hello all, new to the site, i just got my 94 firebird with the lt1 sunday and i have a question. my fan wont turn on so i checked the fuse and relays and its all good but im not getting a signal to the relays so i assume its the sencer so were is it? i looked around but was unable to locate it any help would be good thanks

There are two temp sensors. One is in the driver's side head which sends the engine temp to the PCM, the other is on the top of the waterpump, and is the sensor used for the cold idle speed, and some other functions like injector pulse width enrichment. The fans are controlled by the PCM and not directly by a sensor. In the 94 early variant and late variant, the fans come on at 242 F and turn off at 221 F. If the fans are failing to come on, then there would be a warning SES light turned on in the instrument cluster, or both fans could be frozen and stopped dead, or the engine is not warm enough. If the A/C is turned on, both fans should come on immediately. If they don't, then the PCM and the both sensors should be suspected. One of the common problems in this is that someone pulled one or both sensors and installed them with sealant. That's a NO NO! Drain the coolant, keep it clean for reusing, pull both sensors and clean the threads. If you can see sealant of any type gooping out around the sensor while it is installed in the engine, then that is what someone did--you must clean it off on the sensor threads and the threads in the waterpump and left side head before the sensor will work.

If this does't work, then suspect the PCM as defective, but try everything else first.

Hope this helps

ok well i dident no thay turned on so high so i just took out my bypass and put back in the relays and let it get hot and thay turned on so ya i guess i just thought they would come on way sooner. thanks for all the info

That was an easy fix. Good thing that you figured it out. However, everyone on this forum will tell you that the fan turn on temp is way too high and should come down. A Hypertech Power Programmer will allow you to set the fan turn on temp to much lower temps, like down to 195 F and off at something like 180 F--there are several choices. The only reason GM set the fan turn on temp so high was to burn off impurities in the oil and allow them to advertise an extended oil change interval. It's best to keep the engine cool.

how much hp do you gain on a stock lt1 with that programmer? what else can you change with it?

Bless their pointy little heads---they claim all sorts of power to be gained, but the real truth is that there isn't much that can be done to "improve" the OEM programming for power. The PCM is already tuned to just about max--so figure only a couple, certainly less than five hp. The real advantage is that the fuel injector shut off limits can be changed, the top speed cutouts can be changed (depends upon the speed rating of the tire) and the fan turn on/turn off limits can be changed. Also, you can adjust the speedometer for larger than stock tires if you want and change auto shift programming if needed, even adjust for different final drive ratios.

However, if you do some serious work to your engine, then raise the rpm limiter you will get some serious hp increases, and that is where the fun begins.