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rjpiselli
02-08-2017, 01:29 PM
2000 a4 2.8 auto.

How does vcds read engine speed (rpm) and how does the gauge cluster read rpm?

At 70 my tach says 4100rpm but vcds says engine speed 2900.

So they obviously have different sources. Which would be more reliable, or how would I determine which is the accurate rpm reading?


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down_n_dapper
02-08-2017, 03:20 PM
Vcds is always more accurate as it reads the sensors themselves. RPM is measured off the flywheel, check the coding of your cluster, could be interpreting the rpm wrong

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rjpiselli
02-09-2017, 05:58 AM
I'll check that out. Thanks for the tip!


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rjpiselli
02-09-2017, 08:40 AM
Well that seems to be the issue. Coding was for a 4 cylinder turbo. Changed to 6 and now tach matches vcds reading.


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down_n_dapper
02-09-2017, 02:15 PM
Well that seems to be the issue. Coding was for a 4 cylinder turbo. Changed to 6 and now tach matches vcds reading.


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Glad that worked for you!

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