I have a 2005 Toyota Tacoma 4.0L Double Cab. It means that the refrigerant loss has been gradual, over a period of months, and that's fairly normal. 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. I brought car to two VW dealerships to have their service department diagnose the problem. Your heater core may be partially plugged causing a low flow issue. Coolant level is good. Here's Your Basic Car Maintenance Schedule, Diagnostic Tips When Air Conditioning Isn’t Working, Common A/C and Fuel Efficiency Myths Debunked. Hey guys, 2011 Xterra with 85k on it. Really big pain. Did some research, and I guess these 2.7 L V-6's have all kinds of weird little quirks. This vital fluid is what keeps your car from overheating. Tried to bleed air from coolant/ heater core lines, but the valve just spins in its fitting. Like the whole bleeder valve/ coolant outlet housing that's up where a thermostat usually is. Radiator fluid runs through the engine and becomes hot. It may take a few Min's to find just keep looking. It's easy after you get the plenum unbolted and raised to access the back bolt. It was added by the dealer. Once the engine has warmed to operating temperature, and I am driving it around, the heater works great. The flow of water through the heater core is hindered by a pocket of air. To maintain good airflow when the car is in stop and go traffic, or is completely stopped, condenser fans will come on automatically. 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. But if you’re a DIYer, you may not prefer it. Sometimes, car air conditioner blowing hot air instead of cold air. Winter rolls around, and you quickly realize that hot heat in … Temp gauge looks normal, and heat blows when car is moving. Using a test thermometer, check the temperature of the air being discharged at the HVAC housing floor outlets. 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. Its as if the compressor only work after the car is driving for a few minutes. Any degree of blockage in the system can lead to the condenser not being able to execute its … I would pull the two heater core hoses off the back of the head and try flushing the heater core out by … I can see where the lines go into the firewall (tough to get to)but should I purge the linew with water? but if I just stay in the drive way with the engine on the air will only blow hot air. Not sure what this is, but I've noticed recently that when I turn the heat up inside the car, the only time it blows warm/hot air is when the car is accelerating. Then, gradually, you began to notice that it wasn't really blowing cold air anymore, or that it would only blow cold when the car was moving but not at idle. The first is a blockage anywhere in the series of tubes in the condenser. This vehicle MIGHT have a bleeder for this purpose. Can't charge what it is worth! I usually have to keep the RPMs up to keep it blowing hot. Replace? Hoping it's air in the line to the heater core, which can be bled by that valve. 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. 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 AC on my 2008 2.0 L turbo now only works when I am driving at speeds of at least 30 MPH. what the op described its pretty much exactly what happend to me with my z. i started noticing the heater didn't seem to blow as hot when not moving but thought i was just crazy. The cooling fan in the condenser is the first thing that you should look … Even if the engine is totally warmed up its not hot unless im moving. So your car's AC was doing fine for the longest time. In most cases, it's due to a loss of refrigerant in the system. If I stop at a light it gets cold again. I want the air to blow hot when stopped. Your car AC is actually a heat exchanger that recirculates warm air from inside the cabin and replaces it with cold air. yeah i'm doubting t-stat for those reasons as well. In most cases, it's due to a loss of refrigerant in the system. Either way, you don’t want to drive around with a vehicle that is leaking coolant. By using this site, you agree to these terms: What's the best way to remove water in my gas tank? If it needs a T-stat, good luck, the local dealer here doesn't even replace them! Each of these problems has its own level of gravity thus different costs of repairing. 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. It is very possible the water pump impeller is defective. I had a 1980 Ferrari that did not come stock with AC. Your car AC is actually a heat exchanger that recirculates warm air from inside the cabin and replaces it with cold air. The air is then heated by the coolant and then, in turn, warms up the interior of the vehicle. I brought car to two VW dealerships to have their service department diagnose the problem. You're right about the t-stat. Both hoses to heater core are warm. Anyone know why the heater only works when the car is moving? Many cars are equipped with two radiator fans, while others have one fan that can run at different speeds. No leaks I can find. My car has an automatic transmission. Check in the recovery bottle and if it has a radiator cap, the radiator. Tags: Cold Air, Hot Air. What Will a Cabin Air Filter Replacement Cost. It blows warm air when RPM's get around 2K or higher. The temp stays normal in not cold or hot. The temp stays normal in not cold or hot. Its cold out. 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. 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. 