[Closed] Molgrips car #4 - A New Hope

What exactly is the problem?

Well if he knew that ..... etc

renton - Member
You were given some good advice by myself and others about the problems in your previous thread!

Did you follow any of it?

Don't be silly, this is Moly. These threads are more inellectual exercise than decision making process... 🙂

Try a defibrillator
as you guessed I have no idea, bit like where your car is 🙄

Have you tried a bike fit?

There's an indy VAG place near me Molgrips. (Lichfield).
Called Mckenzies.
I've no experience of them myself but a phone call is only a few pence.
You never know...

There's also a pretty clued up chap on the Ford Galaxy owners club website, who works for an Audi dealership in Stafford. I'm just thinking, it being VAG etc. I think they ask you to donate a small amount to join & post/message etc, but if you drop me an email I could send the chap a message for you. FGOC.co.uk

Thanks folks. Renton I did follow your advice, problem is that the only way of finding out what ECU part I have is the sticker on the unit, and it's partially scratched off!

Current thinking is that there is a fault inside this ECU, based on what this guy and VAG support said.

Trail rat - if I buy a new ecu I am £500 down. If I buy a new car I am £5,000 down. Still don't see it.

Did you speak to the dealer as I suggested in your other thread.

DOH EDIT IGNORE ME !!!

and you are guaranteed an ECU will fix it ? if so what you still fannying around for ?

if it doesnt youll be 500 quid down and still have a ****y car.

£656 plus other fixes so far with no certainty.... But I do see why you are persevering, it's just I wouldn't.

I'd be looking for a cheaper way to put winter tyres on it if I were you to cut some costs.

and you are guaranteed an ECU will fix it ?

I can buy a shitload of parts and still be better off than if I bought a new car trail rat.

I am fannying about to make sure that it really is the ECU and to see if I can get it fixed for less than £500.

could also buy a shit load of parts for less than 5k and still have a driveway ornament + have to spend 5k on a new car.

only worth persevering if its a classic that deserves saving imo. this is a passat like many of the other hundreds of thousands on the road (except this ones broken)

your passats been more hassle in the last year than my 1000 pound frontera which needs a set of tires to keep it legal for the next year;)

It's not helping him! I am the same, I've spent a grand around 4 years ago due to a dodgy abs pump that the mechanics thought were at fault at the wheels.. cost about 300-400 more than it should have but I kept going til it was sorted. I started so I had no intentions of quitting. Glad I did as it's done thousands of miles since. Good luck with finding the right person. Maybe joining a vw forum/passat forum might help a bit?

No officer, I've no idea how it happened. It may have been the ECU...

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That's it! You need to park it on Fenchurch street,London.

Molgrips, have you tried contacting a Tuning / Remap company (Not a VAG Specialist)? They interrogate and rewrite ECU's and as such they should be able to create an ECU code from your chassis number (Which gives the Vehicle Specification). As long as your ECU is good they can re-code it correctly, oh and you may have more performance / economy too.

The quick way would be to email one of the sponsors on any VW / Audi Forum that provides remapping services.

could also buy a shit load of parts for less than 5k and still have a driveway ornament

It still drives. I can't afford a new car, I'm not spending thousands of pounds to save hundreds. Your logic is rubbish. So stop it!

Konastoner - yeah.. that's a good idea, I just have no idea where to find a really good knowledgable outfit who's willing to help me fix my non-fast car, rather than some dodgy boy racer outfit who won't be interested unless I want moor powerz. I'll have a look at one of the forums, ta.

You're missing the point that when you buy the new car, you actually SELL this one...

So you may lose £500 not £5000 as you've sold your PoS car that doesn't work properly.

[i]You're missing the point that when you buy the new car, you actually SELL this one...

So you may lose £500 not £5000 as you've sold your PoS car that doesn't work properly.

[/i]

That kind of logic won't work with Moly, as he's already 'decided' what the answer is. 🙂

He could have been anyone of a number of Managers I've had over the years...

I think the issue is;

Would fixing the car make it sell for more than the cost of the repair (if you were to sell it) than selling as is?

So if unfixed it would trade in for £X and fixed it would go for £X+£500 then it's worth spending no more than £500 fixing it. Otherwise, logically, you should just walk away.

But then there's the emotional 'I won't be beaten by this' thing that we all do that spoils it.

The thing is though there's the extra expense of a new car. They aren't free.

what was the original problem with the car, before the idiot mechanic did the unnecessary ECU swap?

was that the gearbox oil (possibly) problem, with gearbox doing some limp-home mode?

Original problem was crazy electrical weirdness like brake lights staying on when the car was off and the engine not stopping when I got out and locked it.

It was caused by water in the trailer control module in the boot. I found this out and fixed it myself after having been fobbed off and given the run around for months by the mechanic.

Gearbox was fine until the ecu was changed. I checked the oil last night incidentally, it's still runny and it's also quite pale in colour still which is good.

So, youre initial issue was a result of CAN bus errors, caused by water ingress into the TrCM. This had a knock on effect (due to the CAN data corruption) into other control modules. I assume the TCU was changed erroneously because the transmission was going into limp mode when it "lost" its CAN data exchange.

