103kW/125kw TDI PD Piezo Siemens injector failure thread

[Ozram]

Hmmm, interesting thread.
I'm not suggesting any of you may be tempted to tinker with the high pressure fuel injection equipment, but thought I'd give a little warning about the dangers involved if you do.

The fuel pressure in common rail systems is immense. The flowjet machine that American Chopper uses to cut steel with water pressure runs at about 6-800 bar. Common rail injectors can operate in excess of 2000 bar!
Never loosen or re-tighten a high pressure injector pipe as a means of diagnosis, they are usually single use only pipes - I may be the next one to diagnose your vehicle and don't want a face full of high pressure fuel.
Voltage at the injectors is typically over 200.

And one you may not know..........
A piezo injector is different to the older style CR injector in that it needs two pulses of electrical current to operate not one. A pulse to turn it on and another to switch it off. If you were tempted to electrically disconnect a piezo injector to stop it operating, you may be unlucky enough to disconnect it in the *on* position.

Result - An injector pouring enough fuel into your cylinder to make it hydraulic lock.

Be careful with this stuff guys.

[kaanage]

Where did the CR injectors come into this thread?

So are you saying that the engine gets killed by the ECU, when it detects a Piezo solenoid injector failure, to prevent the possisbility of hydraulic lock. Then the cars just shutting down is more understandable but it seems like a very poor overall design if injector (or loom) failure REQUIRES the engine to shut down in order to prevent catastrophic damage.

And by "older CR injector", do you actually mean "older PD injector" which is closed purely by the return spring ?

[Ozram]

Just a timely reminder about the dangers of high pressure diesel systems. I still get many phone calls from people who think that cracking an injector pipe nut to look for fuel is a good method of diagnosing their broken down vehicle.

No, I'm saying that if you decided to unplug a piezo injector electrically, as a method of checking for a cylinder misfire you could detonate your engine.

No, not pump deuse. By older CR injector I mean solenoid controlled not piezo crystal controlled. The fuel pressure inside the injector is constant, it actually holds the needle in the closed position on the seat. The solenoid or piezo crystal stimulates a port opening that lifts the needle and opens the injector.

[kaanage]

So if the new CR injectors are also actuated using piezo electric crystal stacks, does that mean all the new high pressure CR engines are also prone to this failure mode?

[RobV]

The PD injector issue is obviously well known, would be interesting if any VW mechanic could give numbers to this problem. A friend of mine owned a business and had 2 passats in a row and both failed.(refused to get another one!) he warned me about the reliability issues before I bought my GT sport in 2008, I ignored his advice because mine was a newer model! So this has been around for a long time in Passats. But if the issues is a s big as it seems! (also Check UK web sites) why did VW persist with the same Injector/wiring kit????.
Are the replacements an improvement or the same parts????
Hope my car will be ready today, but my confidence has been shaken in VW reliability.

[Transporter]

So if the new CR injectors are also actuated using piezo electric crystal stacks, does that mean all the new high pressure CR engines are also prone to this failure mode?

It is unlikely, since the CR injectors and their wiring aren't surrounded by hot and dirty engine oil, but for confirmation of that, you have to wait little bit longer.

[Russ59]

Mines been missing a bit every now and then, it has also on occasions been very jerky when I actually switch the engine off (feels a little bit like it's running on) it did this the other day and has been OK since. All this talk of these injectors failing is making me wonder if this is what happened to mine when I first took delivery in 2008, I made mention of what happened in an earlier post and put it down to a cold engine DPF Regen, just wondering now if it could have been an injector issue. Mine is out of warranty in September this year, I think the extended new car warranty will be a definite consideration as it would more than pay for itself in the event of injector failure. I totally agree with others that there should be a recall especially when engine failure in traffic could be life threatening. I'd be interested to hear comments from others as to what symptoms they had experienced prior to their injectors failing.

[Greg Roles]

My vote Russ is oil sludge gumming up your flap mechanism whose job it is to stop airflow for a smoother engine stop. That same sludge causes hesitation problems when the nearby EGR valve can't operate correctly, especially at speed when you plant it.

Have you ever cleaned it out mate?

[Russ59]

My vote Russ is oil sludge gumming up your flap mechanism whose job it is to stop airflow for a smoother engine stop. That same sludge causes hesitation problems when the nearby EGR valve can't operate correctly, especially at speed when you plant it.

