ECM/Fan Problem

[Tom_O]

Hi,

I am having work done on my 90 Reatta. I found it was over heating (had a flush & fill and fluid change). At 70+ on the freeway no problem. In town the cooling dosen't recover enough and it overheats progressivly. My mechanic checked the trouble codes and he said that the two speed fan is not operating correctly. He suggested wiring it to be one speed (high) instead of two. He is going to temp wire it and drive it during the heat of the day (Texas, 99 yesterday) and get back to me.

My question is will this screw up the ECM? He's doing this so he dosen't have to take the ECM out and disassemble the console and charge me excessive labor. Your thoughts? <img src="http://forums.aaca.org/images/graemlins/confused.gif" alt="" />

[Guest F14CRAZY]

Um, is your thermostat fairly new? The stock system should be able to cool the engine sufficiently. I'm thinking your thermostat isn't opening properly. Cheap and not bad to replace. Retrofit it with a 180 degree one.

[Reatta45]

This heat is different, Texas heat like Kansas heat is harder to move? In slow moving/stopped traffic it still will get hot. <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" /> <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" />

The high speed relay gets energized from 2 different paths, the engine temp sensor and the high side switch on the A/C, since these do not cause any interference with each other I would think you could add a third energizing path from a switch to that relay to select high whenever you wanted it? KennyV.