GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: skcollob_ho on 29 September 2009, 17:47
-
I drove my valver into work this morning, as normal, without issue. It's been sitting outside work until this afternoon when I decided i wanted to go up the shop to get some pick n mix to see me through the rest of the afternoon. I tried starting it, but no joy. It turned over fine, but just wasn't starting.
I called the AA out, and after testing it and trying a new coil pack on it, he said it was likely to be the ECU thats had it, as there was no spark, and everything else checked out fine.
Now my initial reaction was to scream like a 6 year old girl and curse my luck, but when I'd calmed down, i tried to think logically. So here goes with the questions...
1. Has anyone else suffered this fate, and can confirm what the AA man said, which was basically that my car had had a good innings, but all good things must come to an end?
2. If was to remove the ECU, is there anywhere I could take it to be tested?
3. If the ECU is indeed knackered, what will replacing it involve, and how much is it likely to cost me?
Your help is greatly appreciated.
-
i had the same issue last year or begining of this year, turned out to be the coil pack, the car just turned over and over but didnt fire up. check to see any melted plastic on it, check for warmness i think it should get hot or warm when turning car over if its working it will wrm up or get hot dont take my word for it. also get some one to start it during the night and you might see the coilpack glow blue i think.
-
best to check the crank sensor and hall sensor 1st
-
@ sharki, he was carrying a spare coil pack and it wasn't that as there still was no spark.
@ wilde, how would i go about checking that? I'm no mechanic!
-
I would doubt very much that its an ECU problem. Look through you ignition system before doing anything drastic, coil pack, dizzy etc
--Also check immobiliser
-
I would doubt very much that its an ECU problem. Look through you ignition system before doing anything drastic, coil pack, dizzy etc
--Also check immobiliser
I have to disable my immobiliser before I can start my car anyway, so that shouldn't really be the problem, should it?
AA replaced the coil pack with one he was carrying with him, but still no spark.
-
skcollob_ho i just bought a crank sensor cause i thought that was the prob , best bet is to get a mechanic to plug vag com into ur car and see if it shows up any faults . my 1 did the same it turns over fine but no spark at all and ive still not found the prob with it and ive replaced everything that ive been told that could be wrong with it .
-
If it helps knowing, in the last 6 months its had a new coil pack, dizzy cap, leads & plugs.
-
My guess would be an immobiliser issue.
-
@ sharki, he was carrying a spare coil pack and it wasn't that as there still was no spark
Still makes me laugh, aa carry them as standard.
God VWS are sooooooooo relibale.
-
UPDATE:
I had an auto electrician come out to look at it, and he's told me I need to replace the ECU, as there is an intermittent fault meaning that the imobiliser is kicking in after deactivation, and that the ECU was being blocked.
Another fault that kept coming up after being cleared was 'speed sensor' something or other. He did tell me, but I've forgotten exactly what it is. He said he tried to get the code off the ECU for the imobiliser, but he said he couldn't because he didn't have the specialist equipment required.
Do I get a new ECU, transponder & key, or can this issue be sorted out some other [cheaper]way?
-
where abouts are you?
-
West London/Wembley.
EDIT:
Have been looking on Ebay for prices for an ECU, and have come across the right part No. 037 906 024, but the letter after that part No. differ. I have found AB, BE & AE so far. Does it make any difference which one?
-
check vagcat not totaly sure, if you dont have any luck gimme ure engine code + ill check for you later
-
I need all the help I can get mate. It's an ABF.
-
I would have thought that these different numbers were for different engine codes.
If you do replace the ECU, won't the same thing happen if its coming from the immobiliser?
Have you tried totally disconnecting the immob from the car?
-
I have been told that the imobiliser is actually part of the ECU, so cannot be disabled. I did ask the auto-mechanic and he said as much too. He told me that the best option would be to get an ECU from an earlier car, because they didn't have the imobiliser integral to it, so could easily be swapped over.
I've also heard somewhere, that the letters after the part number are only to show that the part has been updated from previous builds. I really need to know if this is going to cause any issues should I be lucky enough to source one, regardless of the letters.
-
yeh i belive immo is built into ecu on mk3s, some of the end nos are just revisions but others are not so prob best to wait+i can get a deffinitive part no when i get home if ya want?
-
Yes please mate. As mentioned, I need all the help I can get with this....I need my car on the road asap!
-
although i think it would be worth checking out crank sensor first, try+ find someone local with vagcom, theres a list on the forum somewhere, although when my crank sesor was plying up didnt show on vagcom
-
But would the crank sensor produce the same symptom as the imobiliser, where the engine turns ans starts on full throttle, but dies within a couple of seconds?
