Sick Golf - What should I do

Carb

Hi all,

Following on from my previous thread on having trouble starting my 2004 1.4FSI Golf, it appears the problem is within the engine management system.

Some background, I got this car 11 months ago, 60k miles on the clock. Due to my circumstances at the time, it was more expensive than it should have been, and I can't really afford to just write it off. There are a number of issues.

• Front brake discs need to be replaced
• To our surprise, the engine has no fan
• There is low compression in one of the cylinders
• The ECU issues

I can deal with the first three as they are mechanical and I know what the mechanic has to do to rectify these.

The current issue with the ECU is that the car starts and runs fine when the software is reinstalled. This will last for a couple of days, and then gradually deteriorate. Typically, if I turn the key in the morning, the car will start first thing, but if I turn it off and try again, the throttle body just clicks. The mechanic thinks the throttle body is ok, as it runs perfect after he runs the software, but when it goes wrong, its with the throttle body.

What complicates it is that the wiring loom has been pulled apart in places and appears to have tape on it, along with the ECU previously been tampered with. The mechanic thinks it is likely that there is a short circuit in the wiring, or an earthing issue, or possibly the ECU itself, but either way, it is looking very expensive to go hunting for the problem.

I can live with spending up to 2k trying to sort all the problems, as I think I will have a fairly good, low mileage car at the end, but on the other hand, I could be throwing good money after bad.

Sorry for the long post. It has been a long saga.

Opinions on what I should do appreciated.

jayok

If the ECU is losing its code, then there's a problem with the ECU! The firmware (software) is normally flashed into the box in in persistent memory (EEPROM or similar).

At a pure electricial level, it sounds like different memory is being used or the chip is fupped and when power is removed from the box it loose it's code. When you reload the code, it's fine, so it it really sounds like the ECU memory. Perhaps someone tried to piggy back on a new "map" chip and made a mess of it.

As an (temporary) fix how about keeping the ECU permanently powered from the battery?

<edit> Not sure of the Golf ECU but perhaps you could get it repaired/checked here: www.autokey.ie

(I've no affiliation, I've just seen other posters used them)

Senna

Have you considered getting a new (secondhand) ECU?
here's one on ebay for £99 EBAY LINK, which isn't a bad price, i would have expected to pay more. You would need to contact them and make sure its correct one for your car etc etc.

Carb

Thanks for the autokey link. It would cost nothing to check them out. Have you ever heard of typical costs for ECU repairs?

What you say fits with what we were told. The mechanic said there was permanent damage beyond what he could work on. He was able to do software work to get around the issues, but I guess the ECU is "forgetting" what he's done.

jayok wrote: »

If the ECU is losing its code, then there's a problem with the ECU! The firmware (software) is normally flashed into the box in in persistent memory (EEPROM or similar).

At a pure electricial level, it sounds like different memory is being used or the chip is fupped and when power is removed from the box it loose it's code. When you reload the code, it's fine, so it it really sounds like the ECU memory. Perhaps someone tried to piggy back on a new "map" chip and made a mess of it.

As an (temporary) fix how about keeping the ECU permanently powered from the battery?

<edit> Not sure of the Golf ECU but perhaps you could get it repaired/checked here: www.autokey.ie

(I've no affiliation, I've just seen other posters used them)

jayok

Carb wrote: »

Thanks for the autokey link. It would cost nothing to check them out. Have you ever heard of typical costs for ECU repairs?
.

The problem is the repair cost depends on the damage. But given you could get a 2nd hand one from ebay as Senna posted and get these guys to program it for your car/keys/alarms, it could work out cheaper?

Carb

Thanks.

It was discussed. Taking into account that we expected a second hand ECU to be much more expensive, we have it as Pan B. The mechanic's opinion was that given the cost, and the risk of getting a bad one, we should hold off until we see if the software would work.

Senna wrote: »

Have you considered getting a new (secondhand) ECU?
here's one on ebay for £99 EBAY LINK, which isn't a bad price, i would have expected to pay more. You would need to contact them and make sure its correct one for your car etc etc.

Senna

Carb wrote: »

Thanks.

It was discussed. Taking into account that we expected a second hand ECU to be much more expensive, we have it as Pan B. The mechanic's opinion was that given the cost, and the risk of getting a bad one, we should hold off until we see if the software would work.

