To those of you that helped me with my coolant sensor problem, thank you. But now i got another problem. I recently replaced my A.I.R. Pump on my 1993 Camaro Z28 to alleviate a MIL code 26 on my 1993 Z28. The MIL code no longer showed up, and i reset the computer to clear the code.

The problem i have now is that the cooling fans come on too late, and turn off too early. You see, the fans now come on at like 240 degrees, and turn off at 200 degrees. The fans do not stay on long enough to cool down the engine, and the turn on too late to keep the engine safe. I don't even begin to know where the problem resides. Is it the computer? Is it the fans? Does the computer need to learn after it is reset? Is it normal operation after the computer is reset? Is it a sensor? Did i reset the computer correctly? As you can see i have many questions. I have already replaced the coolant temperature sensors in the water pump and the head.

If anybody can help me with my problem i will very much appreciate it. Thank you.

 

This is the stock fan temp programming:

The computer will command primary fan "ON" at 226º and "OFF" at 221º and secondary fan "ON" at 235º and "OFF" at 230º.
(Primary and secondary fans on a 1993 -later models have low and high speed fans)

Allowing for a little discrepancy in your temp gauge, you are probably normal. If you want them to come on sooner, have the computer reprogrammed or get a fan switch to control them. A search should find lots of info about fan switches.

Also make sure you have not removed your air dam.

 

So that's the normal programming? Then did my car have a problem before? The fans used to come on at about 200 degrees and then cooled down the car to about 180. Now the car does not do this and the car does not even cool down in traffic and especially in stop and go traffic. The car stays between 200 and 240 and this is in the red zone of my temperature gauge. So if this is the correct programming, then what is my problem???? I hope someone can help me.

 

Make sure you have bled out all the air from the cooling system. You might also want to get a scanner, so you can see what temp the computer is seeing. It will also show when the fans are turned on. That way, you will see if the computer is operating correctly. I don't know about the way it was previously working, unless something had already been altered.

 

Very true. I had no idea that there was a difference between the two sensors until I hooked my laptop up to the car. On my car, 226 is in the red. And I'm pretty sure 240 is when the computer sets the check gauges light. At least that's when I looked up from my laptop and noticed the light was on, could be anywhere from 237 to 240 I guess.

Stock, the LT1 was designed to run pretty hot- since I can't stand staring at the needle that high, I have a 160 stat and a manual fan switch. Now it stays at about 1/4, even in this NC heat. Your best bet is to invest in some scanning equipment or else do some cooling mods to see if your cooling system is up to the task of cooling off the LT1. It took me almost a year to get the system how I like it. I ended up soldering all the connections under the hood- I even had to remake all the wires for the fans since I had messed them up in a previous attempt at a manual fan switch.

 

Alright. So the car is supposed to be running hot. But 200 - 240 degree hot and in the red???? Well I will make my attempts to cool the engine down the way I want. I will check for air in the system and I will also be reseting the computer again.

If someone knows how to best reset the computer on a 1993 Camaro Z28, please let me know. Also, I want to install a 160 degree thermostat. I want to know if on the 1993 Z28, do I have to reprogram the computer to allow the 160 degree thermostat to work properly? Or is it a straight bolt on? Next, I would like to buy a scanner, but I do not know what product brands are available. If someone can give me brands and prices I would much appreciate it. Lastly, does the Hypertech Programmer and other such products act as a scanner as well?

All your help is very much appreciated.