VAG COM Transporter T5

[andy8442]

Hi Found this information,but since the vehicle is still under warranty,this should not be your problem. Misfiring at above 3500 rpm.
Mainly no complaint logged. In isolated cases the complaint “ G28 implausible signal” is logged.Rust on the contact surface of the impulse sender G28 to the engine block. This increases the distance of the impulse sender to the sender wheel and the signal can become inaccurate at high engine speeds.One other thing comes to mind and that there has been problems with the wiring harness for the injectors

Thanks will investigate the latter, but 3500rpm? I'd be doing over 100mph at those revs on the motorway! The lumpy running seems to occur more when you ease off the revs and goes when thenpower goes on again.

[kenney]

Have they had any thoughts to the wiring harness?Have YOU thought of trying another dealer?

[Theresias]

Depending on the year, engine code, its ecu part number and its software version there are quite a bunch of potential things which come to mind regarding your problem. Sadly without a real diagnostic protocol there isn't much besides guesswork which one can do for you from distance.

[andy8442]

Have they had any thoughts to the wiring harness?Have YOU thought of trying another dealer?

Hi, someone else has mentioned a wiring harness, Which harness do you mean and what does it connect too?

[Theresias]

The injector harness would be one not too uncommon thing, but thats also something which can easily be excluded without replacing but instead with a test drive and a diagnostic system hooked up. So the question you should ask yourself, do you want to throw expensive parts randomly into the car hoping to fix the problem or do you wanna actually check things before you pay for the parts...

[kenney]

The injector harness would be one not too uncommon thing, but thats also something which can easily be excluded without replacing but instead with a test drive and a diagnostic system hooked up. So the question you should ask yourself, do you want to throw expensive parts randomly into the car hoping to fix the problem or do you wanna actually check things before you pay for the parts...

The vehicle is still under warranty,in all due respect it should be the dealer that should be sorting out this problem.As measuring block values freeze at 1500rpm it is impossible to obtain a reading when the fault occurs.When a fault does not show up on a protocol we have practiced to replace the units.A TB from VW is complaining about the amount of PDs that are being replaced and demand before replacing any units the harness should be replaced first, to see if the fault is rectified

[andy8442]

The injector harness would be one not too uncommon thing, but thats also something which can easily be excluded without replacing but instead with a test drive and a diagnostic system hooked up. So the question you should ask yourself, do you want to throw expensive parts randomly into the car hoping to fix the problem or do you wanna actually check things before you pay for the parts...

The van is still under warranty so if VW want to throw parts at it fine by me, but actually I just want them to fix it. The biggest problem is it's intermittent nature, so getting it to play up when VW have it and plugged up to a machine is seemingly impossible. Which leads me back to my original idea of getting a "device" and plugging it up as I go about my day to day, in the hope that it will play up and I will then have a fault code to help VW track down the problem.

Vw have spent alot of money on the van, claiming against the warranty, to no result. But what the van needs is time on the road with a mechanic and a machine. Now somebody who knows the system better than I can correct me, but I'm assuming the dealorship can't claim on the warranty for time spent roadtesting, only for actual repairs undertaken. Which I'm assuming is why VW had handed me back the van knowing it's still faulty.

I know it's a tricky one and I've even gone over to one of the dealerships and taken the van out for a good run so they wouldn't have to; and now again I'm doing the leg work so....... what do I need to buy to facilitate my idea?

[andy8442]

The vehicle is still under warranty,in all due respect it should be the dealer that should be sorting out this problem.As measuring block values freeze at 1500rpm it is impossible to obtain a reading when the fault occurs.When a fault does not show up on a protocol we have practiced to replace the units.A TB from VW is complaining about the amount of PDs that are being replaced and demand before replacing any units the harness should be replaced first, to see if the fault is rectified

Whoa slow down here you sound like you know what you are talking about. What is the precise name of this harness so I can ask the garage on Monday morning?

[Theresias]

Scratching my head what you mean by measuring blocks "freeze" at a specific RPM, would you mind to elaborate? A generic problem many mechanics have per our experience is understanding what to use and where to go for a proper diagnosis.

In case of injector problem the ECU gives you several values specific to each cylinder/injector. In case of the R5 2.5l TDI you wanna look for MVB 013/014 (Injection Quantity Deviation), MVB 018/019 (Injector Status) and MVB 023/024 (Injector Switch Time Deviation). Especially the Injector Status is what one would be very interested here if you think the wiring is the whats faulty. Now at this point you'll experience one of the major flaws wirth the original manufacturer diagnostic tools (VAS 505x), they are not able to log data in a continuous stream and occasionally you will miss important events when for example the measuring block shows an electrical fault or a injection deviation. This is where VCDS (formerly known as VAG-COM) is superior, even though it gives you the same values on the screen and you can still miss the important point it does allow to save a log file and thats what you should look at in a case like that once you ended your test drive.

The harness part number is specific for the actual engine code and model details like build date, nobody will be able to give a specific part number with the few information you posted so far.

[kenney]

When i say freeze,it means the readings in MBV 13/14 stop at 1500rpm.The problem is often in the range of 2500-3000rpm,which makes it impossible to get a reading.I have never used VAG-COM,and from your comments, this must be superior to VAS 505x Regarding the generic problem of many mechanics,i feel the 46years i have been working with VW+Audi makes me confident to know what to use,and how to use it.