Yeah i would have thought an ECU would be much more, but it depends on if there is demand for certain model ECU's and maybe the TSI ECU's aren't a common problem area?

jayok

Carb wrote: »

It was discussed. Taking into account that we expected a second hand ECU to be much more expensive, we have it as Pan B. The mechanic's opinion was that given the cost, and the risk of getting a bad one, we should hold off until we see if the software would work.

Well, then check with they autokey guys and see what they say, at least you've somewhere to go now with the issue.

George Dalton

OP I have to say from reading your account of the problem that I doubt the diagnosis that has been arrived at.

Maybe you are just not properly describing the work your mechanic has done but it doesn't sound to me like he knows what he is at. Or maybe he knows what he is at and you don't and there is a communication breakdown :pac:

I'm not having a go at him or at you I am just adding in my 2 cents. These kind of problems are pretty much impossible to diagnose over the internet.

George Dalton

jayok wrote: »

Well, then check with they autokey guys and see what they say, at least you've somewhere to go now with the issue.

Autokey will simply say "Bring the car to us and we will have a look at it. If you don't bring the car to us we can't help you"

Carb

George, may I ask what your doubts are. Happy to chat or pm given I don't expect a public opinion from you when you haven't seen the car. I'm aware of your expertise.

In relation to what you said, my knowledge of engines is as good as the mechanic's english so a breakdown in communication is quite possible. However, three mechanics have pointed towards the ECU, and the current mechanic took it from complete malfunction to running perfect. The problem is that it won't stay that way. I guess we're fixing the problem and not the cause.

I'm not expecting a diagnosis from the thread as I appreciate that will only be got in the garage. I'm more concerned that this particular model may be a bottomless moneypit and that I'm throwing good money after bad.

George Dalton wrote: »

OP I have to say from reading your account of the problem that I doubt the diagnosis that has been arrived at.

Maybe you are just not properly describing the work your mechanic has done but it doesn't sound to me like he knows what he is at. Or maybe he knows what he is at and you don't and there is a communication breakdown :pac:

I'm not having a go at him or at you I am just adding in my 2 cents. These kind of problems are pretty much impossible to diagnose over the internet.

Ron Burgundy II

I had to get an ecu repaired on my parents yaris. My dad is an avid readeror car mechanics magazine. They did a feature on ecus, they recommended thisguy ecu doctor.
http://the-ecu-doctor.co.uk/
Unfortunately for me he wouldn’t look at the toyota ecu, due to it being agearbox ecu for an mmt gearbox (sh1t gearbox)
So did some research and found this company
http://www.ecutesting.com/
All you have to do is fill out the online form print it out as well put intoa box with the ecu and ship it over, they will test it for free. They canrepair the ecu but if its of no more use to anyone they have second handreconditioned ecu's.
I have used them they told me the ecu was fine. sent it back to me, and Itold the main toyota dealer it was ok. Toyota dealer felt it was still the ecuso told my parents to buy a new one for €1000 + euro . This part cannot be returned.Well they did and toyota told them a few days later when it arrived that theecu was not the problem!!!

dieselbug

Firstly, Im no expert but its possible that when your mechanic reloads the software its having the effect of resetting all the ecu parameters, car drives fine.

There may be an underlying problem that the ecu is trying to counter by making adjustments to these parameters. If its showing faults for the throttle body, why?

Condemming the ecu should be the last resort after loads of testing.
Jim.

Carb

dieselbug wrote: »

Firstly, Im no expert but its possible that when your mechanic reloads the software its having the effect of resetting all the ecu parameters, car drives fine.

There may be an underlying problem that the ecu is trying to counter by making adjustments to these parameters. If its showing faults for the throttle body, why?

Condemming the ecu should be the last resort after loads of testing.
Jim.

Thanks for the reply. He did mention when the first repair was done, that there was a possibility that the ECU would try to start self diagnosing whatever the issue is again.

It doesn't actually show an error for the throttle body, but it is the throttle body that won't work when the car starts playing up. The mechanic mentioned that the throttle body has its own small ECU and for want of a better phrase, there is a breakdown in communications between the two when the main ECU goes wrong.

As far as I'm aware, there are no errors showing up on the diagnostics (except the fan one for obvious reasons).

Carb

Ok, I now have the funds to go about trying to fix this car.

My preference would be to get a second opinion before I go down the repair/replace ECU route. Can anyone recommend somebody very good in the Northeast.

Alternatively, although it would be a quite a trek, I know George is highly recommeneded here. Is it worth the trip and will he have the expertise/equipment to diagnose the issue and fix if possible (George - feel free to answer that).

Biggest issue is that I now need to buy/rent something whilst getting the Golf sorted.