ahead.

cachaciero · Post by **cachaciero** » 10 Oct 2010, 19:08

Seems very possible to me.

Wheeler had an explanation for this in an other post which made sense to me at least. i.e. The mass flow sensor doesn't do a lot on diesels but is used as a monitor of EGR performance.

Mind I would strongly suggest checking that the vacuum side is in order before changing the valve, a thump with the FBH tool might be in order too

cachaciero

Post by **myglaren** » 10 Oct 2010, 19:12

Of those listed I'd expect the MAF and EGR to be the most likely suspects.
EGR could be checked rather than just exchanged. It either works or doesn't.

Mine has developed a similar problem. No turbo boost until ±3,200 revs, after which it runs fine.

I had the MOT station cast an eye over it and they did a diagnostic but not with a Lexia. There were some indications that it could be either the MAF or EGR but they weren't at all sure.

After I collected it it went like stink, despite them saying that they had been unable to address the problem.

Called in the next day to thank them and the guy who had worked on the car said he had taken of the turbo pipes and checked them, along with the vacuum hoses. All were cleaned and replaced but there was next to nothing to clean out and he was unable to see any problems.

The improvement lasted a week.

I'm convinced the problem is an air leak somewhere, most probably in one of the vacuum lines.

Clogzz · Post by **Clogzz** » 11 Oct 2010, 12:33

When coasting downhill the EGR electrovalve opens to see if the MAF meter will find out.
If it does, it’s assumed that the EGR works normally.
Otherwise the ECU’s got the choice of blaming either, depending on the degree of reaction.

The valve can be stuck slightly open without the ECU noticing.
Cleaning it is an easy job, but with the risk of the mounting bolts or the thin metal gasket escaping.
Reassembly needs a mirror to centre the gasket and bolt holes.

Post by **Paul-R** » 11 Oct 2010, 12:37

Clogzz wrote:Cleaning it is an easy job, but with the risk of the mounting bolts or the thin metal gasket escaping.
Reassembly needs a mirror to centre the gasket and bolt holes.

You've actually cleaned the EGR onn HDi in-situ? I looked at mine and came away shaking my head.

Clogzz · Post by **Clogzz** » 11 Oct 2010, 12:49

No, that was on the petrol car.
It’s accessible, but the bonnet doesn’t lift high enough to see.
One of the bolts escaped, and the undertray caught it.
I had to use a mirror at reassembly and put a pencil down one bolt hole while I tried to start the other one.

Are we both talking about the electrovalve ?
Item 1 in the diagram.
The non-return valve, item 6, I get wobbly knees

at the sight of it.

Post by **Paul-R** » 11 Oct 2010, 14:33

That's a twin-cam head, isn't it?

Anyway, yep No6.

Clogzz · Post by **Clogzz** » 11 Oct 2010, 15:28

Yes, twin cam 2 litres.

Item 6 is a non-return valve to prevent the exhaust gas from blowing backwards into the engine room.
Item 1 has the recirculated exhaust going through it, and that causes the plunger to stick.
It’s not quite like an electrovalve that’s open or shut, it regulates the amount of recirculation by varying the opening.

boristhespie · Post by **boristhespie** » 11 Oct 2010, 16:34

OKay left my wife to deal with this.

Anyway, apparently the garage says airflow and something to do with "glowplugs, relay circuit or something" is showing up as faults.

The scary bit is the sentence "he says there is a common fault that can cause these with the, I can;t remeber what he called it, but it costs £600 to replace"

Eh can we please help me here?

Post by **myglaren** » 11 Oct 2010, 17:36

"£600 to replace" sounds rather like the fuel pump.

boristhespie · Post by **boristhespie** » 11 Oct 2010, 18:38

Well she said he told her that it was something which can cause airflow and glow plug faults.

Wasn't fuel pump.

Good leaving it to her... it's so clear.

Should I have said that?

Citroenmad · Post by **Citroenmad** » 11 Oct 2010, 20:25

I think EGR valves are quite expensive, but not that much!

Whatever it is, somehting with is £600 new is much cheaper used! I can't think of a common fault with C5s which would result in this.

Our C5 estate was showing up a fault code with the EGR, it was not performing under 2000rpm and would try to stall. We tried using some air intake spray, to clean the EGR and after a few goes the car performed noticably better. Since the code was cleared its been fine since and now performs as normal.

Pootling about can block up EGRs and they often require a good clean.

cachaciero · Post by **cachaciero** » 11 Oct 2010, 22:55

Hmm...! One could say that a fault in the ECU could cause all those faults and would be about £600.00 to replace, and no you can't use one from a scrapper because the VIN code plus other security stuff is hard coded .

cachaciero

Citroenmad · Post by **Citroenmad** » 12 Oct 2010, 07:45

Very true

boristhespie · Post by **boristhespie** » 17 Oct 2010, 11:43

OKay they blanked off the egr saying that it would prevent the codes. Both codes came back so they suspect the Engine Management Unit (?) that's £600 and not possible to change really?

Any thoughts