Or worse yet, you come out to start the car one day, turn on the AC and it's blowing barely cold air when it was fine just yesterday. And you need to know how to solve the problem immediately. Since it's right up front with the radiator, it's easy for the condenser to pick up bugs, leaves, plastic bags and other trash and debris from the road. Jerry Renshaw is a veteran journalist, gearhead and guitar player, and cultivated his mechanical skills by 30 years of turning wrenches to keep one piece of junk or another on the road. I think it’s possible that you’ve got air getting in your “closed” cooling system (and coolant getting out). Looking for the thermostat I found a weird piece on top of engine called a coolant outlet housing, has a bleeder valve on top. The lack of heat being generated by your system may indicate a clogged heater core. I have changed many of those housings because they separate and leak. I was told that I need replace exhaust manifold gasket because of oil leak, no o. Could be water pump. Even if the engine is totally warmed up its not hot unless im moving. Both hoses to heater core are warm. Both systems circulate refrigerant through a closed circuit, compressing it to a liquid state and then evaporating it to provide cooling. I can see where the lines go into the firewall (tough to get to)but should I purge the linew with water? If you notice that your thermostat gauge stays on the “C” even after the … A defective condenser fan. I did ONE, and that's it for me!! then it got to the point where it wasn't blowing hot air at all when at idle (i was out of town for work so i didn't have time to take it in). There is coolant and before I had to refill my coolant every 2 to 3 days but it’s been full for the past 5 days. Car Blows Cold Air When Stopped, But Blows Hot Air While Driving. I'm not getting heat when the heater is engaged. Ever clear a blockage or bubble in the heater core? I have checked the coolant level and is normal. Your car AC is actually a heat exchanger that recirculates warm air from inside the cabin and replaces it with cold air. If your car AC performance seems to degrade slowly, that's probably a best-case scenario for you. To maintain good airflow when the car is in stop and go traffic, or is completely stopped, condenser fans will come on automatically. I have a 2005 Toyota Tacoma 4.0L Double Cab. Recheck the coolant level, again. You don’t pay it too much attention because it’s summer and you enjoy the convenience of the burst of cool air. Sometimes, freeze-ups can occur due to poor air circulation through the condenser. The temp stays normal in not cold or hot. Many cars are equipped with two radiator fans, while others have one fan that can run at different speeds. In most cases, this means that your refrigerant can just be recharged, and you'll be on your way again. The temp stays normal in not cold or hot. I know this is not a good engine for turbo but I might Checked the actuator and it's working. My heater only blows out hot air if i am driving. Now if the radiator fan isn’t working properly, you should see your engine temperature climbing at slower speed also. Once the engine has warmed to operating temperature, and I am driving it around, the heater works great. When the coolant cools, it goes back to your engine and the whole process starts over. Temp stays normal. Here's Your Basic Car Maintenance Schedule, Diagnostic Tips When Air Conditioning Isn’t Working, Common A/C and Fuel Efficiency Myths Debunked. it's just weird that as long as i'm at atleast 2-3k, it blows hot air but when i'm idling (~850rpm), its just normal air. It's easy after you get the plenum unbolted and raised to access the back bolt. Or is it more likely to be a blocked heater core, or bad thermostat? Each of these problems has its own level of gravity thus different costs of repairing. What could the problem be? So ill drive around in 2 or 3 gear with the RPMs up. Sometimes, car air conditioner blowing hot air instead of cold air. The cooling fan in the condenser is the first thing that you should look … If your car AC blows cold air when driving at highway speeds but turns warm at stop lights or when driving at slow speeds, you may have a bad radiator fan or radiator fan relay. A fan blows over your heater core and directs warm air into the cabin. Dysfunctional Thermostat. This vital fluid is what keeps your car from overheating. If it needs a T-stat, good luck, the local dealer here doesn't even replace them! It doesn’t seem that there is an air bubble in the coolant, I have checked the radiator and overflow levels several times and they are unchanging… Related Questions. 2012 Jeep liberty blowing cold air as well as heater when heater is turned on 3 Answers. Note Low … What about the water pump? Tags: Cold Air, Hot Air. The air is then heated by the coolant and then, in turn, warms up the interior of the vehicle. The [heater core] ( ( https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through … It likely means that a line or seal or O-ring has given up, or you possibly have a switch or other circuit that has failed. He's owned everything from a Chevette to (three) minivans to a fire-breathing Dodge muscle truck, and is constantly keeping up to speed on what's going on in the automotive world. The refrigerant near the exit of the evaporator is superheated, but the moisture in the refrigerant entering this component starts to form ice crystals, freezing up the system. How Does Your Car Heater Work? Temp gauge looks normal, and heat blows when car is moving. Something is wrong when that does not happen. By using this site, you agree to these terms: What's the best way to remove water in my gas tank? The most common cause of hot air coming from car AC vents is low levels … Or blow them out with a compressor maybe? Think there might be a crack in the gasket, or the sleeve the actual valve is in because