Have you ever cleaned it out mate?

Hey Greg, it hasn't had any issue with hesitation when I plant it, it still pins you to the seat on acceleration and is very responsive at speed when you put your foot down. Other than checking oil and fluids I haven't laid a spanner on the engine, I took one look under the bonnet of this beasty and decided I'd leave it alone, I still like to get adventurous under the bed sheets but not under the bonnet of a car (not the late model ones at least) Is this something the dealer would know about and fix under warranty or will I have to get my hands dirty? I'm guessing there is already a thread on it here somewhere ? The part that pi$$es me off is that I bought a diesel for reliability and although it hasn't let me down yet (fingers crossed) it would appear that there is a strong possibility it's going to at some stage, whether it be injectors, DPF or some other glitch. I can't imagine not having this car as I love it, but it's annoying to think that VW must be aware of these issues and does nothing about it until people start complaining

[Transporter]

If you look under the car at the 2 hoses attached to the intercooler, they are most likely wet from the oil and you may even see the oil drop at the connection. It's like that one every Golf TDI I see and our MK5 in no exemption. Throttle body needs to be cleaned otherwise it will cost much more when the flap fails.

[benough]

Sad news everyone.

My GT Sport failed last Friday. It had been stuttering here and there in the weeks leading up to it.

The dealer just told me that they are replacing all four injectors.

The odometer is 100,256 so my extended warranty is kicking in. SO happy I bought it.

Does anyone know if they are putting the same old injectors that are prone to fail in there if there is a revised version that's better?

Will post again when I know more.

[kaanage]

I spoke to someone today who has a Passat 125kW TDi and he had 2 injectors fail and then replaced a few weeks ago and then the other 2 injectors fail and replaced this week. I told him to make sure the loom was replaced along with the injectors and he was told that they were.

He also asked why all 4 injectors didn't get replaced with the initial failures and he was told that his dealer tried but the company which underwrites the extended VW warranty only authorised the replacement of the failed injectors.

[Greg Roles]

Am heavily researching this and will post good things I come across. At least this site suggests that the replaced injectors and loom are different, upgraded models. A fair bit cheaper in the UK too.

UKpassats.co.uk • View topic - 2.0 TDI Injector Upgrade

[Don61]

2006 Passat 103kw TDI DSG wagon failed at 4 years and 150,500 km.

My 2006 Passat 103kw TDI DSG wagon failed last week, March 2011. It was purchased new March 2007 in Morwell Australia. Its just 4 years old, in immaculate condition with 150,500km on the clock. It has been fully serviced by VW, on time every time.

Problems started months ago with a stutter or misfire at very low speed. This was minor and I was about to report it with the 150,000km service.

Engine just stopped when it had been cruising at 100 kph for about 15 minutes. An engine fault alarm was displayed and glow plug light flashed continuously. Turned ignition off and restarted. Engine started with no alarms and drove for further 45 minutes. Engine was turned off and would not start again. Contacted VW and car was towed away. It was already booked in for its service at local Morwell VW dealer.

Morwell service guy contacted VW and negotiated 70% warranty 30% owner cost split for repair covering labour and materials but exclude towing cost. This seems fair given age and km’s travelled plus outside of warranty. However my expectation is that injectors should last for life of the car say 600,000 km. I note that injector are not listed as a service item in the first 300,000 km

Costs of repair including GST totaled $4,579. This was made up of Labour of $352 and Materials of $4,227. Materials were 4 injectors, 1 harness and 8 head bolts. Of this my 30% share cost $1,374 plus towing cost.

In summary things sometimes go wrong in the real world. VW did come to the party with repair cost. It also cost me and having paid once I don’t want to be hit again by accelerated depreciation when I come to sell the car. VW therefore need to solve this before it damages its reputation.

Thanks to all for the information on this site. Don61.

[Greg Roles]

I've found the guys in the UK are thinking it is the loom rather than the injector itself that shorts...but seems no-one is still sure what is going on. They are having the same sort of failures we are, cars dropping left and right.

Have a few leads on refurbishers, but still awaiting an actual email response!! I'm hanging onto this like a pit bull - mainly because as of April I have no more warranty!!