There is, in reality, unlikely to be a fault with the "new" ecu (assuming it is roughly of the correct type. All these modules are now "coded" to your car, and that includes the firmware (the operating instructions) and the calibration (the operating variables) data. These devices are also fully 'adaptive' and aim to learn your driving style and modify their shift points etc to suit you. As such, if this adaptive data has not been properly reset, the TCU may do funny things, or if the coding is incorrect, it may also not operate exactly as before.

If it were my car, i'd want to have the following done:

1) an independent review of the CAN data to ensure the bus is viable (using software that records the raw data stream and identifies arbitration and bit errors)
2) Talk to VW Uk to identify the exact variant coding for your car
3) Get the TCU flashed with this s/w and the adaptive tables cleared
4) Once 'fixed" data log some important parameters to validate the fix is working!

molgrips - Member
The thing is though there's the extra expense of a new car. They aren't free.

You buy the new car for the exact same price you sell the rubbish one for.... therefore theres's no extra expense ?

You're more intelligent than this usually.

Two options for you to try, I have worked with both and was very happy.

Pendle Performance. VAG ecu specialist. Writes his own software, owns a rolling road for development. Highly regarded on the VW T4/5 forum. Ask for Martin. He id dpf removal development on my T5.

Shark Performance, as above. Mapped a Skoda VRs for me.

Both have agents across the uk and both know a hell of a lot about ecu's.

Good luck and with car electrics, I feel your pain.. !

Just goes to show, electrical systems in cars are now far too complex for the average garage to diagnose and fix.

So, do I have this right, its a little confusing to me still, all the electrical weirdness has now stopped, but you are left with an ecu (which may or may not be compatible with your particular model of passat) which is causing the gearbox control to be sub-optimal?

Basically yes. There are two problems - one is that it insists there's a short to ground on the inlet manifold flap position sensor, which there isn't; and the gearbox shifts slowly. But there are no gearbox fault codes.

You buy the new car for the exact same price you sell the rubbish one for.... therefore theres's no extra expense ?

Well there are a few issues with that.

1) I've had my car a while, I know it's had a good life, I know it's been driven well and not abused, and I know it's had new injectors recently (a recall).

2) I really really hate shopping around for cars privately. I mean really. I'm bad at it, and I'm likely to be ripped off one way or another.

3) How the hell do I sell a car that's not working properly? Lie?

That's it! You need to park it on Fenchurch street,London

Probably be cheaper to buy a new car.

As I have said before; I would get the engine problems fixed before spending any time/effort sorting the gearbox problems. You may well find that the slow shifting is due to problems with the engine. I presume that it is the upshifts that are slow? The bit of the upshift which I suspect you are saying is slow will be the time taken for the engine speed to reduce from the speed in the start gear, to the speed of the new gear. This speed reduction is done by the gearbox telling the engine to reduce its torque. If the engine does not / cannot reduce its torque sufficiently, you will get a slow shift. If there is a fault with the engine, then it may restrict the amount of torque reduction that is available to the gearbox. The engine tells the gearbox how much it can reduce the torque (from which it would be able to calculate the 'shift speed') so it may be the case that the gearbox has no fault codes, because as far as it is concerned, it is operating within the confines of the parameters available to it.

An ECU change may be the best bet (if you have had a reflash), but I would say that the best people to ensure that you get the correct model ECU and ECU software / calibration would be a VW garage. I'd be surprised if a 3rd party had access to all the detailed info about the spec of your car that VW UK would (although I could be wrong).

I have a lot of experience of the transmission on your car (DQ250), so whilst I'm not claiming to be an expert and to know exactly what is wrong with it whilst sat at my PC, and that I know best, that is my advice to you.

3) How the hell do I sell a car that's not working properly? Lie?

We buy any car dot com 🙂

I understand your thoughts, your logic and even some of your processes. But there comes a time when you just throw in the towel and cut your losses, even if you get hurt a little at the time. Otherwise you're there fretting, worrying and having abusive conversations with people for week after week, month after month and STILL the car doesn't work right... then you go through it again the month after.

PErsonally... i'd cut my losses, take the hit and walk into a new/replacement car.

As I have said before; I would get the engine problems fixed before spending any time/effort sorting the gearbox problems.

Thanks for a good post bamboo, I think you are right. The VAG support said that whilst it was possible that the ecu problem was causing the dsg to be in 'restricted' mode he'd never seen it happen. But yes I think I should do as you say.

Up and downshifts are both slow. It seems to be taking a long time for the new clutch to engage, and as you say the rest of the gearbox seems to be adjusting to deal with that. When downshifting in manual mode, the car ends up in neutral for a second before slipping the clutch into the new gear exactly as if you were slowing down gently driving a manual.

I keep thinking of things it could be - bad gearbox oil, worn clutches etc, but the fact remains it only started when the ecu was changed, and it's remained consistent every since withouth degrading.

My current theory is that there's a fault in the ECU itself that was not picked up by the suppliers - the short to ground on the flap position sensor is actually inside the ECU - it's certainly not outside it. I've tested the wiring with a continuity tester, one lead clamped to the engine and touching the other on each pin in turn. One is connected to ground, but it's the brown one so it's meant to be.

