'96 A4 12V no spark problem (camshaft & ECU)
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'96 A4 12V no spark problem (camshaft & ECU)
No spark on any of the cylinders.
While testing the camshaft sensor per Bentley instructions, not getting any power to the sensor from ECM / ECU
Wiring is good. Bentley says replace ECU.
Vagcom reads engine module but no codes.
Anything else I can test to make sure it's the ECU?
Thanks
While testing the camshaft sensor per Bentley instructions, not getting any power to the sensor from ECM / ECU
Wiring is good. Bentley says replace ECU.
Vagcom reads engine module but no codes.
Anything else I can test to make sure it's the ECU?
Thanks
AudiWorld Super User
Joined: Jun 2008
Posts: 2,284
Likes: 100
From: Fallbrook, CA
If the cam sensor wasn't working, I'd expect a fault code. The ICM on the airbox is the spot where low-current trigger signals change to higher-current ignition coil currents, so start there. Make sure the connections are clean, and also check the connector for the ignition coils, which is behind the driver's side cylinder head. I don't have a schematic available right now, but I'll check to see which pins should have what voltages at the ICM.
I could be wrong, but believe that three of the wires in the ICM connector (four wire) which go to the three coils are hot when the ignition is switched on. The other wire is grounded, and the transistors in the ICM switch each coil wire in sequence to ground, from control signals coming from the ECU, to fire the plugs.
I could be wrong, but believe that three of the wires in the ICM connector (four wire) which go to the three coils are hot when the ignition is switched on. The other wire is grounded, and the transistors in the ICM switch each coil wire in sequence to ground, from control signals coming from the ECU, to fire the plugs.
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I had a similar issue almost exactly a year ago. I couldn't get any spark and for the life of me, couldn't figure out what it was. I even bought a used ECU and a couple of used ignition control modules. I do have a Bentley and was following the directions as stated.
Nothing worked.
What the problem ended up being was somehow the timing jumped. I had done a timing belt job a couple of years before that, but hadn't had a problem since. What I ended up doing to notice the timing was off, was to put the car in service position and try to put the camshaft alignment tool across the two camshafts. Lo and behold, they didn't line up. I simply loosened up the timing belt, moved the camshaft back into time, and reattached the timing belt.
Nothing worked.
What the problem ended up being was somehow the timing jumped. I had done a timing belt job a couple of years before that, but hadn't had a problem since. What I ended up doing to notice the timing was off, was to put the car in service position and try to put the camshaft alignment tool across the two camshafts. Lo and behold, they didn't line up. I simply loosened up the timing belt, moved the camshaft back into time, and reattached the timing belt.
Thread Starter
AudiWorld Junior Member
Joined: Oct 2010
Posts: 32
Likes: 0
I had a similar issue almost exactly a year ago. I couldn't get any spark and for the life of me, couldn't figure out what it was. I even bought a used ECU and a couple of used ignition control modules. I do have a Bentley and was following the directions as stated.
Nothing worked.
What the problem ended up being was somehow the timing jumped. I had done a timing belt job a couple of years before that, but hadn't had a problem since. What I ended up doing to notice the timing was off, was to put the car in service position and try to put the camshaft alignment tool across the two camshafts. Lo and behold, they didn't line up. I simply loosened up the timing belt, moved the camshaft back into time, and reattached the timing belt.
Nothing worked.
What the problem ended up being was somehow the timing jumped. I had done a timing belt job a couple of years before that, but hadn't had a problem since. What I ended up doing to notice the timing was off, was to put the car in service position and try to put the camshaft alignment tool across the two camshafts. Lo and behold, they didn't line up. I simply loosened up the timing belt, moved the camshaft back into time, and reattached the timing belt.
I tried another ECU and another ICM. Still does not turn over.
I do not get voltage at the CAM connector even with the other ECU.
Fuel comes to the rail but stops as i'm cranking. Every time i switch ignition ON and OFF, fuel pours out. Vagcom Engine output sequence operates the Fuel relay.
How can i check if the timing is off?
thanks
AudiWorld Senior Member
Joined: Oct 2003
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This is how.
What I ended up doing to notice the timing was off, was to put the car in service position and try to put the camshaft alignment tool across the two camshafts. Lo and behold, they didn't line up. I simply loosened up the timing belt, moved the camshaft back into time, and reattached the timing belt.
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