Scirocco Central

Hi all, basically I was involved in a crash about a month ago and the front end of my car was pretty stoved in. The garage rung me last week and said my car was ready to collect so I went in for it. It looks spot on from the outside and I was really happy with it. I drove off and noticed a major lack of power but was hopeful this would sort itself after a while. It didn't and the car was back at the garage within an hour! It wouldn't rev, basically got to 5000 but no higher and when it reached this it wouldn't change up until I backed off the throttle (dsg) it also through up a check engine light. so basically no power and dodgy gear change. The garage have told me they took it into a local vw garage for diagnostics (I called vw to check this and they confirmed they had it but couldn't discuss it with me as they were under contract with the garage??) and found nothing. The garage has now investigated the problem and found a cracking in the turbo housing. Basically I want to know if this cracking would cause the dsg to play up? It would obviously be a reason for the lack of power but don't see how it would affect the dsg? And also how have vw found absolutely no fault codes?? It doesn't make any sense to me at all! Anyone have any opinions on this?? All views welcome just after some feedback really!
Cheers, John

Somebody must have a view on this?!

How big wa the hit, did the engine move in the impact? Was the front of the car pushed onto the gearbox/ engine?

It was a decent hit, the police woman told me to take my tax disk and cash it in as I wouldn't be seeing the car again! The broke a mount at the back of the engine, the garage have said that this caused the turbo to collide with the steering rack and crack along with the oil pipe to the turbo. I appreciate all this would cause a lack of power but how vw haven't found a fault code is confusing me!!

I cannot be certain about all the details but as an electronics designer I do see a great deal of poor system understanding and consequent fault finding in many realms...

So, we cannot be sure what VW garage did or did not do. Let's give them the benefit of the doubt. It is possible that no faults occurred at low - moderate revs. Even if the revs went up to 5,000 - the car would most likely be tested at a standstill. This means that the fuel burn, exhaust gas volume etc would be much less than when you actually drive the car.

What faults might we expect to see with your cracked turbo? Presumably it's not some giant hole by virtue of the fact is was not spotted straight off. When the engine is cool (or less than fully heated) at low revs/power the gap may not allow too much leakage - the car is "normal" (almost). At high revs whilst running and hot, there is expansion to open the gap and more pressure to push the gas out.

The only sensor that would "see" any of this is the lambda sensor which looks at fueling compared with exhaust gas. The car's engine management is mapped for a properly functioning turbo whilst yours would have a reduced boost pressure. This means that the car would appear to become over fuelled at high revs so the lambda sensor will feedback the over-fuel condition - the engine management wants there to be more air before greater quantities of fuel are injected.

The punch line is that the DSG is not "independent" of the engine - the light on the dash and the sensor information will "advise" the DSG of revised limits. The fact that the fuel delivery has to be backed off at such revs and the lambda is unhappy is a reason for the system to flag an "unidentified" fault. There is no specific sensor for a cracked turbo - so all sensors will report as OK in themselves.

I may not be 100% spot on but it should be broadly in the right realm.

Thanks for your reply, all that does seem pretty plausible and hopefully a new turbo will sort the problem out. I have no idea about which sensors go where and do what function but it seems strange to me that something as big as a turbo failure wouldn't show a fault code, there was literally no power and it was like driving a 1.2! But as I said I have no knowledge on engine electronics and what your saying does make sense to me so I will see how I get on once the turbo is replaced. Thanks again for your reply.

John

I agree with bluepeter i.e the fact that they might have tested at low revs, hence the fault wouldnt reoccur. However, once john_w hit the higher revs, the system should have stored a fault code! At least one that acknowledges the EML went on at some stage. I find it almost implausible that such a big fault would not be recorded.

My only suggestion would be if you know anyone with VCDS/VAGCOM close to you, get them to do a check when you get the car back. It might help reveal some of the underlying things.

It might be the fault with the turbo/engine that made the DSG misbehave, and once this is fixed, all will be well.

In my opinion: I am surprised that your car was not written off with such an impact. I am not sure I would want my insurance fixing a car which has so many components move out of place. Can you get someone independent to give the job a once over? Don't let the insurance company take you for a ride

From what I've read you say it through up the engine management light, if this is the case then there would be a stored code which will show past and present faults, even if the light turned it self off the codes will still be stored until you physically turned it off via a diagnostic tool. So I find it odd that vw say there is no fault codes, seems like they are hiding something :-/ The boost fuel system has various sensors, as you have a boost leak I suspect there would be a map sensor code, eg 'requested boost not met' you also may have air flow codes which indicate a boost issue. As for the dsg change, the box uses throttle position as well as a host of other sensors to decide when to change gear, if you have a huge lack of power then I'd assume your accelerator pedal would be pressed quite far down, this would in turn make the gearbox think you are requesting more power and therefore it will hold the gear or even change to a lower gear. I would was say it's quite plausible that the lack of power is causing issues with the gear shifts.

