All common rail diesels are inherently flawed?

[hitman67]

Before I start, I used to have a common rail (02 Audi A4 Cab 2.5TDi) But now have something VERY pre-common rail (89 Land Rover TD).

The A4 Diesel was Superb. Being a V6 TDi there was very little diesel clatter and the roar of a V Engine soon took over in high revs, especially with the lid down. I bought mine with 55k on the clock and sold it with 106k and never missed a beat. Really solid engine.

The Landie on the other hand, well that is a tractor. I get 30mpg if I drive carefully and the old diesel noise whenever. But I didn't expect it to be efficent, or quiet, or easy to drive. For what it is, it is bloody great. and for a 2.5 tonne truck with the aerodynamics of Rik Waller 30mpg is really good going.

[Neo_VR]

Its all just technological progress..

remember the early turbocharged cars, the turbos would need rebuilding every 60k miles because of bearing wear, modern turbos dont have bearings and can go on and on and on (as long as they have oilchanges as per spec)

early fuel injection... again, the injectors would degrade and need ultrasonic cleaning with age.

even carbs/throttle bodies were not perfect... the GM VarijetII on vauxhall engines were well reknown for wearing out and causing running problems!

also as time goes by and manufacturing processes improve, the current CR-injectors will get cheaper to make, and therefore cheaper to replace in case of failure.

[el hunga]

Hello Chaps,
I have a problem that Im trying to sort out, I have a volvo D5 diesel and my mate took the car out for a drive and ran out of diesel. He kept cranking the car and now I have a problem with the fuel rail, I took it to get inspected and they confirmed that the rail was causing the car to run out and stall, they said that the valves inside were malfunctioning and the pressure was going up and down like a yoyo.
The thing is that it has not happened before and I find it hard to spend so much money replacing the rail as it was only out of diesel.
We replaced the pump to be sure and its still the same, we inspected the crank angle sensor and same thing.
I guess Im asking whether anyone has had the same problem before and is it common for this to happen???
I just want to be sure before we buy the part.

Thanks.

[kalniel]

I've not had the problem myself, but yes it's fairly clear in most manuals that running out of diesel in a high pressure engine is very bad news.

[UseItNow]

Hello Chaps,
I have a problem that Im trying to sort out, I have a volvo D5 diesel and my mate took the car out for a drive and ran out of diesel. He kept cranking the car and now I have a problem with the fuel rail, I took it to get inspected and they confirmed that the rail was causing the car to run out and stall, they said that the valves inside were malfunctioning and the pressure was going up and down like a yoyo.
The thing is that it has not happened before and I find it hard to spend so much money replacing the rail as it was only out of diesel.
We replaced the pump to be sure and its still the same, we inspected the crank angle sensor and same thing.
I guess Im asking whether anyone has had the same problem before and is it common for this to happen???
I just want to be sure before we buy the part.

Thanks.

Which model year D5, the current one, 2004 onwards?
What have they quoted you for it and is that at a dealer or specialist?

How is the drive of the D5 in general, if it is the 2004 onwards model?

[el hunga]

Hello again,
The model that I have is the 2001 model S80.
The technical information was given by a specialist and we connected the lap top to the car and found that the fuel pressure was ok and so was everything else but the fuel rail pressure was going fom 50 PSI to 500 PSI up and down just at idle.
I wanted to know if anyone has had the same problem before???

The car drives great, plenty of power from the turbo, quite surprising actually.
Not much lag on take off but dies a bit at mid range.
A bit more boost would be great, might adjust the actuator later on once we overcome this problem.

[dave87]

How is the drive of the D5 in general, if it is the 2004 onwards model?

Got one sitting on the drive at home - its Mum's car. Ours is on an 07 plate, but same model as the 2004 onwards (just before the changeover), with the 185bhp engine.

Brilliant engine, nice and torquey, drive from very little revs. Fuel economy is 10-15mpg better than the 2.4 (170) Petrol v70 we had before. Smooth, very quiet except when cold, when it does sound a little like a diesel. I personally think it sounds better than the petrol engined one it replaced.

