grill block delete
 

since the weather has warmed up, I have noticed in my crx ,that the fan will come on when I shut the engine off, and the fan will continue to run for quite a while. the coolant level is full, and the temp gauge is not registering hot. I am assuming my grill block is causing the fan to run longer than normal. I removed the grill today to and will see if this fixes the problem. I also recorded my worst mpg this last tank. maybe the alternator is working harder to recharge the battery, or under hood temps are too high.

Maybe a faulty thermostat or temperature sensor? Or replace the grille block with a smaller, partial one.

I removed the grill block, and now the fan does not come on after engine is stopped. I will keep track of mpg and see if it hurts or helps. If I needed to, I could wire the
fan to a manuel switch.

What are you using to measure the coolant temperature? The dash gauges can be quite inaccurate, so having some other means to control temperature would be good. This may explain why your fan stays on even though the gauge doesn't suggest overheating. Your '84 CRX doesn't have OBD, but maybe something else would work?
In my case the coolant temp gauge in the dash stops at 90°C/194°F, even when my SGII was showing 114°C/237°F (broken fan in traffic jam during heat wave)!

Many ecomodders have their grille blocked only partially, and block off more during the colder months. Others have made their grille blocks openable. Here is mine:
http://ecomodder.com/forum/attachmen...1&d=1279801786

I use the dash gauge to check temp. I also check the water level. If it is not losing water, it is noty running too hot. the crx came stock with a partial grill block, so I may only need the full grill block in the winter. since I diligently
check mpg at every fillup, I will be able to determine if mileage goes up or down . I do know that my last tank, with the full upper grill block in place, was my worst tank , @ 50.54 mpg. lt is usually in the high 50's, so this was a significant drop.

your '84 is more mechanical than electrical, so making mechanical changes like a grill block will take more effort. if you do want to keep the grill block, i would invest in an aftermarket digital gauge and sensor, make sure the sensor is mounted on the coolant outlet side of the engine. for anybody else who runs across this with OBDII, as long as your car has an opening to pull air in when the fans come on, you're fine, just be aware of how hot you want your engine.

since removing the grill block, my mpg is back up to 58.98 mpg. I believe the fan staying on for so long with the engine shut off was draining the battery enough to cause the alternator to work harder. it is also possible that the under hood temps were just too high. whatever the reason, it looks like the grill block only works in colder weather for my crx.