c18xe limits at 4500 rpm help please

[DavebGsi]

Yes I've changed everything and tried 3 different crank sensors, and still coming up with RPM signal on the scanner

Do you have he engine running when you do the scan, these cars come up with RPM sensor as a fault when the engine isn't running and you do a scan.

does it pulll ok up to 4500, or lack of power?