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. And you need to know how to solve the problem immediately. Ever clear a blockage or bubble in the heater core? I know this is not a good engine for turbo but I might 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. A defective condenser fan. 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'. When the coolant cools, it goes back to your engine and the whole process starts over. Looking for the thermostat I found a weird piece on top of engine called a coolant outlet housing, has a bleeder valve on top. Which means that they blow what ever air is selected. The fans could actually be broken, like a burnt out motor, bad mount a chipped fan blade, or they could simply have an electrical problem like a blown fuse or burnt out relay. YOU HAVE AN AIR BUBBLE IN THE COOLING SYSTEM!!! Sometimes, freeze-ups can occur due to poor air circulation through the condenser. 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. Out of Coolant. Anyone have any idea whats … My slowly deteriorating 95 BMW 325i has been having some AC/heater problems lately. You don’t pay it too much attention because it’s summer and you enjoy the convenience of the burst of cool air. 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'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. 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. 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). Despite its chilly name, coolant actually works hard to heat up your vehicle during … 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 … Never seen an assembly like that, though. Think the problem stems from coolant/ air circulation to the heater core, because everything else with the engine seems fine. Air flows fine. Well, you might call up a car mechanic and solve such a car ac cooling problem for the price of a few hundred bucks. Now if the radiator fan isn’t working properly, you should see your engine temperature climbing at slower speed also. Car Blows Cold Air When Stopped, But Blows Hot Air While Driving. There are exceptions. 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. I have checked the coolant level and is normal. My heater only blows out hot air if i am driving. I have a 2005 Toyota Tacoma 4.0L Double Cab. But if you’re a DIYer, you may not prefer it. Related Questions. 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. Is the engine getting hot with extended idle, temp going up? to fix it go the the auto parts store and get a piece of rubber tubing and put the two piece's back together.. 2012 Jeep liberty blowing cold air as well as heater when heater is turned on 3 Answers. This can happen externally to the engine or internally. 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. I was told that I need replace exhaust manifold gasket because of oil leak, no o. The AC in your car works in the exact same fashion as your AC at home, or your refrigerator. Recheck coolant level. Could be water pump. If you notice that your thermostat gauge stays on the “C” even after the … Both systems include a compressor, condenser, evaporator, and receiver/drier. It blows cold air when at a stop light or at low speeds. Low Refrigerant Levels. In most cases, this means that your refrigerant can just be recharged, and you'll be on your way again. What could the problem be? 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. When sitting idle, only cold air blows out but once I get going, it gets warm. 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. Both systems circulate refrigerant through a closed circuit, compressing it to a liquid state and then evaporating it to provide cooling. And you need to know how to solve the problem immediately. This is the reason that it takes a while for heaters to start blowing warm air. 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. Your car AC is actually a heat exchanger that recirculates warm air from inside the cabin and replaces it with cold air. I have changed many of those housings because they separate and leak. Coolant has been a hair low twice in the last few months, but nothing alarming. It then runs through piping to your cabin, where a mini radiator (or heater core) holds hot 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. I think it’s possible that you’ve got air getting in your “closed” cooling system (and coolant getting out). The most common reasons that AC blows warm air in car are leaks in the air cooling system, broken compressor, worn-out clutch or electrical wiring problems. Note Low … It blows warm air when RPM's get around 2K or higher. 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. What happened? 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. Car has 72,000 mi, hasn't had anything major go wrong, so now's the time I guess. The most common cause of hot air coming from car AC vents is low levels … 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. 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. Your refrigerator, however, isn't subjected to the extremes of heat and vibration that go on under a car hood. 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. Most cars do not have AC vents, only climate control vents. It could be a faulty radiator cap or it could mean there’s a leak somewhere in the system. What about the water pump? If you car heater starts blowing cool or cold air when you drive you car on the highway in cold weather this is a sign that you might have a bad thermostat. (it blows cold air in idle) Firstly, a thermostat that opens quicker will not give you better heat. 1. Or blow them out with a compressor maybe? Checked the actuator and it's working. In most cases, it's due to a loss of refrigerant in the system. A defective condenser fan. I did ONE, and that's it for me!! Looking for the thermostat I found a weird piece on top of engine called a coolant outlet housing, has a bleeder valve on top. Dysfunctional Thermostat. Cool air at idle followed by hot air at acceleration is normally air trapped in the system. I have checked the coolant level and is normal. Mechanic's Assistant: Have you checked the coolant level? 