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no ignition signal


MK413

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Hi all,

 

I have an Audi TT 1.8 link G4+ plug in, I've had no issues with it and got a base map tuned on it by my tuner awhile back however I still had work to do before I was ready to get it fully mapped. I've completed everything I needed to do and went to attempt to start the car and I have no spark. I have 12v supplied to the coils as I should however upon cranking there is no voltage coming from the ecu on the signal wire. I've continuity tested everything and all the wires are as they should be which leads me to believe its an issue with the ECU. The ECU is getting power and shows no errors in PClink. Anyone have any clue what could be happening? I've also checked to make sure both my crank and cam position sensors are functioning and they are all good. 

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4 hours ago, MK413 said:

I have 12v supplied to the coils as I should however upon cranking there is no voltage coming from the ecu on the signal wire.

How are you testing this?  The pulse will only be approx 3ms long, once every 720 deg so you wont pick it up with a multimeter or anything like that.  You may see it with an LED test light.

Does the coil spark if you use the ignition test function?

Are you getting realistic RPM showing in the software when cranking?

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On 6/10/2020 at 5:54 PM, Adamw said:

How are you testing this?  The pulse will only be approx 3ms long, once every 720 deg so you wont pick it up with a multimeter or anything like that.  You may see it with an LED test light.

Does the coil spark if you use the ignition test function?

Are you getting realistic RPM showing in the software when cranking?

I was using a test light. I also was testing with the spark plugs in and looking for a visual spark. The coil does indeed spark using the ignition test function however I am not getting anything on the tac when cranking. I’ve just replaced the crank sensor with a brand new one to rule that out and have used the trigger scope to ensure a signal is getting delivered and it is. I’m still just not getting a signal to the coils when attempting to crank it over however. 

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Your cam sensor isnt working, it is just a flat line.  The ECU will not spark until it has synced and it wont sync without a cam sensor.  So you need to diagnose that.  Either the sensor has failed or there is a bad connection somewhere.

A hack you could do to test is on trigger 2 settings you can set sync mode to none, then the ecu doesnt need a cam signal to spark.  It wont start everytime like this without a cam sensor but you will get a spark, approx 50% of start attempts it will be sparking on exhaust stroke rather than compression.

vZxrRtW.png

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12 hours ago, Adamw said:

Your cam sensor isnt working, it is just a flat line.  The ECU will not spark until it has synced and it wont sync without a cam sensor.  So you need to diagnose that.  Either the sensor has failed or there is a bad connection somewhere.

A hack you could do to test is on trigger 2 settings you can set sync mode to none, then the ecu doesnt need a cam signal to spark.  It wont start everytime like this without a cam sensor but you will get a spark, approx 50% of start attempts it will be sparking on exhaust stroke rather than compression.

vZxrRtW.png

That would explain it, Thanks! I hadn't realized that the link required both signals as the factory ecu only requires the crank position sensor and hence removed the cam sensor from the lost of possibilities. I appreciate the help!

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