How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Randall Your Own Question
Randall, ASE Certified Technician
Category: GMC
Satisfied Customers: 12886
Experience:  ASE Master Tech, 32 Years Diagnostic and repair,Electrical specialist
Type Your GMC Question Here...
Randall is online now
A new question is answered every 9 seconds

The temperature warning light of my GMC truck came on today

Customer Question

The temperature warning light of my GMC truck came on today when the engine was still cold. I replaced the thermostat but the light is still on, and now the engine races for 60 seconds at startup before kicking down. I need the get the warning light off, with lower idle speed at startup. What should I do?
Submitted: 1 year ago.
Category: GMC
Customer: replied 1 year ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Customer: replied 1 year ago.
My credit card has already been charged $5. I am willing to pay another $34 for a solution that works, but I do NOT want to subscribe to any ongoing monthly program. Please send instructions for one-time payments of $5 plus $34 or please cancel my request and refund the $5, thanks.
Expert:  Randall replied 1 year ago.

Hello, My first thought without tests or being there etc,, you have a failed, The ECT is what sends signals to the computer to tell if engine cold or hot. Kind of works like a choke, If bad? is will try to go to high idle as in choke mode persay, No way for me to say if sensor is bad or the plug or for that matter the ECM , but in most cases? it is a filed sensor. I cant remember all locations but it is at front of engine, I think close to T stat, Screwed into the engine and will have a Yellow/Black wire going to it