Ours is mated with the Geartronic Box, which isn't bad at all, but is not as good as the Tiptronic boxes found in BMWs. Overall though, a fantastic car & engine.

[UseItNow]

Got one sitting on the drive at home - its Mum's car. Ours is on an 07 plate, but same model as the 2004 onwards (just before the changeover), with the 185bhp engine.

Brilliant engine, nice and torquey, drive from very little revs. Fuel economy is 10-15mpg better than the 2.4 (170) Petrol v70 we had before. Smooth, very quiet except when cold, when it does sound a little like a diesel. I personally think it sounds better than the petrol engined one it replaced.

Ours is mated with the Geartronic Box, which isn't bad at all, but is not as good as the Tiptronic boxes found in BMWs. Overall though, a fantastic car & engine.

Cheers mate, have driven a S40 2 litre diesel, was rather good, but felt it needed just that more pull but then again I am use to driving more powerful cars.

How do you think the manual will compare to the Geartronic?

Thanks.

Edit: As yours is a 07 plate, how are your dealers, presuming you are taking it to the dealers for servicing? How are your servicing costs? I ask as the couple of times I've been at a dealers, waiting to be seen, near the service counter, the servicing costs seemed ridiculous (typical, was around £400+) for some of the owners.

[dave87]

No idea on the costs, as I don't deal with that side of things. Manual vs Geartronic? The manual will give you more control, but if you are lazy, and driving a bigger car (ie V70) then its a good option. I personally would buy a manual, but Mum and Dad seem to like the geartronic.

From what I've been told, the dealer we use is absolutely useless. Possibly even insert a word beginning with F in there if you like.

Car arrived, no problem, except the glovebox had a mark on the trim panel. Being a brand new car, we wanted it to be right (no way it should have left the factory like that tbh). Fine, but would take a while.

Got the car back after they replaced it, glovebox didn't open/close properly. Sloppy, and bloody annoying. Finally fixed some 6 or so months afterwards.

Parking sensors, not worth the extra box. Absolutely useless, random bleeps, inconsistent reaction to obstacles, sometime not even registering. Working fine according to Volvo. Ongoing "discussion" to which Mum has given up. If it were me, I wouldn't be so relaxed about the whole thing.

Probably just our dealership, but unfortunately they are the ones in the surrounding area (chain in Essex).

[UseItNow]

Thank you for your reply again Dave. Appreciated.

[digit]

Hmm interesting thread, kinda semi put me off the idea of getting a diesel next.. Its just all the torque is very tempting and the MPG.

From what I've been told, the dealer we use is absolutely useless. Possibly even insert a word beginning with F in there if you like.

Would it not be worth your parents going to a Volvo specialist as opposed to a main dealer? My friends dad who owns an almost new Volvo S60 does exactly that and apparently its cheaper and better then the dealer?

[dave87]

Yup, they've thought about that, but I think their conclusion was it was marginally easier to go to the dealership rather than have an problems should we need to make a claim under the warranty.

[GavinS]

Quite prophetic the original post given that it was almost 2.5 years ago.

Reading HonestJohn, there are all sorts of fuel pump and injector failures with the TDCi engines in the Focus/Mondeo and even more problems with the common rail engines in the Mazda 5/6 diesels.

[caepabi]

TECHNICAL FEATURES
The Common Rail Diesel Injection System Explained
By source: Robert Bosch GmbH
Jun 7, 2004, 10:15
In recent years, more and more drivers have been drawn to diesel-powered vehicles. Bosch has played a major role in this European diesel boom. The modern high-pressure injection systems VP44 distributor-pump, Unit Injector and Common Rail have transformed the ponderous, smoke-belching slowcoaches of yesterday into the sporty, fuel-efficient and clean automobiles of today.

