Injector failure and subseqent damage

[eddieh1]

Hello, my first post on here...

I have an A4 2.0 170 tdi 56 plate. about 5 weeks ago the engine stalled and roadside assistance came out diagnosed an injector wiring loom failure.

Several days later, they checked on my warranty situation and fitted a new wiring loom and injector.

The service center called to say my car was ready for collection, but added did i notice any engine noise prior to the stalling. I said no, and was promptly told it was unconnected and nothing to wory about.

Went down later in the day, got the keys and found that the unconnected noise was what can only be described as running on three cylinders.

The car stayed in their car park.

A week later and several calls, I was told it was ready.

It survived the 1 mile drive back to where I work, but upon starting the car again, it made the car shake from side to side and sounded like it was back to 3 cylinders.

The 1 mile drive back involved a mettallic snapping noise from the engine, and no power.

The car has stayed with them since.

Audi customer services were then involved, and suprise suprise they started to talk/keep me informed.

The service manager called to say it was a balance shaft last week.

This week it was another injector, a balance shaft and a snapped cam shaft.

My question's are:

can 1 injector failure cause all this?

can 1 incompetent tech cause this?

What is the possible long term damage? i.e bits of metal floating around for a mile.

What compensation can I expect? Audi have already asked what kind of goodwill gesture i wanted.

I Said i wanted a new engine!!!


Eddie

[a8 tech]

Firstly the initial fault would have been the failure of the piezo injector element short to earth and audi asisit are not audi technicians they are rac.
The original Audi assistance funded by Audi used a6 allroads and in general were all ex audi techs and they were a good set of lads.

As i have mentioned numerous times the failure is not the wiring loom but internal short of the piezo element often caused by one injector failure but followed by the other 3 soon after.

Warranty does not permit more than one injector to be replaced unless there is a stored fault code for the others.

As for your noise then if the counter balance oil pump gear teeth have worn or the oil pump shaft has worn causing the noise and no excess swarf has entered the oil circuit then it is just a case of repairing the oil pump and does not warrant the engine replacement.

The dealer does not have to replace the engine because you think it should as they alone will have to stand the £8000 plus cost if rejected.

There is no connection between injector failure and the oil pump as the injector just stops so no fuel is injected, the oil pump failure is down to wear or poor lubrication/manufacturing materials used for the gear drive/shaft

The third year of the warrant or good will is split between manufacturer and the dealer so the dealer stands the labour and the manufacturer stands the part providing the suggested
repair is within warranty guidelines.

It appears you have two faults and should treat it as such and not attack the dealer.

[patrickhorton]

Do you mean three faults not two? The snapped camshaft must surely be unrelated to the balance shaft but maybe not to the repair of the injector...

[Crasher]

The snapped cam is usually due to a failure of lubrication on a journal along the cam from the drive end, not the fault of the cam itself. Grab hold of a brittle stick (a nodular cast iron cam is brittle) and twist the other end and it will snap, effect not cause.

[eddieh1]

The car has now been back in a few more times.

Still has a problem though.

At approx 55 degrees to 75 (water temperature), the engine seems to skip a beat, the car rocks and a puff of smoke/steam comes out of the exhaust. This happens every 10 seconds and then when i do clear the traffic theres a large cloud following.

First they fitted a restrictor to the egr valve.

This helped but didn't resolve.

They then carried out a diagnostic with me driving.

One of the injectors was delivering approx +2 mg/???

The other 3 were compensating at -0.5mg/??

They have said one day the're not sure what to do next.

Now they say its normal behaviour.

Car's booked in at another dealer now.

Hope someone can help/put my mind at rest becaus it never did this prior to my injector failure.

Thanks

Eddie

[Crasher]

Don’t take any notice of the temperature reading on the gauge, I see them read 90 when they are actually at 75 and still reading 90 at 117, I do not know why they have made the gauge read like this.

Injector compensations can swing all over the place.

