MK2 GTI filling the intake manifold with petrol

[The Fonz]

Both Gavin and Jmac methods are correct... the resistance method is a quick way to check the continuity of the connection, if you find an issue, Jmac method will pin point it

I would remake all the earth connections...clean any ingress and crap you might find and clean up all the loose wiring in the engine bay making sure that some frayed wire isn't earthed, just to be certain and you would be glad you did it. Failing that, I would most likely say that the issue is with the ECU.... did you get hold of the other ECU you mentioned earlier?

[martinijosh]

Re: MK2 GTI filling the intake manifold with petrol

Not yet, I will be grabbing it during the week.

Sent from my HTC Velocity 4G using Tapatalk 2

[martinijosh]

Re: MK2 GTI filling the intake manifold with petrol










Sent from my HTC Velocity 4G using Tapatalk 2

[The Fonz]

In picture 2 where you have the probe on the rocker cover ( .05V )... just remember it has paint there and will stop the proper connection being made... it should be bare metal connections.. thats whey you get the proper volt reading in Picture 1

From this you can say that the Engine block is correctly earthed but a little bit baffled by the last pic... is that an earth wire??? where does it go too??

What you have to remember is that its the ECU that controls the fuel Injectors to open or close and anything in between... different input signals from around the car inform the ECU on the ratio of fuel to come out of the injector.. i.e the Co2 sensor informs the ECU if the amount of fuel being delivered is to lean or rich... the Airflow Sensor informs the ECU how much and type of Air is coming into the engine etc etc (there are a few)... The ECU then makes its calculations and adjusts the fuel deliver to match

It could be and earthing issue as that sometimes corrupts the signals getting to the ECU or it could be one of the input signals that has gone haywire... Trying a ECU that is known to be in good working order will eliminate a lot of the heartache in finding the problem.. you will then know if its the ECU or one of its inputs

Hope that makes sense

Fonz

[martinijosh]

Cheers Fonz, I'll re check the rocker cover on a part where the paint has flaked off.

For it to be over fueling before the engine is even started I wouldn't think it would be the air flow or o2 sensors acting up as they shouldn't come in to the equation until the motor is running right? I'll pick up that ECU and give it a go. Fingers crossed.

Is there any possibility that it could be the digifant relay in the cabin acting up?

[The Fonz]

MK2 GTI filling the intake manifold with petrol

The Co2 and air flow were just examples of some of the inputs the ECU analyse before doing anything

Just to make sure I read it correctly... Didn't you mention that the mechanic turned the ignition on first and then it started flooding?


Sent from my iPad using Tapatalk HD

[h100vw]

The injectors should not be triggered until the ECU detects the engine rotating. This comes from the hall sender in the distributor.

For fuel to be getting out of the injectors, they are being held open. The way they work IIRC is that there is battery voltage on one side of the injector and the ECU grounds them as calculated. They will be either open or closed. the duration/duty cycle is what is used to alter the mixture. Open longer = richer.

Maybe the injector harness is damaged?

[martinijosh]

The Co2 and air flow were just examples of some of the inputs the ECU analyse before doing anything

Just to make sure I read it correctly... Didn't you mention that the mechanic turned the ignition on first and then it started flooding?


Sent from my iPad using Tapatalk HD

When the ignition is on is when it starts pumping the fuel out, so as soon as the fuel pump primes it start gushing fuel. ECU telling the injectors to stay open would be the issue, but the question is why is it doing that?

This started happening after the battery was run flat, something to do with the battery running flat and trying to start the car must be related. I highly doubt this is a coincidence, although it had been choking on throttle when in warm up loop for about a week before this happened, so who knows.

[h100vw]

Disconnect the injectors and probe the 2 pins. Like I said pretty sure one should be battery volts or 5Volts, forget which. The other should be floating and only go to earth with the engine cranking. The wire that has brown in it will be the ground side, the other is red/black from memory.

There's a think you can buy for check injectors called a noid light. These light up and would flash if the pulses are coming to the injector as they should.

Gavin

[martinijosh]

Re: MK2 GTI filling the intake manifold with petrol

Mk2 that I was getting the ecu from apparently got crushed over a year ago. Good information.


So does anyone know if it could be the relay or not? Its cheaper and easier to change a relay =/

Sent from my HTC Velocity 4G using Tapatalk 2

[h100vw]

Mk2 that I was getting the ecu from apparently got crushed over a year ago. Good information.


So does anyone know if it could be the relay or not? Its cheaper and easier to change a relay =/

Sent from my HTC Velocity 4G using Tapatalk 2

I don't think so. From memory and as I mentioned above on side of the injectors has 12volts with the ignition on and the other side is grounded by the ECU (or a shorted wire?)

Have you looked at the voltages in the injector plugs?

http://www.clubgti.com/showthread.php?254887-K-jet-to-Digifant-wiring

Random digifant wring diagram but they don't vary much. Red wire and brown. The red does come from the fuel pump relay. The brown goes to a brown/white before getting to the ECU.

Gavin

[Jmac]

Ecu does ground the injectors , noid light will tell. Ecu more than likely the drama, should be some on ebay surely, From memory they are still availablee new from injectronics in Melbourne
Jmac

[martinijosh]

Yes I've scoured eBay, there are a few knocking about but I'm not keen on buying something that may be broken out of the box. I'll give injectronics a call, thanks for that.

I'll get out and test those injector wires tomorrow. As long as the battery is hooked up and I test that two connections and get a reading that should tell me that the circuit is complete and running the injectors all the time? I'm wary of turning the key as I don't want to kill half my lawn.

[martinijosh]

double post

[ElliottJ]

Unplug all of the injectors before you crank the car, otherwise you'll just waste all your petrol.