pezs2007

Ok so I bought this ex about about 3-4 months ago, the day after I bought it it overheated so I bought a radiator and it fixed the problem. Till about 3 weeks ago, the car overheats on long drives and sometimes on 15 min drive if I have the AC on. But in the city its fine on short drives. This is what I've done to it all new parts! Radiator, radiator cap, radiator fan, fan temperature switch, cooling fan relay, cooling flush, water pump and timing belt,. I made sure all the markings matched when I did the belt. I go to a school called UTI where its a school for mechanics, and I had about 20-30 students and 1 teacher (all students were advanced students and have been there for well over a year) and everybody was scratching their head. I was told by my teacher that it could be my ECT (engine control temperature), my timingbecause I didn't do it with a timing gun, and a buddy of mine told me that it could be my computer. Oh I forgot to mention when the car overheats the fan DOES NOT turn on and I already replaced almost everything for the fan and I know the fan works I tested it. I also know that its not a cracked block or blown headgasket because I don't have cross contamination and I don't burn coolant. We also did a block test which said I did not have a cracked block. I am SO CONFUSED and in desperate need of help! Any suggestions?

04 Honda Civic

iTrader: (2)

Test or replace the thermostat.

Does your heat blow hot?

pezs2007

I put a new thermostat in
Yes the heater does blow hot

suaveflooder

When you say "long drives" are you talking about freeway driving? Or are we talking about prolonged stop and go traffic? On the freeway, your fan shouldn't be running anyway. When you checked that the fan, did you jump it or just flip the key to the accessory mode? You said it's not coming on when the car is overheating. Stupid question, but have you checked the fuse? I hope you can get it figured out.

pezs2007

I mean freeway driving for 15-20 min then when I get off the freeway it overheats. I checked the fan by jumping power trough the fan temperature sensor switch, I also got a 18 volt battery jumped it and it turned on. But yesterday when I was in my autoshop class I was trying to make it overheat by leaving it on and it wouldn't but the fan would work properly. Also when it overheated one time I manually started the fan and it didn't really seem to help. Oh and no its not the fuse.

suaveflooder

WOW! Crazy! It's probably working on the street for short drives because of the stop and go and the fan probably not ever turning off. When you're on the freeway, the fan turns off and it's supposed to kick back on when you slow down enough and aren't pulling enough air through the radiator (I'm thinking out loud, because I'm sure you know this working at UTI). For some reason the fan isn't being told to turn back on. That is really weird. With everything you've changed, I'm at a loss. It sounds/acts like a relay (fan temperature switch) with a bad switch. Could be the computer, but I don't see why that would all of a sudden go bad and your car would continue to run fine.