The Common Rail system in particular gives engine developers the freedom they need to reduce exhaust emissions even further, and especially to lower engine noise. The particular design of Common Rail, with its flexible division of injection into several pre-, main and post-injections, allows the engine and the injection system to be matched to each other in the best possible way. In the Common Rail accumulator injection system, the generation of the injection pressure is separate from the injection itself. A high-pressure pump generates in an accumulator – the rail – a pressure of up to 1,600 bar (determined by the injection pressure setting in the engine control unit), independently of the engine speed and the quantity of fuel injected. The fuel is fed through rigid pipes to the injectors, which inject the correct amount of fuel in a fine spray into the combustion chambers. The Electronic Diesel Control (EDC) controls extremely precisely all the injection parameters – such as the pressure in the Rail and the timing and duration of injection – as well as performing other engine functions.




In the 1st and 2nd generation of Bosch's Common Rail, the injection process is controlled by a magnetic solenoid on the injectors. The hydraulic force used to open and close the injectors is trans-mitted to the jet needle by a piston rod. In the 3rd generation of Common Rail for passenger cars, the injector actuators consist of several hundred thin piezo crystal wafers. Piezo crystals have the special characteristic of expanding rapidly when an electric field is applied to them. In a piezo inline injector, the actuator is built into the injector body very close to the jet needle. The movement of the piezo packet is transmitted friction-free, using no mechanical parts, to the rapidly switching jet needles. The advantages over the earlier magnetic and current conventional piezo injectors are a more precise metering of the amount of fuel injected and an improved atomization of the fuel in the cylinders. The rapid speed at which the injectors can switch makes it possible to reduce the intervals between injections and split the quantity of fuel delivered into a large number of separate injections for each combustion stroke. Diesel engines become even quieter, more fuel efficient, cleaner and more powerful.

For its 4th generation of Common Rail for passenger cars Bosch is currently exploring designs using even higher injection pressures of more than 2,000 bar, as well as injectors with variable injection geometry.




Bosch Common Rail injection system –
Milestones of development

1997:
First Common Rail system in the world for passenger cars.
Injection pressure: 1,350 bar.
First production use: Alfa Romeo and Mercedes-Benz.

1999:
Common Rail system for trucks.
Injection pressure: 1,400 bar.
First production use: Renault (RVI).

2001:
2nd generation Common Rail for passenger cars makes diesel engines even more economical, cleaner, quieter and more powerful. Injection pressure: 1,600 bar.
First production use: Volvo and BMW.

2002:
2nd generation Common Rail for trucks gives lower emissions, improved fuel consumption and more power.
Injection pressure: 1,600 bar.
First production use: MAN.

2003:
3rd generation Common Rail with rapid-switch piezo inline injectors for cars.
Advantages: up to 20 % lower emissions or up to 5 % more power or up to 3 % lower fuel consumption or up to 3 dB(A) less engine noise.
Injection pressure: 1,600 bar.
First production use: Audi.

The 3rd generation Comon Rail from Bosch is characterized by rapid-switch, compact piezo-inline-injectors. The innovative injection system provides for low exhaust emissions in the new V6 diesel engine of the Audi A8.

[el hunga]

Hi Guys Long time no here.
I have been away and only recently got back on track.
Regrading my Volvo you wouldnt believe it has not been rectified.
I was told that the fuel rail was the problem. I managed to get it inspected and it was OK.
Then I was told that the injectors were faulty and the needed replacing. I managed to get them inspected and they also were OK.
After 2 months of the car sitting around it started and ran great. I did 150 KLMS then put some more Diesel in the tank. When I was leaving the station I accelerated very quickly and you wouldn't believe the fault came back again.
I guess I'm asking if anyone has had this happen to them also???
Remember it all started when he ran out of diesel.
If the fuel pressure regulator is faulty would that cause the car to run out of diesel while driving making me having to start the car again???
If I check for diesel in the line its empty.
Fuel pump replaced, rail inspected OK, injectors inspected OK, fuel filter replaced, air filter new.
Please guys I really need help...

[wesjac]

Hey El Hunga,
Could be air entering the system. Otherwise, try the rail sensor, or have you swapped the pressure regulator yet?