Remember the two guys who used to be on NPR---Click and Clack, the Tappet brothers? They had a one hour radio show called Car Talk? In the days of carbs and chokes, they loved it when a GM car or truck owner would call in with a 'hard starting when cold' problem. They would laugh and joke about the 'choke pull off' on the carbureted GM engines failing. Replace the Choke pull off device and it would start cold and then run well. Now with the fuel injection and PCM controlled engines, it is the ECT sensor that acts like a bad 'choke pull off' device. Hard starting when cold and poor fuel economy.

 

I have disconnected it for now.
And it runs great.
Wtf??

 

Maybe that means that you have found the problem. I trust you have ordered the new ECT sensor and are getting real to install it.

 

Yes. I just got parts the other day. Will install tomorrow.

 

I have the same question for a 94 S10 Blazer. I've got a ridiculously high idle, burning way too much gas, floods if I hold the key when starting (from a cold start) and my temp gauge stays at 100. I was also told it could be the IAC senser.

 

Well the install is done. I got AC Delco parts through Rock Auto. The coolant sensor, radiator cap, and thermostat came to $49.77 after 2 day shipping charges. Not bad.
It was necessary to remove the wheel to access the coolant sensor. Also needed a very long extension, swivel joint, and a 19mm deep well socket. It's best to start threading the new unit in with your fingers as far as you can before torquing it down with the ratchet. There is some type of anti seize on the threads so you will encounter some resistance as you go. Careful not to overdo it. And be sure your electrical connection clicks into place.
Test drive indicates successful repair. 😁
Am happy.

 

Congratulations. Happy to hear a successful repair, looking forward to getting mine done.
Did it solve the other issues as well?

 

Drove it quite a bit, on the interstate at high (legal) speeds, and in city traffic, and let it idle for a good 20 minutes in a parking lot. It exhibited no signs of trouble. Now to tackle something else on the list.....

 

Green Blazer, thanks for the initial follow up and a later follow up on the repair. That is great feed back which will help many who are having the same problem. Thanks for taking the time and effort to pay it forward. Including the source and price of repairs is helpful info. There is always a pending list! Jim

 

I'd like to mention the location of the ECT sensor can be either on the intake or the drivers head. Depends on the year and I don't remember off hand what year it moved. 98 is on intake, 01 is in head, so either 99 or 00.
Doesn't matter, it's still the same identical sensor.