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Hi! Trying to start my RS2 that i bought with the engine in pieces. Everything went smooth until start up when i recognized i had no fuel going through the injectors.
These are the sympthoms:
Fuel injectors won't open up when cranking (N83, N31, N32, N33, N30)
Engine coolant temp (G62) Shows an incorrect value of temp, -49c even if i unplugg the sender (tried 3 different sensors with the same result (-49c).
Engine oil pressure gauge (in cabin) was showing 0 before i cranked the oil pressure up to 2,5 bar, now when i turn ignition on it always shows 2,5 bar.. Strange i think, but maybe nothing to do with the ECU.
End of faults.
The list of things i'v checked is long, but hopfully i will remember everything.
Starting with the fuel issue:
1. I have spark at all 5 cyl, therefore i think the G4, G28 and G40 is ok and the J17 (fuel pump relay should pull "wich it does"). If the G40 and G4 wouldn't work i had no spark? right? or is this the first fail i have?
2. I have fuel at the rail when cranking, the connections (Pressure side/Return) are checked so i didn't put them wrong. Fuel pump relay (J17) is therefore working, otherwise the relay woulden't pull?
The J17 needs to see that (Rpm is above 13rpm via G28(Engine Speed sensor), G40(Camshaft sensor) and G4 (Crank position sensor) is syncronised otherwise it would not trigger the earth to relay J17 (Fuel pump relay).
3. Earth (outputs) (INJ 5, 16/55, INJ 2 17/55, INJ 3 34/55, INJ 4 35/55, INJ 1 36/55) via ECU connector is checked to each Fuelinjector to verify that it's not a faulty cable.
4. 12V DC is ok with all 5 Injecotors when ignition is on, so "Holding relay" is ok, and so is the cables, measured to ground on the intake. Also 12V DC when cranking the engine when the J17 puts separate 12V to the injectors.
5. Fuel pump is producing fuel (not yet to measured the pressure or the flow) but it flows gas through the fuel rail.
6. Ground "0V" on the ECU connector have been checked with the ECU connector (off) the ECU, to chassie ground, these are the results: Pin-10/55 0ohm, 14/55 0ohm, 19/55 0ohm, 24/55 0ohm, 30/55 18Mohm, 48/55 0,9Kohm.
From what i have understand the ground 30/55 and 48/55 pin gets their earth from either 10/55,14/55,19/55 or 24/44 pin around the ECU and out again to the sensors.. When i measured on the pins on the ECU 14/55 and 30/55 i get 0ohm, also 48/55 and 19/55 i get 0ohms so the ECU is letting trough the earth connections to the sensors. I have a good Earth connection between all 0V DC connections. But why doesen't the injectors fire?
7- If i do an output test via VAG-COM, N71 (Idling control valve), N75 (Boost control valve), and (N80 Evaporate cole canister) is clicking and seems to work, while the Fuelinjectors won't make a sound. I tried with a set of other
fuel injectors, but it is the same.
Now on to my Colant temp sensor (G62):
1. When i look at the sensor via VAG-COM it shows me the value of -49c.. Of course this is wrong, even if i live in Sweden
I tried 3 different sensors with the same measure.
2. The 5V is ok to the sensor while ignition is on.
3. Earth is ok with the connector to the ECU connected via pin 30.
4. -49c is still present even if i disconnect the sensor, heat the sensor, or changing sensor, nothing helps.
5. There is plenty of other sensors/inputs to the ECU connected to this "earth" circuit, same as the G62, an they are working, for ex Throttle position sender/Idle switch, knock sensor 1,2, Baro metric sensor, coding card slot "driving measures displayed in the dash", and the intake air temp sensor (This i cant look at/se the values through VAG-COM) but i get no fault codes on eiter of the sensors.
Other things: Tried an AAN ECU, with exacly the same faults, so i belive its not an ECU fault. No fault codes from ECU other than "G28 Engine Speed sensor" wich we get everytime when the engine not spinning..
I have read and searched as much as i can, but now im dead in the water. It is sure an easy fault to fix, but hard to find. So now im asking you guys for help.
Been working on my engine rebuild for the last 8 months and i really want to fire up the engine. Have any one had the same issues?
Happy to buy a set of beer to the guy that comes with the sulution to my problems
So let the game begin!
