My GTD died! Potential warranty issues...

[JoeGTI]

Hi guys,
Looking for some advice. My 2 year old MK6 GTD (25,000 miles on the clock) died on me yesterday without warning. I was pulling out of a multi-story carpark when suddenly warning beeps started going off and I got a "Check Engine" warning message (among loads of other errors - traction control fail, ESP fail, xenon bending lights fail!) in the MFD. I stopped the engine and it restarted again, but was a bit gruff, and it cut out again. Attempts to restart didn't work and it was very rough sounding on turning over.

As luck would have it, the car is still in warranty for just a few more weeks (we get 2 year warranty here).

Eventually, the AA (VW Assist) came to my rescue and they got the car started again, just so I could get it out of the carpark. It felt noticeably rough, i could feel some vibration through the steering wheel. The AA man's best guess was a crankshaft sensor failure and that the car was in "limp" mode.

Anyway, this morning, the VW dealers called me to say they have looked at the car and they are struggling to connect and/or read faults from the ECU with their diagnostics. It is behaving strangely and throwing up all sorts of lights/warnings in the dash. The cooling fan is also coming on more often than it would normally. So as a first step, they have ordered a new ECU!! This sounds very drastic to me...!

They asked me was the car tuned/remapped and I said no. He seemed to take my word for it and we left it at that.

This is where it gets complicated 
Over xmas, I did bring the car to a very reputable tuner who attempted to remap it for me. It was an ECU-out job, so he had the ECU opened up and was fiddling with it obviously. Anyway, as it turned out, the map refused to work, he couldn't get the software patch to upload onto my ECU, so he sealed up the unit again using the original screws, etc, and put it back into the car. This was 6 months ago and the car was perfectly fine until yesterday.

I'm a bit worried that VW will twig that the ECU was tampered with. The dealers have ordered a new one,  but will they bother to check the old one when they take it out, to see if it was messed with? Are there obvious signs that it would have been opened? I remember there just being a few screws, I don't remember any anti-tamper seals or anything, but then again I wasn't paying that much attention on the day.

I suppose I'm just looking for someone to tell me that VW aren't going to take my pants down!

[Rhyso]

If the tuner has done the job correctly then it should look like they were no where near it.  Hopefully they were very careful and replaced it without a scratch.......

At some point I would assume diagnostics would be carried out on the ECU as they are not a common failure 

I'd think you'd be 'OK' 

If it was something the tuner had done then I would have thought it would have pretty much failed after it was replaced in the car or even refused to start / cut out whilst it was there

[JoeGTI]

Thanks Rhyso, that's somewhat reassuring.

I'm surprised that they are resorting to just replacing the ECU as a first step. His reasoning was that they couldn't connect to the car with the diagnostics, it wasn't giving them any proper readings or fault codes. All he could tell me was that the car was acting "strangely"!

Yeah, its almost 6 months since the tuner had the ECU out, so as you say, if it were to fail because of that, it would have failed back then  surely. It was running completely normally with no issue up to yesterday.

I suppose it's fingers crossed time and hope that the VW dealers just swap out the ECU and don't go forensically examining the old one. I'm 99% sure that the tuner was careful with it. The only thing I remember him doing was re-appling some silicone (?) sealant to the casing before screwing it back together.

[stevieC]

Joe the same thing happend to me when my gti was just under 2 years old,had it mapped by revo then 2 days later went into limp mode they advised me to take it to my dealer.The first thing the dealer asked me was have you had your car remaped to which I said no,to cut a long story short they had the car for over a week changing different parts then they changed the ecu,all was fixed under warranty & the tech said the only way for them to check the old ecu was to send it back to Germany.

[JoeGTI]

Thanks Steve, that's good news too!
Latest is that they'll have the new ECU tomorrow to fit to the car. Hopefully fingers crossed they'll stick the old one in the bin and will get the car back on the road ASAP! To be fair, VW have been very good, the VW assist coverage is bloody handy.

To add more drama to the situation, the car is actually traded in! I'm expecting delivery of mk7 GTI very soon, I hope this situation doesn't put a big spanner in that plan.

[TomS_]

It is entirely possible that the ECU was damaged while the tuner was playing with it. Not sure if he was wearing an anti-static wrist strap or anything, but read up about "latent failures" with electronics.

Essentially, ESD can cause damage to integrated components like CPUs, memory etc, which may not result in immediate failure, but rather seemingly random or delayed failure. How long it will take to fail is hard to tell, and it may not happen at all. But its a ticking time bomb.

Without visible evidence the ECU was tampered with (like damaged screw heads, broken seals, etc) it would be difficult to prove this as the cause.

[Keithuk]

They asked me was the car tuned/remapped and I said no. He seemed to take my word for it and we left it at that.

Yeah, its almost 6 months since the tuner had the ECU out,

Who's been telling porkies?

Their diagnostic will tell them if its been chip tuned so there is no escape you saying it hasn't been tuned.

You could have no warranty or a big bill for a new ecu.

[JoeGTI]

They asked me was the car tuned/remapped and I said no. He seemed to take my word for it and we left it at that.

Yeah, its almost 6 months since the tuner had the ECU out,

Who's been telling porkies?

Their diagnostic will tell them if its been chip tuned so there is no escape you saying it hasn't been tuned.

You could have no warranty or a big bill for a new ecu.

Errr thanks... But as I said, it hasn't been tuned. The tuner didn't get it to work on the day. My worry was just will they notice that the ECU was opened up.

[topher]

as long as the tuner put everything back exactly how he found it (including anti tamper bolts!) and didn't leave any obvious marks on the case from prying it open then you'll probably be safe. Even if he didn't seal it properly and water ingress is the cause, by the time anyone in Germany gets round to opening it up, if they even bother for a relatively small warranty claim, you'll be motoring along in your MK7.

[JoeGTI]

Thanks guys... It's reassuring!
New ECU wasn't fitted yet, the dealers are waiting for it to be shipped from Germany. Hopefully tomorrow or Thursday at latest. I won't rest easy till I hear its all ok!!

As a matter of interest, does anyone know what kind of money we are talking for a job like this, out of warranty? I'm guessing thousands?