I tried tackling the suppliers originally, because the part had a 12 month guarantee, but they seriously fobbed me off. They said that the guarantee did not apply because the original fault had not been fixed before the ecu was fitted. This is clearly bullshit because the original fault was not related to this current fault in any way. The other issue is that my contract and hence the guarantee is not with them, it's with the mechanic.

Can you not buy/borrow a known good correct ECU and then fit it, test and either sell back on or give back to who you borrow it from ?

Ah yes, WBAC.. how COULD I forget 🙂

£2,785.

Can you not buy/borrow a known good correct ECU and then fit it, test and either sell back on or give back to who you borrow it from ?

Nah, it has to be exactly set up for my exact car.

Depends on your morals then for selling to a dealer 🙂

It isn't unheard of that the physical ECU can cause a problem that causes a false diagnosis; I'd really be looking getting the ECU changed if you can. If you are going to go to the expense of changing the ECU, doing it by a reputable source (i.e. VW) is likely to be your best bet.

You could try swapping your ECU as weeksy suggests, but you may find that there are software routines that match the ECU to the car, so doing this may not work and could muddy the waters further. I'm not 100% sure on this point though; I write the control algorithms and don't get involved in that type of stuff if I can help it.

Well I know that the local specialists charge £400 +VAT for a refurbed ECU, and the dealer will be £1000-£1500.

I do wonder what we/you'd do if you got one... and had the exact same issue...

Why the hell are you trying to diagnose a problem when you're clearly not a mechanic or VAG/ECU specialist?! If the guy that should have fixed the problem made it worse you should have manned up at the time and got him to sort it out. Sounds like that's too late now so if you don't want to sell it as is you need to bite the bullet and hand the keys to someone who knows what they're doing.

Sometimes you need to accept your limitations and allow someone else to sort things out for you. You appear to be staggering from one half arsed attempt to another.

I work in IT and fix things for a living. A large proportion of the work I do involves listening to well intentioned people tell me what they think the problem is. These people generally have absolutely no idea what the problem is or how to diagnose it, let alone fix it. They can of course describe the symptoms well, which helps develop a problem statement. Once I've listened to them I tend to take an analytical approach to the problem based on a clear problem statement, a good understanding of how the system works (or should work), and several years of very appropriate experience.

You might think you're helping by trying to work out this issue but what you really need to do (IMO of course) is take a step back and let someone who knows what they're doing look at it.

I do wonder what we/you'd do if you got one... and had the exact same issue..

Give up!

Sounds like that's too late now so if you don't want to sell it as is you need to bite the bullet and hand the keys to someone who knows what they're doing.

Lol.. find me someone and I will! I also work in IT, and I don't like it when people clearly guess at what the problem might be and ask me to hand over thousands of pounds, when their logic is full of flaws. At least the garage yesterday were honest and open, outlined their reasoning and between us we drew conclusions.

Garages are not full of experts who understand all the intricacies of ECU systems. They are full of people who like to change bits and charge you for it on the off-chance it'll work.

He tried that yesterday

The bloke charged him £156 to say "dunno mate"

Tonyd speaks a lot of sense.

You need to figure out a budget; 500 max then go to a independent with the risk that they may not have all the tools/info available to them that VW would.

If you can afford 1k, then go to a dealer. If not, sell to somebody you won't feel bad selling a faulty car to; we buy any car etc.

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Lol.. find me someone and I will!

I also work in IT, and I don't like it when people clearly guess at what the problem might be and ask me to hand over thousands of pounds, when their logic is full of flaws.

Garages are not full of experts who understand all the intricacies of ECU systems.

They are full of people who like to change bits and charge you for it on the off-chance it'll work.

The guy that looks after my 10 year old BMW is a BMW specialist. If it develops a problem I don't strip the engine and try to fix it, I call him and describe the symptoms. Sometimes he'll tell me to bring it in, sometimes he won't. The last time we spoke I told him about a funny noise when I push the clutch in, sounds like somethings going to break. He listened to it, sucked his teeth, and told me it's an expensive fix but other than the noise should be OK for a few years yet so not to worry. Not everyone is trying to rip you off.

The thing is I've lost all confidence in garages over the years. So I'm going to learn as much as I can myself. I don't see a problem with this. If I talk to an expert and they really do know their stuff I'll listen to them. But I'm not going to blindly hand over cash any more. I don't have enough for that. The suggestions from yesterday's garage were either a new ECU, or a new clutch and DMF for the gearbox problems at a cost of a grand, and a very low confidence of a fix. Er yeah thanks but no thanks.

Anyway, I've emailed the dodgy geezer, who wants to see what I wrote?

So I'm going to learn as much as I can myself. I don't see a problem with this. If I talk to an expert and they really do know their stuff I'll listen to them. But I'm not going to blindly hand over cash any more.

Anyway, I've emailed the dodgy geezer, who wants to see what I wrote?

1. What are you going to do then ?

2. Sure... why not 🙂