Getting the codes is easy enough by counting the flashes of the check engine light on the earlier TPI units. You can used the ADL link and jumper two connections to get the light to flash the codes and certainly better than nothing. But if you can actually see what each sensor is telling the computer then you can make a better choice on what to replace. You can see if that coolant temp sensor is telling the ECM it's 35 degrees when it's actually running 195 degrees.
You will also see if the IAC or idle speed motor is getting the correct signal.
Last edited by Roy Rodgers; 05/31/2013 8:37 AM.