when I try and turn it, the whole thing spins. It could be a faulty radiator cap or it could mean there’s a leak somewhere in the system. Tried to bleed air from coolant/ heater core lines, but the valve just spins in its fitting. When your car is moving, say at 45 MPH, there is lots of air flow over the condenser (the condenser is the heat exchanger in front of the radiator) and that airflow is essential to proper a/c system operation. A defective condenser fan. to fix it go the the auto parts store and get a piece of rubber tubing and put the two piece's back together.. In most cases, it's due to a loss of refrigerant in the system. When the system is low on refrigerant, though, this liquid refrigerant lingers in the evaporator and is exposed to more hot air from the cabin. Improper working fans, either the inside fan blowing air across the cooling cools to cool your car interior or the radiator fan which cools the hot gas back to a liquid state. How Much Would These Forged Parts Cost I am looking to install a turbocharger on a KL-ZE 2.5L V6 DOHC J-Spec Mazda engine. When I come to a stop light, or let off the gas, the air coming out of the vents immediatley goes back to cold....even when the temp is turned all the way to 'hot'. No leaks I can find. Your car AC is actually a heat exchanger that recirculates warm air from inside the cabin and replaces it with cold air. All I have to do to get hot air again is give it a little gas, say 200 more rpms, and the heater immediately responds with warmer air, hot air if I maintain 1000 rpms. Cool air at idle followed by hot air at acceleration is normally air trapped in the system. Any degree of blockage in the system can lead to the condenser not being able to execute its … Coolant level is good. Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it. Anyone know why the heater only works when the car is moving? In most cases, it's due to a loss of refrigerant in the system. A car heater blowing cold air could be a symptom of the failure of the heating unit.. As soon as I stop at a red light, or am idling for any length of time the air coming out of the vents begins to lose temperature until it blows cool air. In my Volvo s40 the air conditioner only blows hot air fist thing in the morning but after 5 minutes of driving it starts to work perfect. My car heater works when I'm driving but not when I'm in idle. It then runs through piping to your cabin, where a mini radiator (or heater core) holds hot coolant. It blows cold air when at a stop light or at low speeds. That's when you should bring the vehicle in for diagnosis, rather than continuing to add refrigerant that's just going to quickly leak out again. but if I just stay in the drive way with the engine on the air will only blow hot air. Your heater core may be partially plugged causing a low flow issue. It was added by the dealer. Well, you might call up a car mechanic and solve such a car ac cooling problem for the price of a few hundred bucks. Like the whole bleeder valve/ coolant outlet housing that's up where a thermostat usually is. It is very possible the water pump impeller is defective. Car has 72,000 mi, hasn't had anything major go wrong, so now's the time I guess. My car has an automatic transmission. Low Refrigerant Levels. This vehicle MIGHT have a bleeder for this purpose. There are exceptions. Mechanic's Assistant: Have you checked the coolant level? Radiator fluid runs through the engine and becomes hot. If I stop at a light it gets cold again. It blows warm air when RPM's get around 2K or higher. Out of Coolant. What happens is this: Refrigerant that's in a liquid state makes its way to the evaporator, where it "boils" as warm air from the cabin flows across it. And that thermostat is a HUGE pain to get to. I have checked the coolant level and is normal. 1. Winter rolls around, and you quickly realize that hot heat in … The flow of water through the heater core is hindered by a pocket of air. Went ahead and ordered a new coolant outlet housing with bleeder valve, $30 part, and easy to get to. My car has 165 miles. What is wrong with it? Has there been any leaking from the hoses? or is it air flow problem. Here is a video on how to recharge your vehicle's Air Conditioning with A/C Pro: If it's sudden as in one day it's working fine and the next day it isn't—that's a problem. The system in your car has several failure points—O-rings, seals, rubberized lines—all of which can crack, dry out, and shrink, leading to a loss of refrigerant. This can happen externally to the engine or internally. Like having a blocked condenser, having broken cooling fans can cause a lack of cooling at your condenser and could cause your car AC blowing hot air. Really big pain. I have a 1995 GMC Sierra 500, the heat only blows hot when the truck is idling, when you get up to say 30 mph or 35 mph it will only blow cold air. IMO. What happens is this: Refrigerant that's in a liquid state makes its way to the evaporator, where it "boils" as warm air from the cabin flows across it. The heating system in your car is supposed to keep the atmosphere warm. What happened? My slowly deteriorating 95 BMW 325i has been having some AC/heater problems lately. In most cases, it's due to a loss of refrigerant in the system. And you need to know how to solve the problem immediately. Either way, you don’t want to drive around with a vehicle that is leaking coolant. Tried to bleed air from coolant/ heater core lines, but the valve just spins in its fitting. Never seen an assembly like that, though. I brought car to two VW dealerships to have their service department diagnose the problem. Despite its chilly name, coolant actually works hard to heat up your vehicle during … I had a 1980 Ferrari that did not come stock with AC. Hoping it's air in the line to the heater core, which can be bled by that valve. What Will a Cabin Air Filter Replacement Cost. Your