93 Accord Overheating Problem
str8killa
04-03-2007, 02:42 AM
I own a 93 accord with high miles, i have had the car for years and have a cooling problem. my fan has stopped working, i replaced all the sensors and the relay and still the fan wont work. that isnt the only problem. my car overheats at cruising speed (40mph). i connected the fan to the battery to see if the motor still worked and it does. the i made a toggle switch to run the fan to see if that was the problem which it wasn't. water pump has 25k on it, six month old radiator ALL NEW HOSES with no leaks. new thermostat. i dont think it is the head gasket because i dont smell or see coolant in the oil. any suggestions on either problem will be greatly appreciated.
jeffcoslacker
04-03-2007, 08:53 AM
Dumb question, but I have to ask... I've seen people wire the fans straight to power and get the polarity reversed, so the fans blow forward instead of inward...makes the car overheat at about the speed you describe....it's not that, right?
Next...check for abnormal pressure build-up. With the motor stone ovenight cold, start it up and let it run while feeling the upper radiator hose. If you feel pressure building long before you feel heat beginning to circulate, the head or head gasket is suspect.
Once it's warmed up, run it up to about 3000 rpm and watch the coolant tank. If it starts blowing bubbles incessantly after the initial expansion gets kicked over, again it could be a head problem.
You won't always see coolant/oil mixing with head problems. In fact, it's probably less than half the time. A compression to cooling jacket exchange is all that's needed to screw things up. If you've been running too hot for a long time, it's very possible.
If you decide this is the problem, make sure you find the source...many people put a new head gasket on without finding the leak, only to discover the head was cracked and the gasket job was pointless...
Do you loose any coolant, if so how much and how fast?
Next...check for abnormal pressure build-up. With the motor stone ovenight cold, start it up and let it run while feeling the upper radiator hose. If you feel pressure building long before you feel heat beginning to circulate, the head or head gasket is suspect.
Once it's warmed up, run it up to about 3000 rpm and watch the coolant tank. If it starts blowing bubbles incessantly after the initial expansion gets kicked over, again it could be a head problem.
You won't always see coolant/oil mixing with head problems. In fact, it's probably less than half the time. A compression to cooling jacket exchange is all that's needed to screw things up. If you've been running too hot for a long time, it's very possible.
If you decide this is the problem, make sure you find the source...many people put a new head gasket on without finding the leak, only to discover the head was cracked and the gasket job was pointless...
Do you loose any coolant, if so how much and how fast?
str8killa
04-04-2007, 05:31 AM
i fixed the overheating problem, it was the head gasket. i took your advice and noticed pressure was building up quick and it wasnt even warm yet i still have the problem with my fan not working. i wired the fan right, my buddy brought that up and i checked. now my car only starts to run warmer than normal when it sits for a while so i need to fix the fan. do you know where the fan timer is? i took my multimeter out and there is no power originally going to it. i already replaced the fan switch, the relay and the other two sensors. i cant see where the hot wire comes from for the fan. i ran my own hot line, ground and toggle for a temp fix. thanks for your previous input in fixing the problem.
jeffcoslacker
04-04-2007, 07:39 AM
I wish I could tell you...I really don't know but someone here will.
My friend's '89 had all kinds of fan problems I finally sorted out, but it had major wiring issues...most of which seemed to have been caused by dry, brittle wiring insulation that was beginning to split and get crossed up...what a mess.
Check your wiring back to the PCM, and if you can get a printout of the different voltages for the PCM terminals, you could see if A.) it's getting a temp signal from the harness, and B.) it's signalling the fan relay(s) to turn on, and the signal's not getting there...you know there's two temp sensors usually, right? One for the guage and one for the PCM? Sounds like you probably already replaced both...
Both fans should run when the A/C is on, how about that? Nothing then either?
My friend's '89 had all kinds of fan problems I finally sorted out, but it had major wiring issues...most of which seemed to have been caused by dry, brittle wiring insulation that was beginning to split and get crossed up...what a mess.
Check your wiring back to the PCM, and if you can get a printout of the different voltages for the PCM terminals, you could see if A.) it's getting a temp signal from the harness, and B.) it's signalling the fan relay(s) to turn on, and the signal's not getting there...you know there's two temp sensors usually, right? One for the guage and one for the PCM? Sounds like you probably already replaced both...
Both fans should run when the A/C is on, how about that? Nothing then either?
tubais
05-08-2010, 10:45 PM
fan timer is next to the master relay black box 1 nut 1 bolt 8 wire connector
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