still can't get help or an answer to my problem. took off the oem P225/60/R16 and installed a set of custom 225/55/R17" tires and rims. Checked a supplied chart from Discount Tire and made the comparisons of the 2 sizes so I wouldn't affect my true road speed. Well this change has affected the indicated in dash speedometer speed, as compared to my readout on my GPS by about 30-35%. I>E from a dead stop, the speedo doesn't even start moving till after 15 mph. At 60, with a GPS readout of 60 mph, speedo reads 40mph. I have disconnected the negative battery terminal and thought this would allow the wave length, read by the tranny speed sensor, to adjust and re-calibrate everything. Didn't happen. Ordered a new speed sensor and installed. Still no changes after another battery disconnect. Just can't believe that, with above changes made, this is coincidental to anything. Believed the ecu would recognize the tire change and new rotation and make any and all new adjustments. What am I missing and where have I failed. Any suggestions, comments solutions would be greatly appreciated.
Anyone know of a obd scanner capable of reading and having the capability to make the changes directly to the ecu?