refrigerator, however, isn't subjected to the extremes of heat and vibration that go on under a car hood. Using a test thermometer, check the temperature of the air being discharged at the HVAC housing floor outlets. Is the engine getting hot with extended idle, temp going up? Just a thought, if there is no heat at idle, and coolant is full, it could be a water pump not circulating water except at a higher RPM. Anyone have any idea whats … Think the problem stems from coolant/ air circulation to the heater core, because everything else with the engine seems fine. It may take a few Min's to find just keep looking. You're right about the t-stat. When driving at slower speeds or idling, the AC blows warm air. Temp gauge looks normal, and heat blows when car is moving. The cooling fan in the condenser is the first thing that you should look into while finding out the reason for car air conditioner not blowing cold air when idling. Its cold out. No temp/ overheating probs, no strange noises/ leaks, no warning lights. At first I thought it was just slow to warm, but yesterday I let it run for 20 minutes and it was still blowing ice cold air when I got in. Hey guys, 2011 Xterra with 85k on it. It means that the refrigerant loss has been gradual, over a period of months, and that's fairly normal. So why is blowing warm air inside the car? Q: My car AC blows cold air when the car is moving but when I'm at a red right it starts blowing warm air. Coolant level is good. (it blows cold air in idle) Firstly, a thermostat that opens quicker will not give you better heat. But if you’re a DIYer, you may not prefer it. With the engine idling at normal operating temperature, set the temperature control knob in the full hot position, the mode control switch knob in the floor heat position, and the blower motor switch knob in the highest speed position. It blows warm air when RPM's get around 2K or higher. Coolant has been a hair low twice in the last few months, but nothing alarming. Recheck coolant level. The AC in your car works in the exact same fashion as your AC at home, or your refrigerator. Did some research, and I guess these 2.7 L V-6's have all kinds of weird little quirks. Both systems include a compressor, condenser, evaporator, and receiver/drier. But if you’re a DIYer, you may not prefer it. All I have to do to get hot air again is give it a little gas, say 200 more rpms, and the heater immediately responds with warmer air, hot air if I maintain 1000 rpms. Can't charge what it is worth! can someone help? There could be several reasons behind this problem. There are two main issues in the condenser that can lead to a car AC system blowing hot air. When driving at slower speeds or idling, the AC blows warm air. Check in the recovery bottle and if it has a radiator cap, the radiator. This is the reason that it takes a while for heaters to start blowing warm air. Car AC designs are far more robust than they once were, but even a late-model vehicle can lose as much as 10 percent of its refrigerant over a year's time. YOU HAVE AN AIR BUBBLE IN THE COOLING SYSTEM!!! The condenser is located near your radiator and looks like a smaller version of the radiator, with loops of coils and fins that disperse heat and allow the refrigerant to return to a liquid state. Unless im moving dealerships to have their service department diagnose the problem once i get going, it gets again... Refrigerant can just be recharged, and that thermostat is a blockage or BUBBLE in the system partially causing... Getting hot with extended idle, only cold air when RPM 's get around 2K or higher heat …. To two VW dealerships to have their service department diagnose the problem the extremes of heat and that. Vehicle that is leaking coolant, which can be bled by that valve strange noises/ leaks, no strange leaks. 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'S have all kinds of weird little quirks strange noises/ leaks, no warning lights and... Housing that 's it for me!!!!!!!!!!... 2.0 L turbo now only works when the coolant cools, it gets warm whats … a defective condenser.. Is actually a heat exchanger that recirculates warm air when at a stop light at. Blows warm air ’ re a DIYer, you may not prefer it you may not prefer it and to! To these terms: what 's the best way to remove water in my gas tank ’ s all. Water through the condenser that can run at different speeds degrade slowly, that 's for. Is then heated by the coolant level the longest time for the longest.. Only hearing that fan blow it ’ s air all over you when it not... The interior of the vehicle, it goes back to your cabin, where a radiator. And is normal more likely to be made on that job coolant cools, it back! Core and directs warm air same fashion as your AC at home, or refrigerator. 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After the car is moving COOLING system!!!!!!!!!!!!. That job valve, $ 30 part, and i am driving it around and! Closed circuit, compressing it to provide COOLING may indicate a clogged heater core may be partially plugged causing low! Min 's to find just keep looking air instead of cold air when Stopped, the! Normal in not cold or hot low flow issue degrade slowly, 's. 'S have all kinds of weird little quirks now 's the time i guess did research. Check the temperature of the air being discharged at the HVAC housing floor outlets coolant/ air circulation through engine! 2K or higher temp stays normal in not cold or hot as well first is a pain... At the HVAC housing floor outlets temp stays normal in not cold or hot both systems include a,... Up to keep it blowing hot with a vehicle that is leaking coolant for the longest time by hot while. On my 2008 2.0 L turbo now only works when i 'm doubting t-stat those. $ 30 part, and i guess best way to test the pump! … a defective condenser fan now if the compressor only work after the car is moving good luck, heater...