Golf Mk3 - ABD code - Cutting Out problems

[unkleGsif]

Hi there

having moved further from work to live with my Mrs, I have started to re-develop a really worrying problem......


Randomly, and with no apparent warning or signals, the engine will just cut out. It was doing this about a year ago, but I thought I had sorted it by just relocating an Immobiliser module slightly. I really seemed to work, as its been fine since last year.

Now however, its starting to do it again, altho FAR worse. What pointed me to the immobiliser was that the indicators would shut off as well. Also, there is an unmistakable "click" from the area under the dash where the module is, it would then restart after having poked and prodded around

I really need this car to be reliable, as I take the Mrs to work, commute myself, then use my car for work meetings tec, so probably will be doing 100+miles per day


I have looked around both here and elsewhere, but all I can seem to come up with is problems with Gti's etc... this is a 1.4 ABD

Litterally ANY pointers or helps would be really usefull
Regards
G

[Golf tdi Hal]

Hi, all I can suggest is it might be a relay that feeds the ECU.
The circuit board inside gets hot when the relay is 'on' and the circuit tracks open when they warm up and expand. When the engine cuts out or is switched off, the relay cools down and the circuit 'makes' again.

When you moved the immobiliser module, I'm guessing you disturbed the relay sufficiently to make it work again.

[unkleGsif]

Thanks for that Hal... sounds like it could be it!

This morning on the way to work I had taken off the panel to access the fuse/relay box by my right knee. Through a process of elimination, each time it cut out (8 this morning ) I was able to hold each relay and isolate which one as the engine cut out... the far right one seems to be it, as I can feel it click just as the engine dies, and it responds to friendly "taps" best, allowing the car to start.


Not a great deal of time to source another from a scrappy today, so may have to try the dealer

G

[Golf tdi Hal]

The relay (marked 109 in my diesel...) is about £12 from the dealers.
Don't forget the one from the scrapyard may have the same problem, or develop it !
If you know an electronics engineer, tv repair man or someone who knows what they are doing, it is easy to 'remake' the solder joints inside the relay box.

hope its the answer.

[unkleGsif]

well, no progress having replaced what I thought was the faulty relay.
like i said yesterday, i could feel this relay clicking as the engine cut out, so without knowing what it was (no manuals or wiring diagrams) i replaced with a new one from TPS (Trade Parts Service).

turns out it was the fuel pump relay, and that the problems persists....


where abouts is the ECU relay located on a 1994, 1.4 ABD coded Golf?
Still, not all bad, no breakdowns on the way to work this morning, just traffic


G

[unkleGsif]

having done even more research, and compared what I have read with what is on my car, I dont have a No' 30 relay.... so that completely rules out that one out



SO, back to square one
this is really doing my head in, and if its not sorted in a week, i am gonna torch the bloody thing

Seriously, ANY suggestions would save about 10years worth of ageing from my furrowed brow!


G

[Crasher]

No the ABD does not have an ECU relay but it does have a fuel pump relay at position 12 (bottom right) and this could be the clicking. What could make the fuel pump relay click is a faulty distributor hall sender, they are very prone to this problem on the small engine models with the distributor on the head. When the hall sender signal stops, the ECU turns off the fuel pump relay. When it cuts out, does it re-start straight away or do you have to wait.

[unkleGsif]

depends entirely on seemingly random factors.....

sometimes it will cut out and basically bump start itself back to life before I heven have a chance to put the hazard lights on, sometimes it will just need a restart once stopped, and sometimes i will have to wait up to half an hour


is the hall sensor actually inside the distributor? ie replacing the whole distributor suffice, or is the sensor somewhere else and just plugged in to the dizzy?


ta
G

[Crasher]

The hall sender is inside the distributor. It is possible to buy the hall sender but there are two types, you have to identify the distributor version to get the correct one and it is time consuming and tricky to change plus it costs more than half the cost of a complete unit. I will only fit an exchange distributor but I am up against the clock and so the time taken for me to fit the sender means it costs more than buying even a genuine VW exchange unit, VW part number 030 905 237 AX which costs around £100 and comes complete with a new cap and rotor including a two year parts and labour warranty. It is a slightly specialised job to fit though, you can’t just slap it on and be off, it needs setting up using not only a timing light but also a diagnostic computer. I think it is possible to buy these units exchange elsewhere for less but the quality is variable at best.

[unkleGsif]

back to square 1 on this one.....
new distributor fitted, and while running smoother in general, it still cuts out!

i have noticed now (maybe because other symptoms have been erradicated, there was a very loose fuse that i identified as the fuel pump fuse) that it cuts out most frequently when there is a significant load on the electrics.... lights on, radio on, heater on etc.... and that when it cuts out, the indicators stop working and the ignition lights on the dash go out


i think basically there were 2 or 3 problems at play here....
1, fuel pump fuse..... fixed
2, hall sensor.... fixed
3, as yet, unidentified electrical problem

i have checked all earthing points that i can find (1 under coolant resovoir and one on a largeish junction above the clutch housing), and all seem to be ok

loosing my rag on this now

G