Best regards// André from Sweden
These are the sympthoms:
Fuel injectors won't open up when cranking (N83, N31, N32, N33, N30)
Engine coolant temp (G62) Shows an incorrect value of temp, -49c even if i unplugg the sender (tried 3 different sensors with the same result (-49c).
Engine oil pressure gauge (in cabin) was showing 0 before i cranked the oil pressure up to 2,5 bar, now when i turn ignition on it always shows 2,5 bar.. Strange i think, but maybe nothing to do with the ECU.
End of faults.
The list of things i'v checked is long, but hopfully i will remember everything.
Starting with the fuel issue:
1. I have spark at all 5 cyl, therefore i think the G4, G28 and G40 is ok and the J17 (fuel pump relay should pull "wich it does"). If the G40 and G4 wouldn't work i had no spark? right? or is this the first fail i have?
2. I have fuel at the rail when cranking, the connections (Pressure side/Return) are checked so i didn't put them wrong. Fuel pump relay (J17) is therefore working, otherwise the relay woulden't pull?
The J17 needs to see that (Rpm is above 13rpm via G28(Engine Speed sensor), G40(Camshaft sensor) and G4 (Crank position sensor) is syncronised otherwise it would not trigger the earth to relay J17 (Fuel pump relay).
3. Earth (outputs) (INJ 5, 16/55, INJ 2 17/55, INJ 3 34/55, INJ 4 35/55, INJ 1 36/55) via ECU connector is checked to each Fuelinjector to verify that it's not a faulty cable.
4. 12V DC is ok with all 5 Injecotors when ignition is on, so "Holding relay" is ok, and so is the cables, measured to ground on the intake. Also 12V DC when cranking the engine when the J17 puts separate 12V to the injectors.
5. Fuel pump is producing fuel (not yet to measured the pressure or the flow) but it flows gas through the fuel rail.
6. Ground "0V" on the ECU connector have been checked with the ECU connector (off) the ECU, to chassie ground, these are the results: Pin-10/55 0ohm, 14/55 0ohm, 19/55 0ohm, 24/55 0ohm, 30/55 18Mohm, 48/55 0,9Kohm.
From what i have understand the ground 30/55 and 48/55 pin gets their earth from either 10/55,14/55,19/55 or 24/44 pin around the ECU and out again to the sensors.. When i measured on the pins on the ECU 14/55 and 30/55 i get 0ohm, also 48/55 and 19/55 i get 0ohms so the ECU is letting trough the earth connections to the sensors. I have a good Earth connection between all 0V DC connections. But why doesen't the injectors fire?
7- If i do an output test via VAG-COM, N71 (Idling control valve), N75 (Boost control valve), and (N80 Evaporate cole canister) is clicking and seems to work, while the Fuelinjectors won't make a sound. I tried with a set of other
fuel injectors, but it is the same.
Now on to my Colant temp sensor (G62):
1. When i look at the sensor via VAG-COM it shows me the value of -49c.. Of course this is wrong, even if i live in Sweden
I tried 3 different sensors with the same measure.2. The 5V is ok to the sensor while ignition is on.
3. Earth is ok with the connector to the ECU connected via pin 30.
4. -49c is still present even if i disconnect the sensor, heat the sensor, or changing sensor, nothing helps.
5. There is plenty of other sensors/inputs to the ECU connected to this "earth" circuit, same as the G62, an they are working, for ex Throttle position sender/Idle switch, knock sensor 1,2, Baro metric sensor, coding card slot "driving measures displayed in the dash", and the intake air temp sensor (This i cant look at/se the values through VAG-COM) but i get no fault codes on eiter of the sensors.
Other things: Tried an AAN ECU, with exacly the same faults, so i belive its not an ECU fault. No fault codes from ECU other than "G28 Engine Speed sensor" wich we get everytime when the engine not spinning..
I have read and searched as much as i can, but now im dead in the water. It is sure an easy fault to fix, but hard to find. So now im asking you guys for help.
Been working on my engine rebuild for the last 8 months and i really want to fire up the engine. Have any one had the same issues?
Happy to buy a set of beer to the guy that comes with the sulution to my problems
So let the game begin!Best regards// André from Sweden
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