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

[Greg Roles]

Hi Greg,
Try $1500 per injector, and its the wiring loom that starts it all. The insulation hardens, cracks and falls apart, then shorts the injectors to ground, and hey prestor, $7500 worth of headache.
Rob V

Wow now that's both scary, yet interesting. So perhaps if working looms could be better protected from oil and heat, the problem might be minimised....but it would seem both loom and injectors can fail as both are usually replaced at once on warranty claims.

[Hilly]

So, I gather just the loom itself is over $1,000 fitted? I was thinking maybe it would be "cheap" insurance to replace the loom, but of course most units aren't going to experience this fault (I assume), so it may not be $ well spent?

[Static]

Greg,

Have you been able to find out if this is fixed in new cars ? Looks like I'll be ordering mine Monday.

[Transporter]

Wow now that's both scary, yet interesting. So perhaps if working looms could be better protected from oil and heat, the problem might be minimised....but it would seem both loom and injectors can fail as both are usually replaced at once on warranty claims.

I remember seeing the wiring loom failure on 103TDI Golfs with non-piezo injectors. Also loose injectors being reported on Dieselpower.cz for some time. Usual fix is repair the thread in the cylinder head and seal in injector. Without knowing the full history of the failed engine (car) it will be hard to get at the bottom of what cause the failure as many of causes I read are just speculations (IMO).

[PeDiES]

Hi Greg,
Try $1500 per injector, and its the wiring loom that starts it all. The insulation hardens, cracks and falls apart, then shorts the injectors to ground, and hey prestor, $7500 worth of headache.
Rob V

ive gotten a few of these in at work, the problem isn't the loom breaking its the injector shorting out, thats why when it happens the car will not run at all because it shorts the whole circut.

this doesn't damage any of the other injectors or the loom, the main reason (not only reason) vw will change the loom is because the plugs shatter when removing them (sometimes not, no loom required). To replace them you need a tool kit to get them out (which i have) it includes other peices like dial indicator mount so that you can set up the clearances of the rockers.

To sum up, if it happens to your car you can replace just the one injector, ive only seen number 2 fail so far, but ive only done 2 cars.
No doubt the other might fail but i think its worth the $4500 difference to hope for the best.

[Ozsko]

I am surprised that the injector replacement is not a dealer only job. On one brand I know of anyone can replace the injectors but until they are coded to the car the injector will not work and that is a dealer only job.

[Transporter]

I am surprised that the injector replacement is not a dealer only job. On one brand I know of anyone can replace the injectors but until they are coded to the car the injector will not work and that is a dealer only job.

Yeah, Toyota tried many things to fight aftermarket and it didn't work.

[Ozsko]

It works with Mazda, no dealer coding = no go, ask those who have tried to get around it. Panel beaters for instance are finding that after they replace a power steering pump on a Mazda they have to get a dealer to code it also. It surprises me as I said that VW have not gone down this path. Also any one who fiddles with a common rail diesel fuel system had better know what they are doing due to the extremely high fuel rail pressures, it is a job not to be taken lightly. Don't believe it? it's your problem if you get injured.

[benough]

I had one of my injectors fail under warranty but as far as I know the loom stayed.

ive gotten a few of these in at work, the problem isn't the loom breaking its the injector shorting out, thats why when it happens the car will not run at all because it shorts the whole circut.

this doesn't damage any of the other injectors or the loom, the main reason (not only reason) vw will change the loom is because the plugs shatter when removing them (sometimes not, no loom required). To replace them you need a tool kit to get them out (which i have) it includes other peices like dial indicator mount so that you can set up the clearances of the rockers.

To sum up, if it happens to your car you can replace just the one injector, ive only seen number 2 fail so far, but ive only done 2 cars.
No doubt the other might fail but i think its worth the $4500 difference to hope for the best.

[jazd]

So what are the symptoms when an injector fails? Is it catastrophic or does your car just start running on 3 cylinders?

[benough]

Mine just stopped and wouldn't start again. Zero warning.

Maybe you should get onto that used car warranty Jarred?

[PeDiES]

Mine just stopped and wouldn't start again. Zero warning.

Maybe you should get onto that used car warranty Jarred?

most used car warrantys will only cover part cost, hardly worth it

[jazd]

most used car warrantys will only cover part cost, hardly worth it

Yep thats why I'm not bothering.. Whats the deal with VW offering exchanges? I would assume its not free, but I think I read somewhere about them selling the refurbished ones?

[PeDiES]

they will sell you an injector with a core charge which they then return when you return the old injector. The injector cost is there the whole time its just the core charge that comes and goes. My guess is they go back to siemens in mass then the cycle continues

[Greg Roles]

Be great to get a firm price on that, at this stage it seems going OS is FAR cheaper.....