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Quote:
Originally Posted by seventythree View Post
Not to hijack this thread but since we have some IMS experts here, I can't resist to ask:

My 2002 base is reading out of spec cam deviations, -7 & -8 respectively.
The deviations are constant, with no fluctuation, at idle or any other RPM.
Both deviations get slightly larger with engine warm-up.
There has been no junk in the oil or the filter (I've checked at every oil change).
There is no start up noise indicating failed tensioner(s).
The engine is running fine!

What is cam deviation? Camshaft, both intake and exhaust, deviation relative to crankshaft?
How is the deviation measured?
What could cause cam deviations to change?
How can it be corrected?
Can the car be driven in the meantime?

TIA
Cam deviation values are how far off they are from ideal (zero degrees). The values are measured by the DME using the crank and cam position sensor signals and a simple algorithm. Why they are out of spec can come from several different issues (or combinations of issues): Stretched chains, worn tensioner paddles, worn or sticking tensioners, problems with the VarioCam system, the cams simply not being correctly timed in the first place, weak or dying position sensors, etc., etc………

When the cams are too far off their ideal timing, you definitely give up performance, and generally speaking, these problems do not get better with age. All of the above conditions are eminently fixable, just takes some time and money to sort it out. Time to start doing some in depth diagnostics………..
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Old 03-14-2012, 11:47 AM
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