-
quite possibly, the one i have on atm has some bare wires+ when i drive in the wet it dies, then wil start for a few secs with full throttle+ then die again until it dries out
-
yes, if it is a stock imobilser that is causing the problem then it is built into the ECU. Check first and make sure you dont have an aftermarket ECU.
I believe the imobiliser in the ECU can be bypassed, but i carnt remember how and it requires special software.
Have you checked the igniton switch. I carnt remember the wiring for it, but it 'probably' has a wire that feeds the immobilser.
The revision number on the end of the part number is a revision number and shouldnt cause a problem. If you want to double check look up the part number and revision and double check, but in the past i have had ECUs where the revision is alot newer and now problems. If you change the ECU, its probable that it will need coding to your keys. £60 at VW main dealers or find some kind person that has the right software to do it
-
After a bit more digging, and for the benefit of anyone that finds this thread through searching, I have found the following.
ECU P/N: 037 906 024 ** [where you will find the following letters]
The following are imobilised;
AE, AL, BE, BF.
Without imobiliser are;
F, G, AB.
This is probably a stupid question, but I may have located an ECU out of a Seat Toledo that carries the AB revision. Will i be able to transplant this into my valver without issue? If I'm getting it right, then the AB revision doesn't have an imobiliser, thus no transponder, thus no need for the key to be re-programmed?
-
ecu for ABF part no 037 997 024 GX other revisions G, X, AE, DX, BE,
Same part no but BX/SX is the 2E(old 8v) ecu so i doubt they are compatible
-
lol, should be fine outta seat, where did you get the info about immo or not??
-
i believe the immob is located in the clocks, not in the ECU itself.
-
i believe the immob is located in the clocks, not in the ECU itself.
i think you're talking about the transponder thats located behind the clocks.
-
lol, should be fine outta seat, where did you get the info about immo or not??
I was googling! Here's the link...
http://forums.vwvortex.com/zerothread?id=3713684&postid=46359025
-
i believe the immob is located in the clocks, not in the ECU itself.
i think you're talking about the transponder thats located behind the clocks.
no the transponder itself is in the key, the immob is part of the clocks.
-
i think the immo in clocks is mk4s onward not possitive though, yeah the differences are cos the ones i put up are uk+ vortex will be usa, ne way mine are offa etka so should be good
-
i think the immo in clocks is mk4s onward not possitive though, yeah the differences are cos the ones i put up are uk+ vortex will be usa, ne way mine are offa etka so should be good
immob in clocks is mk3 for sure, I know cos I'm currently stuck with mine immobilized! Hopefully tomorrow between Adam and myself we shall decode it :smiley:
-
kk fair hope you get it sorted
-
kk fair hope you get it sorted
cheers dude :smiley: :smiley:
-
i had asimilar problem got the rac out and he checked the immobiliser and a small plug had worked itself loose somewhere under the clocks he pulled it fully off then put it back on and it started and been fine since its located somewhere near the steering coloumn about half way down it may be worth a try
-
if the imobiliser was in the clocks, when people change there clocks (which happens alot) surely they would need programming to your key, which isnt the case as they are plug and play!? Also, the clocks dont show up on vag com which would be strange.
I always thought imobiliser was in ECU, hence the reasoning behind having to have it coded to your keys.
-
My limited research backs that up. The imobiliser is in the ECU, the transponder box is in the dash, either behind the clocks, or behind the glove box depending on the year, and then the wire running to the ring around the ignition barrel. The key has a chip as we all know.
I'm about to buy an ECU with the BE revision, which the seller is telling me came out of a '95 valver that didn't have the transponder box behind the dash, and doesn't have the key.
Will I be wasting my time?
-
Update.
The new ECU arrived today, and was fitted [easy job].
It took a while to get it started, when initially it showed the same symptoms as before, where it would starts for a second then cut out. I floored the accelerator and lo and behold, it started. I revved it up then let it idle and was fine. I even took it for a short spin around the block.
I pulled back into work, and as I open the door, it dies again and won't start!
I thought perhaps that the battery didn't have enough power to start, so I ran some jump leads from a mates car. After a while, it started and idled fine, then as I open the door to move it to the other side of the carpark, it dies and won't start again.
My lunch break is finished, so I can't stay out there all afternoon getting it going.
Does anyone have an idea of what it could be please?
-
hey see when u start the car does it fire up then after a second die? try redlining it and see if its got the same problem as my car, once you get ti to hit the limiter it will work fine, i sometimes have to flip the key on and of and on again to get the revs right up as sometimes it cuts out before i can get right up
-
I read your thread shortly after posting my update. Mine doesn't actually start at all, just turns over. But when it DID start, it had to pretty much floor it for it to start up.
-
yeah its a strange one, usually the ecu cuts out because it knows something is wrong, and if you havent been doing any engine conversions lately it may be a bad earth on ur engine?