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Diagnosing a Bad Cam Position sensor...

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Old 02-20-2009, 12:05 PM
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Default Diagnosing a Bad Cam Position sensor...

I unplug it and it runs absolutely the same as plugged in. WTF?
Old 02-20-2009, 12:19 PM
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Default Doesn't that tell you something?

is there a procedure in the Bentley for diagnosing the actual sensor?
Old 02-20-2009, 12:34 PM
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Default Yeah. The car will run off the crank sensor.

Rob, every time I have had a misfire code with that cam code, it has been a mis timed engine. I would be happy to ship you a good sensor to test. I suggest checking cam timing.

AWM engines are known for shearing the cam gear....
Old 02-20-2009, 12:37 PM
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what does "shearing the cam gear" mean?
Old 02-20-2009, 12:39 PM
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Default The cam gear has a key built into it.

I have replaced two AWM engines that have sheared this key. Both had galling on the foremost cam journal, leading me to believe the cam seized or had great resistance and ...kerblewie.
Old 02-20-2009, 01:37 PM
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2nd...from experience
Old 02-20-2009, 01:55 PM
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Default completely sheared? like the cam gear was spinning lose? or just sheared and jammed?

i wonder what they changed in the design.
Old 02-20-2009, 02:20 PM
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Default First one I remember seeing sheared was about five years ago.

The cam gear was turning blue from the heat (they are normally a bronze color)... it looked awesome. Oh that car got a new engine too.
Old 02-20-2009, 02:24 PM
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Default The key completely separates from the cam gear.

It is generally seen on 1.8T engines that have suffered catastrophic engine failure.

I've seen what Joey is describing on at least half a dozen 1.8T engines over the years.
Old 02-20-2009, 02:45 PM
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Default Personally, I blame it on extended oil change intervals.

But I have zero evidence this is true.


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