Today while sitting in the drive through at In-N-Out for lunch, my car started blowing hot air and the temperature needle climbed past the 3/4 mark and the red light was on. I started freaking out but finally the fans kicked in and it cooled to about the halfway mark and cold air started flowing again.

But while sitting in traffic I would feel the rpms go from it normal idle at 600 to about 750 every ten seconds or so, so I'm guessing the fans where going on/off. Today it was about 102 so it was pretty hot, so I checked the coolant and everything was fine. Then when I got back to work and turned off the car, the fans where on at full speed for a good 5 minutes after the car was turned off. It had never done that before today. It did the same thing on my drive back home, I can actually hear the fans still on in the garage. Every time the car stopped moving, the ac would blow hot air, but as soon as it started moving cool air came out again.

It sucks that my 03 with 39k miles would have something like this go bad so soon, and I just replaced the rotors and brake pads, so this is definitely not a good time to put more money into it.

 

Carwatcher, open the hood and see how much air the fans are moving. The fans should be moving enough air to blow your hair around when they are going at full speed. You can get the fans to full speed at any engine temp by turning the A/C on in the manual mode with the fan on max and the temp dialed to the lowest temp. If your are not getting a lot of air, then odds are your fan module is giving you problems. If 1 fan is blowing and the other is not, then you have a bad fan.

If you need more info, let me know.

 

Yeah, I did that yesterday and both fans where on but hardly felt any air at all, they actually turned off for a few seconds and then came back on, but was not getting any air. I did the test this morning again with the engine cold and the fans were on but felt no air. I drove around a bit this morning and it didn't overheat, but it's probably because it's cool outside and I only drove about 5 miles....is it possible this was a one time thing? But just in case I found a used fan assembly on ebay for about $120, so I'll swap out the module and hopefully it'll be fixed.

 

Carwatcher, what you are describing is the classic signs of the fan module failing. It isn't a problem at highway speeds because the air moving through the grill is more than the fans could move. So, at speed you are good. It is when you are under about 30 mph that you will run into the lack of air flow (as you have found out). Put in a new fan module (or the whole fan assembly if you get it that way) and then see how things go.

If you do replace the fan module, could I get your old fan module? I will pay for shipping to get it to me. I am looking to come up with a way to have us do our own repairs instead of having to go through what you are doing. I just haven't been able to get my hands on a used module.

 

Yeah, I can send it...I should be getting the replacement on wednesday. I hope that the module is the cause of my problems because I haven't seen any overheating yesterday or today. Granted, I did not drive more than 10 miles and the only symptom I saw was the revs shifting up and down every 10 seconds or so when at idle. I'll drive a bit more tomorrow and see if the temp goes up.

 

carwatcher, as long as you are maintaining highway speeds, it probably will not overheat. It is when you go to sitting in stop and go traffic that you are going to have issues. As long as you can keep the speeds over 30 mph (ish), you will not have any cooling issues.

 

Well, all of my driving was on city streets...I did that test again where you put the fans at top speed and at the coldest temps while the engine is cold and after 5-10 seconds I got a full blast of cold air through the vents, so I go out and opened the hood but couldn't feel any air coming from the fans. The fans where on, just not at full speed. So if the module is malfunctioning is it still possible to get a full blast of air through the vents inside the car even if the cooling fans are on but not at full speed?

 

Ok, this is weird. I just went out for long city drive and the car drove like nothing was wrong at all. The outside temp was 90 degrees, the fans where functioning like normal, they didn't turn on/off every ten seconds like it used to. I pulled into a gas station and just parked there with the engine on for about 20 minutes and nothing happened, the temp gauge sat just below mid point like it always used to do. I even opened the hood with the ac up all the way and felt lots of air coming from the fans, the rpm's didn't go up and down like it used and just no symptoms at all.

 

carwatcher, for the first minute or so, yes, you will get cold air from the A/C. But, if you let it set for a little bit, you will find that the A/C will star to get warmer and warmer.

 

Yes, it did that for a few days. But as of yesterday and today, the ac has been pretty constant. Today I drove for quite a bit in traffic and never got any hot air out of the ac and never overheated as it did last week.

On Sunday I was checking the connections of the module to see how hard it would be to change and reach them, maybe something was loose and when I moved them to check they went back into place? Is this possible?

 

Carwatcher, yes, this is possible. Keep an eye on things and see how it does. The outside temp can have a little bit of an effect on how the car operates too. If it has been cooler than normal, then it can cause what you are seeing too. BUt, it sounds like the plug was just loose.

 

i had a bad fan module and honestly i don't know when it failed on me. i just know when summer came my temp gauge was rising everytime i was in traffic and the ac was blowing warm air. when ever i was on the free way, everything was normal.i replaced the module and everything was normal.
Thermo i have a bad fan module, inbox me your add i will send it to you through usps.

 

Did you had any problem changing the module? Is it easier to remove just the module by lifting the car and going underneath? I tried to reach the passenger fan connection and my hand just can't fit.

I just got back from a drive and it started overheating and blowing hot air in traffic, even though it was just fine yesterday. When I got home I opened the hood and both fans where off even though the temp gauge was almost at the the 3/4 mark(I quickly turned off the car after checking), there was just a clicking sound every 10 seconds or so. And right before I started driving, when the engine was still cold, only the passenger fan was on.

 

I don't think you can reach anything from the bottom. I did mine from the top and it is real tight. I got a few scraped knuckles and some scrapes on my wrist and fore arm, my hands are not really small but if your hands are bigger than mine you might not be able to do it. I really had to force my hand and arm into the space to reach the passenger side fan connection.

 

How many bolts keep the module in place? I could only see one on top.

 

there is one bolt, i changed my module from the top, took me 3 hours mainly because i have big arms, so squizing through was an issue. i removed the battery and the stand.

 

Today I received the used module I bought from ebay, so I installed it...took me about an hour and when I went to test it, same old thing. I did the test, I felt some air coming but only from the passenger side, the driver's side fan was off but after a minute the passenger fan turned off too. So I went from a drive, and 10 minutes in it started overheating and blowing hot air in traffic. The ac would be cold and the the temp gauge would go back to normal once I started moving. When I got home, I opened the hood and the fans were off even though the temp gauge was way past the mid point.

So, did I get a bad module or is my problem something else? The module I got did look in pretty rough condition, but all the connections were good. I'm pretty sure I installed everything correctly.

 

I would say that it looks like you got took and bought a bad module.

 

carwatcher, how are you with a multimeter? I can give you a few wires to check and we can see exactly what is going on here. It may be possible you have a bad fan assembly, not a bad fan module (would be one of the first, but not impossible).

I will help you however I can to get you back to 100%. If you are not comfortable with a multimeter, just say so. I have other ways that require a little bit of wire construction, but it is all really easy stuff.

 

Well, I bought it from tom's foreign auto parts on ebay and they have a return policy. I just got an RMA #, so at least I'll get my money back.