Fan Kicks on at what temp on 87GN??
- Thread starter 87GNTTOP
- Start date
around 165+-
- Joined
- Nov 24, 2001
- Joined
- Nov 24, 2001
Just click the link i posted, we were probably posting at the same time
BW
BW
A little background on my situation. I replaced the temp sender that communicates with the ECM this morning with a new one. I replaced both relays with new ones.
I still cant get my low speed fan to kick on. The fan will only go on at 200', which means its the high speed fan.
Both relays are getting power at the red wire going in. The high speed fan show power comming out of the relay when it gets to 200'. No power comming out of the low speed relay.
This problem, started when I installed my new chip for my injectors. Is there a slim possiblity that it could be chip related?
I still cant get my low speed fan to kick on. The fan will only go on at 200', which means its the high speed fan.
Both relays are getting power at the red wire going in. The high speed fan show power comming out of the relay when it gets to 200'. No power comming out of the low speed relay.
This problem, started when I installed my new chip for my injectors. Is there a slim possiblity that it could be chip related?
chrisgarrett
Registered Member
- Joined
- Jun 2, 2004
Chris, that was a great link. I was able to check the relays and confirm that they are good.
It is looking more like its going to be at the chip or maybe the ecm. This problem started when I changed the Chip and injectors. So, it could possibly be the chip. Eric, is sending me a replacement chip in the mean time to see if thats it.
Thanks
It is looking more like its going to be at the chip or maybe the ecm. This problem started when I changed the Chip and injectors. So, it could possibly be the chip. Eric, is sending me a replacement chip in the mean time to see if thats it.
Thanks
Even if you have a 160 thermostat and a radiator and fan thats doing its job, the motor can still run hot. With my turbotweak smog chip, the motor ran at over 200 degrees even with the 160 thermostat and the fan working, and with a good radiator. Normally I run at 162 degrees with my extender chip. So your chip may be determining the fan turnon point.
When I got my car, the low speed fan was barely working. I knew it wasnt the fan switch on the intake manifold because it was switching over....the fan was just barely spinning. I popped the relays off the inner fender and popped the connectors off, and all the pins and sockets were packed solid with 20 year old die electric grease. I spent about an hour with ronsonol lighter fluid, a pick, some q-tips and a blowgun, and got everything sparkling clean. After that, my low speed fan worked great. It spun much faster and everything worked when it was supposed to. So before you do anything, make sure to clean all those contacts out. Not just the connector, but the pins on the relays as well. With a poor connection, the amp draw will go really high and can start burning things out in your electrical system, and will put a huge workload on your alternator.
Make sure all the contacts are like new, first, and then move to other things. When the low speed fan relay turns on, the circuit goes through the fan resistor. When it switches the high speed relay, the resistor is bypassed and it puts full power to the fan. Some people will run a wire straight across the fan fuse, so that when the low speed fan relay turns on, it goes straight to high speed. I got a weird vibration at high speed since the fan isnt perfectly balanced, so instead of just running a straight wire to completely bypass the resistor, I ran a 50 watt, 1 ohm resistor to slow it down a bit. It almost runs at full speed now, but not all the way, and I dont have that vibration and its not working the 20 year old fan to death.
So between the cleaning of all the contacts, the 1 ohm 50 watt resistor, and the autozone F-Body radiator, my engine always runs cool, even in stop and go traffic, whereas before it was always overheating.
When I got my car, the low speed fan was barely working. I knew it wasnt the fan switch on the intake manifold because it was switching over....the fan was just barely spinning. I popped the relays off the inner fender and popped the connectors off, and all the pins and sockets were packed solid with 20 year old die electric grease. I spent about an hour with ronsonol lighter fluid, a pick, some q-tips and a blowgun, and got everything sparkling clean. After that, my low speed fan worked great. It spun much faster and everything worked when it was supposed to. So before you do anything, make sure to clean all those contacts out. Not just the connector, but the pins on the relays as well. With a poor connection, the amp draw will go really high and can start burning things out in your electrical system, and will put a huge workload on your alternator.
Make sure all the contacts are like new, first, and then move to other things. When the low speed fan relay turns on, the circuit goes through the fan resistor. When it switches the high speed relay, the resistor is bypassed and it puts full power to the fan. Some people will run a wire straight across the fan fuse, so that when the low speed fan relay turns on, it goes straight to high speed. I got a weird vibration at high speed since the fan isnt perfectly balanced, so instead of just running a straight wire to completely bypass the resistor, I ran a 50 watt, 1 ohm resistor to slow it down a bit. It almost runs at full speed now, but not all the way, and I dont have that vibration and its not working the 20 year old fan to death.
So between the cleaning of all the contacts, the 1 ohm 50 watt resistor, and the autozone F-Body radiator, my engine always runs cool, even in stop and go traffic, whereas before it was always overheating.
I have narrowed it down to the chip or the ecm being the culprit. The chip is new and the problem started during the time of the new chip and injectors. Maybe just a coinsidence?? Maybe not?? Eric is sending me a replacement chip, but he seems to think it is one of my drivers in the ecm. So if the chip dont cure it, I will try a different ecm. Keep you posted. And thanks for the info.
You might consider upping the wattage of that resistor. The fan draws around 7 amps and at 12.7V, across a 1 ohm resistor, you're dissipating somewhere around 90 watts if the fan free-wheels. I'd recommend at least a 100 watt resistor if the 1 ohm resistance value works for you.
FWIW, if the driver IC in the ECM goes out, it usually burns, so you'd smell the burning chip in the box. Quick test, unplug the low speed fan relay and place a test light across the brown wire and the green wire. Run the engine up to temperature. If the ECM is good, the light will turn on at the pre-programmed temperature in the chip. That will eliminate the ECM as the culprit. Even if you use the stock chip, run it to 210 to check for operation.
Im not sure, but if I had to guess, it sounds like the fan's rpm's are dropping about 200-300 or so. I just double checked. I forgot that it's a .01 ohm resistor, not 1ohm. And the resistance is much higher with the factory resistor, and its also a 50 watt unit I believe....also on memory, but I could be wrong. I made a thread about this awhile back, and some other people had input as well.
.01 ohm is neglegible as I wouldn't think it would slow the fan noticeably at all. The OEM resistor is 0.3 ohms. Could your resistor be 0.1 instead of 0.01 ohm?
A good resistance range would be probably between 0.25 to 0.5 ohms. You might consider an adjustable wirewound power resistor, and could play with the settings to get a good balance between minimal fan speed and maximum low speed cooling.
A good resistance range would be probably between 0.25 to 0.5 ohms. You might consider an adjustable wirewound power resistor, and could play with the settings to get a good balance between minimal fan speed and maximum low speed cooling.