Hope this helps :-)

Shak

I would ask for an inspection of the engine and gearbox too based on the fact it was clearly impacted in the accident, looking for witness marks, cracks in the casings , damage to the mechatronics unit which mounts to the front of the gearbox.

Cheers for the replys, the check engine light came on when I picked it up and so it should have been on the system for the vw guys to check when it went in to them! I have spoken to vw though and they won't divulge any information as they are under contract with the garage doing the work. I am also very surprised it wasn't a write off as they must have spent 7-8k on it now! How would I go about getting an independent check done? Will my insurance pay for this or is it something I have to do off my own bat? This being my 1st ever crash and insurance claim I am a bit unsure what to do but I don't really trust the garage doing the work anymore!

Thanks again, John

john_w wrote:Cheers for the replys, the check engine light came on when I picked it up and so it should have been on the system for the vw guys to check when it went in to them! I have spoken to vw though and they won't divulge any information as they are under contract with the garage doing the work. I am also very surprised it wasn't a write off as they must have spent 7-8k on it now! How would I go about getting an independent check done? Will my insurance pay for this or is it something I have to do off my own bat? This being my 1st ever crash and insurance claim I am a bit unsure what to do but I don't really trust the garage doing the work anymore!

Thanks again, John

Where abouts are you??

Shak

john_w wrote:Cheers for the replys, the check engine light came on when I picked it up and so it should have been on the system for the vw guys to check when it went in to them! I have spoken to vw though and they won't divulge any information as they are under contract with the garage doing the work. I am also very surprised it wasn't a write off as they must have spent 7-8k on it now! How would I go about getting an independent check done? Will my insurance pay for this or is it something I have to do off my own bat? This being my 1st ever crash and insurance claim I am a bit unsure what to do but I don't really trust the garage doing the work anymore!

Thanks again, John

Hmmm Good question about the independent check... You could go to a VW garage and get them to inspect it, the person HAS TO BE a specialist and someone who knows what they are talking about (some people might suggest an indy VW specialist, as they are more street wise).

Or, the AA do those prechecks for 2nd hand cars, and they might be able to spot some of the more obvious faults.

Speak to your insurance about them footing the bill, if not, keep the invoice and the list of faults they find and push for a claim-back. You will have to hold a solid footing on this one.

I'm in Lancaster!

I will have to wait til I get it back before I even think about getting it checked. The garage have said it's about a 2 hour job to change the turbo and that I might have it back tomorrow. Does anyone know if there is a running in period for a turbo? If not I will take it for a good drive and see if anything lights up, then look into an independent check.

Cheers, John

We're a vw specialist based in Bolton, if you want bring it down I can give it a check over for nothing, just so you have piece of mind :-)

Shak

Ah really?? That would be absolutely awesome! Like I say I don't have the car back yet, may get it tomorrow but I've heard that before!! How much do you charge for a dsg service? I'm in need of one as mines never been done and has 65k on clock!

Thanks again, John

john_w wrote:Ah really?? That would be absolutely awesome! Like I say I don't have the car back yet, may get it tomorrow but I've heard that before!! How much do you charge for a dsg service? I'm in need of one as mines never been done and has 65k on clock!

Thanks again, John

Yeh that's fine pal, we charge £149.95inc vat for a dsg service, that includes genuine oil and filter

Shak

That's a really good price, I've been quoted double that on occasions! I'll let you have a look at the car once I have it back and if it's all alright I will book in for the service. I'll be in touch anyway.

Cheers,John

john_w wrote:That's a really good price, I've been quoted double that on occasions! I'll let you have a look at the car once I have it back and if it's all alright I will book in for the service. I'll be in touch anyway.

Cheers,John

Not a problem pal, just pm me when you are ready :-)

Shak

Quick update, just been up to see the car. The old turbo was out and apparently was a nightmare to get at and remove?!? The guy had taken the wishbone and drive shaft out of one side to get at it! I don't know whether this is required or not?! The old turbo housing had basically bent (where 2 parts are pressed together, looked like a bearing) under the impact and the turbine had seized! They are on with getting it back together now but don't know when that will be!

Cheers, John

So let me get this right, the engine moved enough in the impact to bend the turbo manifold, yet they failed to spot or check this during the repair, ?

The only item the manifold could impact is the bulkhead, so did they repair that? Would mean stripping most of the dash/interior out to do it properly.

I'm sorry to say this, but I would seriously be looking for other impact damage, bulkhead, engine and gearbox casings, driveshafts and suspension ( get a 4 wheel alignment check done) Or even damaged wiring. Sounds like the job was done to a price to me.