Mk2 GTi 8v 1989 - Petrol in oil sump

[Shabumba]

In major need of help here!!

Recently had a friend take a look at my Golf, due it it randomly not firing up.

After a few attempts we noticed the exhaust was leaking out petrol (and eventually oil!). Cut a story short, turns out there was a massive overload of oil in the engine (approx 3 inches OVER ther max line on the dipstick, wasn't my doing either...) so there is now somehow oil coming through the air filter, and alarmingly neat petrol in the oil sump.

The engine will only seem to start when the injectors are DISCONNECTED and it uses whatever fuel is in the engine, we noticed aswell that fuel doesn't seem to stop getting pumped in. Other than it possibly being the Pressure Relief Valve, gotta say I dunny have a f**kin' clue what's gone wrong.

Anyone heard of this before??

[Dolly]

sounds like injectors are pissing out fuel?

[i_am_me]

is it a digifant injection or k-jet?
if its a digifant chances are your ecu has blown(common fault)
check the earths that go from the battery-chassis-gearbox and the one that goes from the rocker cover to the coil.
then replace the ecu
(ecu`s are just plug and play so any mk2 golf digifant ecu will plug straight in)

[richard.thomas]

Hi,

Are there any updates to problem?

I have a possible blown ecu symptom as well.  (digifant 1.8 8v)

I have inherited the car so i have no history on its state so am starting from scratch.
There is spark, although only yellow and engine timing(flywheel/dist/cambelt) has been checked.  Fuel pumps are running.

Is there any other way to check ecu fault other than seeing if cylinders are flooded?  Can i carry out some resistance or voltage checks to confirm?   Are injectors all wired together and operate in tandem?  I can only see two cables going to the injector unit.

Are you also saying that any digifant ecu can be replaced by any ecu, regardless of year or part no:?
I believe i have a pre 90 car.  Maybe a later ecu would be more robust?

Thanks for any thoughts.

[clipperjay]

Digi's are all sensitive to voltage spikes I would be cleaning up all earths first before even testing another ECU why do it unless you solve the issues of why it got damaged in the first place?
On the other hand they are all getting a bit long in the tooth already!
No testing a ECU unless you have a diagnostic jack plug to see whats happening.
Any Rallye and G60's ECU are technically 8V digi's but their mapps are all too rich for a stock 8V. You can can tell a G60 ECU as the stickers are purple and Rallye ones are Green stickers, Not sure what if colour is relevant as I've never had a stock 8V?
In the past the only thing I did was to check for continuty of the plug to each sensor on the engine bay to establish if the loom itself was good.
I still have Two spare ECU's but all off a Rallye and G60 Corrado!

I've only come across two things that made the car shat itself
ECU
Hall Sender
If you have a VAC pipe from the ECU apprently it must be dead on 1 meter in length.

[Oet]

If you have cranked it over a lot and its not started (say ecu blown) then you have probably got bore wash too, petrol seeping through piston rings, and into bottom end of engine. Drain it all, the oil will be watered down and no good now. At least starting again means you will have the correct level of clean uncontaminated oil.
If you were running really rich you would probably end up with a lot of fuel in the exhaust, and due to overfill of oil, some oil too.

[richard.thomas]

Hi japperjay,

Do you have ecu plug layout that you could send me so that i could check wiring also?

I checked volts on injector main plug, it shows 12volts here with key on.  Does this mean ecu dead?
Are all 4 activated at the same time?

Does the digifant use a oxygen sensor?  If so any ideas on where to find it??


Slightly off topic but maybe an option!
Ive seen megasquirt type ignition systems on the web.  They seem to suggest they could be used on a digifant.  Anyone had any experience of these?

Thanks for your help.

[Shabumba]

is it a digifant injection or k-jet?
if its a digifant chances are your ecu has blown(common fault)
check the earths that go from the battery-chassis-gearbox and the one that goes from the rocker cover to the coil.
then replace the ecu
(ecu`s are just plug and play so any mk2 golf digifant ecu will plug straight in)

It's an injection.
ECU sounds very possible, we've checked nearly everything else.
Drained all the oil out completely and topped it back up, still without any joy.
Fuel is making it to the engine and back out to the tank.
We can only think of it being that it continuously builds pressure and won't switch off when full, hence it starting fine without the injectors connected.
It was suggested that it could be borewash but I i was assured that it wouldn't solve the problem. Seems certain to be a fueling issue.
Any ideas as to where i could locate the pressure valve on this model?

[clipperjay]

Hi japperjay, Me? Clipperjay?

Do you have ecu plug layout that you could send me so that i could check wiring also? I do but pointess unless its all connected up best to send ECU off for checking stealth racing might offer this service someone on here might aswell?

I checked volts on injector main plug, it shows 12volts here with key on.  Does this mean ecu dead?
Are all 4 activated at the same time? Impossible to tell. I prefer to stick them into plastic coke bottles then tape them up really good to see if they are all working and have a good pattern!
Its more than likely you have a broken wire loom to the injectors the plastic casing I would check for melted or broken injector loom!

Does the digifant use a oxygen sensor?  If so any ideas on where to find it?? Yes its on the air intake pipe!


Slightly off topic but maybe an option!
Ive seen megasquirt type ignition systems on the web.  They seem to suggest they could be used on a digifant.  Anyone had any experience of these?

Thanks for your help.

[Santiago]

I think you need to read what it says about 'Maintenance of older Digifant vehicles' in this Wiki article: http://en.wikipedia.org/wiki/Digifant_Engine_Management_system unless you have done already.

The earthing problem particularly.  It's a common occurrence for the 'gearbox earth' to be removed when clutch/box work is undertaken, then it is forgotten about rather than reconnected before attempting to start the engine.  Corrosion could also account for an inadequate connection at this point. If that earth isn't doing its job for whatever reason, some of the return current from the starter motor when cranking will try to go back to the battery via the ECU, which doesn't do it any good at all.

UK Mk2 Digis don't have an oxygen sensor in the sense of a lambda sensor.

Most likely you need another ECU, not to be tried out until any earth fault is found and fixed.