: Northstar Temp sensor & Lock up converter ?'s

02-10-12, 06:37 AM
Hello, Looking for some guidance here. I have a 2005 Northstar motor in a kit car and have some questions. I need to hook an external temp sensor to the motor, I have an eletric gauge. I believe the the temp snesor on the motor is on the front of the head, correct? There is a yellow and black wire coming from it, Which wire can I splice into to get a temp reading?

Also, I don't beleieve the converter is locking up, going down the highway at 65MPH I'm taching about 2500RPM. Is there is a way to run a switch to control the lock up in the converter? As I said this is in a kit car, the motor runs great with the excpetion of this. I'm sure there is some error codes and that is the reason the PCM is not signaling it to lock up.

Any help or thoughts would be greatly apreciated!

Thank you!

02-10-12, 07:31 AM
This question is more appropriate for the folks that frequent the engine specific area of the site. I'll move the thread over there, but it will also remain visible in STS where you originally posted for a few days.

02-10-12, 08:10 AM
Thank you & sorry about that!

02-10-12, 11:23 AM
The temp sender is on the rear end of the right cylinder head - down under and to the right of the throttlebody. The sensor in the front of the right cylinder head cam cover is the CMP - CaMshaft Position sensor - used to send piston reference signals to the ignition system and injector trigger in the PCM.

You'll need a 2005 shop manual - GM, not Chilton's or Haynes - to find the transmission/PCM wiring diagrams - as well as figure out the signal voltage to set the TCC; the vehicle speed signal determines TCC lockup (> 43 mph, road loads, < some specific throttle opening %)