[eddieh1]

Temperature guage reading may or may not be accurate, however my fault always occurs at the same reading.

I can appreciate what they say about the egr valve kicking in and causing a blip, but could it really do it so regular until it warms up?

Has anyone else experienced this?

[patrickhorton]

Temperature guage reading may or may not be accurate, however my fault always occurs at the same reading.

I can appreciate what they say about the egr valve kicking in and causing a blip, but could it really do it so regular until it warms up?

Has anyone else experienced this?

Yep. Exactly the same. I have same car same reg and I dread being stuck in traffic after a cold start. Spent a long time using VAGCOM to understand the problem. There is a new software release from Audi which I'm hanging my hopes on. A8tech quoted the following: "sw 9973 is the latest software update and rectifies egr and fuelling problems." Going in for a service in the next few weeks and I'm going to ask for it.

My car has no exhaust filter (DPF) and so you can see any muck the engine kicks out. During the warm-up on idle, the exhaust stinks and smokes - the engine is well overfuelled/air-starved. When the DPF was fitted, i just used to get loads of steam like you are getting.

I agree with your comments on the temp gauge. Accurate or not, mine is consistent almost to the degree. You get used to noticing how the gauge rises each day and it always rises at exactly the same rate - I trust it.

I've read about this problem with the A6 and the known fault refered to the temperature range 40 to 70deg. I think there was a software solution for that too.

Please keep us updated.

Patrick

PS there is a guy posted in this section of the forum on 21-07-2010, 10:46 PM (Phantom) with the same problem but he's gone quiet.

[a8 tech]

the sw update improves dpf warm up and egr

values required to diagnose idle and fuel

001 Injection quantity
Coolant temperature min. 75°C:
1) Engine speed
At idle: 870 ... 890 rpm
At full throttle: 2800 ... 3200 rpm
2) Injection quantity
At idle: 3.0 ... 10.0 mg/stroke
At full throttle: 45 ... 75 mg/stroke
3) Specified duration of delivery
At idle: 3 ... 9 °CA
At full throttle: 20 ... 30 °CA
4) Coolant temperature
Less than 75°C: => Warm up engine

013 Smooth running control
Measured values at idle after approx. 15 s, coolant temperature min. 75°C:
1) Injection quantity variation cylinder 1 [mg/stroke]
2) Injection quantity variation cylinder 2 [mg/stroke]
3) Injection quantity variation cylinder 3 [mg/stroke]
4) Injection quantity variation cylinder 4 [mg/stroke]

Note: To specify the permissible limits, the
current injection quantity must first be determined from measured value block 001 zone 2.
* The table below then shows
the permissible values for the idling speed smooth running control injection quantity.
* If the injection quantities listed
in MVB 001/2 at idle are not reached,
consumers should be switched on as necessary.

Injection volume Limits of injection
from MVB 001/2 quantity cyl X
5 mg/stroke -1.90 ... 1.90 mg/stroke
5,5 mg/stroke -2.09 ... 2.09 mg/stroke
6 mg/stroke -2.28 ... 2.28 mg/stroke
6,5 mg/stroke -2.47 ... 2.47 mg/stroke
7 mg/stroke -2.66 ... 2.66 mg/stroke
7,5 mg/stroke -2.85 ... 2.85 mg/stroke
8 mg/stroke -3.04 ... 3.04 mg/stroke
8,5 mg/stroke -3.23 ... 3.23 mg/stroke
9 mg/stroke -3.42 ... 3.42 mg/stroke
9,5 mg/stroke -3.61 ... 3.61 mg/stroke
10 mg/stroke -3.80 ... 3.80 mg/stroke

[eddieh1]

Got the car back last week, all good

They had to change...

Cylinder head.. due to pitting around injector seats

All 4 injectors

Inlet manifold.. cracked

Flywheel

Clutch.. goodwill gesture by audi

16 hours of labour doing all this, thank god it was all warranty.

Big thanks to Simon at Doncaster Audi.