I was up at Ford (which is right off the highway) the other day chatting with a buddy. It was about 85* out. I let the car sit at idle for maybe 10 minutes with the A/C on and when I got in to leave the car was in limp mode. I didn't realize it until I was getting on the highway then I saw that it was hot. The gauge showed 228* when I finally got the gauge switched to ECT. I turned off the A/C and was about to pull over and shut the car off but the temps started dropping instantly. They got down to 195* while on the highway so I went to a friend's house. Temps were still in the low 190's so I turned on the A/C and it didn't seem like the fans came on. I plugged in the Xcal3 to see when the tuner had them coming on. Low speed-176, high speed- 186. I changed them to 172/182 to see if they would come on and still nothing. While downloading the tune the high speed fan seemed to be working. I just got the car back a week ago from having the turbos installed. I have a Reische 170* thermostat, LFP radiator, and a PFAB overflow tank. I've been on here for the past couple hours trying to see if anybody has had similar issues but it most seem to be thermostat or not burped correctly.
Seems like the fans are not working
- Thread starter firedog90
- Start date
If there is enough air in the system, not only will it overheat, but the temp sensor may not get a reading and tell the PCM it's time to turn on the fan.
If you know the fan is still good and it functions when you turn the A/C on every time, do the burp fill procedure and see if there is air in the crossover tube fill location.
If you know the fan is still good and it functions when you turn the A/C on every time, do the burp fill procedure and see if there is air in the crossover tube fill location.
I'll try to burp the system to make sure it's good to go. With the A/C on fans didn't come on though.
Should the fan constantly stay on while the A/C is operating?
My fan cycles on/off periodically with the A/C on, but unlike the OP, the car does not begin to overheat. The car does constantly -like every couple minutes or so- make a loud sound similar to a blow off valve releasing pressure, when the A/C is running. The Ford tech said it's normal as the A/C is releasing built up pressure. Is this common? I admit it sounds kinda cool, but I've always wondered if the A/C system is not operating properly/efficiently and the loud blow off sound is due to some secondary problem within the A/C system as it doesn't occur with the heat on. I've never heard such a sound on any other car with the A/C on. The A/C does blow very cold though. The only other symptom I've noticed is that when I'm in stop-and-go traffic in the summer here in Arizona (110+ degrees outside), the A/C compressor intermittently turns off -stops spinning- for a while and won't turn back on for at least a few minutes or much longer. When I told the Ford tech about that last summer, he drove the car for 30 miles in stop-and-go traffic in the middle of summer, but of course the A/C never stopped for him...blew cold air the whole time. The only thing he said it could be was the fan turning off -he checked the A/C system for any problems; nothing found- which is why I wondering if the fans should always stay on when the A/C is running. Finally, I just want to add that when it is not a very hot day -like 80-90 degrees- the A/C runs fine, never stops blowing cold, but the fans still do cycle on and off periodically....this is why I'm confused about the fans constantly running when the A/C is on or not.
FYI, I installed a brand new Ford A/C compressor, orifice tube, and accumulator about 25K miles ago. I also had the radiator drained, flushed, refilled, burped, and installed the Reische 170 T-stat about 10K miles ago with the fans set to Reische's recommendations. The car never gets close to overheating. Also, the issues with the A/C I mentioned above were occurring a year prior to the radiator flush. Any ideas?
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What about when loading a tune? The high speed fan kicks on then but not when the car is running or A/C. I thought maybe there was some sort of relay or sensor that may have gone bad instead of the fan.
Just this past weekend, Goss' Garage on Motorweek TV discussed A/C diagnostics. One of things he mentioned to check when it comes to fan issues was the relay/sensor that plugs into the fan...someone above mentioned something similar about checking the wires going into the fan plug...I assume that's the same thing. I don't know the exact location of the relay/wires mentioned, but it may be a good place to start to see if they're corroded before buying a new fan. Maybe someone here can tell us where the relay/fan plug is located...
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The electric cooling fan on the rad does not cycle off when the a/c is on.
If it does something is wrong because it is intermittently shutting off on it's own.
Relay, wiring... what ever, it should come on and stay on anytime the A/C is turned on.
If it does something is wrong because it is intermittently shutting off on it's own.
Relay, wiring... what ever, it should come on and stay on anytime the A/C is turned on.
A burned out fan seems to be a right of passage for these cars. Check the fuses (underhood) too. It's happened to a lot of us.
Got it...Thanks! :burnout:
Don't worry these fans are available for cheap at Rock Auto.
So, would we need to order the Radiator Fan Assembly or the Radiator Fan Motor? Thanks.
My fan wasnt turning on either recently. Turned out to be the fan resistor, might want to give it a check first. It was only $30ish from Tously.
Where about is the resistor located and how do I know if it's bad or not? My fan intermittently cycles on/off when running the A/C, rather than constantly staying on as others' have mentioned it should do.
Location: If you are standing in front of your car looking down at the fan, it is in the middle left side of your radiator attached to all the fan plastic stuff. Its a piece that has a wire running to it and it clips into the fan. The clip part is greyish in color and when you pop it off the resister is silver with green stuff (whatever you call it) wrapped around it.
I knew it was bad because it was visibly broken apart.
I know my location description sucks so let me see if I can find a picture of what im talking about.
If the fan doesn't run ever, you need the whole fan assembly. If the resistor goes out you will only lose the low speed typically.
My fan tends to cycle on and off when running the A/C...what do you think it could be? On really hot days here, like 105+ degrees, the A/C compressor will stop spinning altogether. Last summer the Ford tech said the only thing possibly causing the compressor to stop would be if the fans stop running when the A/C is on, but at that time he could not get the damn A/C to stop even when driving it in stop-and-go traffic for 30 miles. Anyway, I've just started using the A/C the past few days....blows cold, doesn't stop blowing cold, BUT the fans do still cycle on and off frequently! hahaha what do you think? Could the cycling be from a mistake when setting the fans when the car was tuned?
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When the A/C is on the low fan speed should run constantly. Likely what you're seeing is the high speed cycling on and off due to coolant temps which has nothing to do with the A/C being on. I'd say check your fan resistor.
I just had the same issue, fan kept blowing the big 50 A fuse under the hood, went with a Mishimoto fan from American Muscle, great fan does an excellent job and doesnt sound like a jet. 70 something bucks? Then went through the burping procedure for a week! Its finally acting right.
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