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BMW E46 (M43B19 1.9 Petrol Engine) Crank No Start
- etseale
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1 year 6 months ago #66920
by etseale
BMW E46 (M43B19 1.9 Petrol Engine) Crank No Start was created by etseale
Hi,
First of all I must say that I'm just starting to learn the craft, so please accept my apologies for stupid questions. Most likely the whole thing is obvious, but I just don't yet know enough.
Anyhow ... I have a BMW E46 with 1.9 gasoline engine. As the title suggests, we have a crank no start condition. I have gathered some evidence and it has well ... enough to have a good reason not to start ...
1. The Fuel rail pressure is 3 BAR (about 43PSI) which it should be according to TIS
2. Spark is present
3. Injector feed and pulse is present
4. Cylinder wall scoring in at least 3 cylinders.
5. Compression is high and uneven (should be 10 BAR, but is 14, 16, 15.5 13.5. I assume that is due to cylinder wall scoring causing oil presence in cylinders (or is it???)
That is all fine, but the interesting point is this ... When I crank the engine watching the RPM on the OBD, it sometimes drops to 0 and comes back to normal values. The question is: is this RPM behavior normal or is this some kind of grounding / wiring issue at ECU or ... ? The sensor is brand new one.
Here are some of the gathered oscillograms:
Coil one ignition primary VS AMP compression test
Secondary ignition gathered with wire wrap on plug wire #1
Probably should continue with getting Crankshaft position sensor VS OBD readings tomorrow, but out of garage already.
First of all I must say that I'm just starting to learn the craft, so please accept my apologies for stupid questions. Most likely the whole thing is obvious, but I just don't yet know enough.
Anyhow ... I have a BMW E46 with 1.9 gasoline engine. As the title suggests, we have a crank no start condition. I have gathered some evidence and it has well ... enough to have a good reason not to start ... 1. The Fuel rail pressure is 3 BAR (about 43PSI) which it should be according to TIS
2. Spark is present
3. Injector feed and pulse is present
4. Cylinder wall scoring in at least 3 cylinders.
5. Compression is high and uneven (should be 10 BAR, but is 14, 16, 15.5 13.5. I assume that is due to cylinder wall scoring causing oil presence in cylinders (or is it???)
That is all fine, but the interesting point is this ... When I crank the engine watching the RPM on the OBD, it sometimes drops to 0 and comes back to normal values. The question is: is this RPM behavior normal or is this some kind of grounding / wiring issue at ECU or ... ? The sensor is brand new one.
Here are some of the gathered oscillograms:
Coil one ignition primary VS AMP compression test
Attachment not found
Secondary ignition gathered with wire wrap on plug wire #1
Probably should continue with getting Crankshaft position sensor VS OBD readings tomorrow, but out of garage already.
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