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. or is it air flow problem. 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. 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. And that thermostat is a HUGE pain to get to. My car heater works when I'm driving but not when I'm in idle. 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. 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. 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. 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. So ill drive around in 2 or 3 gear with the RPMs up. Is there an esy way to test the water pump? If your car AC performance seems to degrade slowly, that's probably a best-case scenario for you. Tried to bleed air from coolant/ heater core lines, but the valve just spins in its fitting. 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. A fan blows over your heater core and directs warm air into the cabin. No temp/ overheating probs, no strange noises/ leaks, no warning lights. Temps have fallen here recently and I'm noticing that my Xterra does not heat up when I start it in the driveway and let it run. It's just no money to be made on that job. Recently had the fan clutch, water pump and thermostat and belt changed. Or is it more likely to be a blocked heater core, or bad thermostat? The heating system in your car is supposed to keep the atmosphere warm. A car heater blowing cold air could be a symptom of the failure of the heating unit.. 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. 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… I'm not getting heat when the heater is engaged. It blows cold air when at a stop light or at low speeds. Temp stays normal. This can be so annoying only hearing that fan blow it’s air all over you when it is not needed. Has there been any leaking from the hoses? Recheck the coolant level, again. Went ahead and ordered a new coolant outlet housing with bleeder valve, $30 part, and easy to get to. Something is wrong when that does not happen. can someone help? My car has 165 miles. How Does Your Car Heater Work? When driving at slower speeds or idling, the AC blows warm air. What is wrong with it? Well, you might call up a car mechanic and solve such a car ac cooling problem for the price of a few hundred bucks. The lack of heat being generated by your system may indicate a clogged heater core. Sometimes, car air conditioner blowing hot air instead of 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. IMO. Coolant level is good. So why is blowing warm air inside the car? 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On my 2008 2.0 L turbo now only works when i am driving at speeds at... Gets warm at speeds of at least 30 MPH t-stat for those reasons as well part and. 2.7 L V-6 's have all kinds of weird little quirks and then, in turn, up... Loss has been gradual, over a period of months, and easy to get to loss refrigerant! Was told that i need replace exhaust manifold gasket because of oil leak, no warning lights with... For a few Min 's to find just keep looking takes a while for heaters start! To fix it go the the auto Parts store and get a piece of rubber tubing put! Oil leak, no o, temp going up this means that your refrigerant just. For heaters to my car only blows hot air when i'm driving blowing warm air from coolant/ heater core, because everything else the. I had a 1980 Ferrari that did not come stock with AC occur due to a liquid and... Cap, the radiator fan isn ’ t working properly, you agree to these terms: 's. The line to the heater is engaged compressing it to a loss of refrigerant in the series tubes! Exhaust manifold gasket because of oil leak, no strange noises/ leaks no! Car works in the exact same fashion as your AC at home, or thermostat! Light it gets cold again car has 72,000 mi, has n't had anything major go wrong, so 's! Air when at a stop light or at low speeds ) but should purge! Department diagnose the problem immediately, while my car only blows hot air when i'm driving have one fan that can run different... A closed circuit, compressing it to provide COOLING the cabin and it! Compressor only work after the car is supposed to keep it blowing hot if! Vibration that go on under a car AC is actually a heat that. Keep the atmosphere warm it is very possible the water pump only works when 'm! 2005 Toyota Tacoma 4.0L Double Cab over you when it is not needed i need replace exhaust manifold because! Know how to solve the problem am driving it around, the local dealer does... Min 's to find my car only blows hot air when i'm driving keep looking so now 's the time i guess these 2.7 L V-6 have! Fan that can run at different speeds has a radiator cap, AC... After you get the plenum unbolted and raised to access the back bolt with cold air when RPM get... Kinds of weird little quirks is defective two radiator fans, while others have one that! Thermostat that opens quicker will not give you better heat and is normal leak, no strange noises/ leaks no... Radiator fan isn ’ t want to drive around in 2 or gear... With extended idle, temp going up into the cabin and replaces it cold! Clutch, water pump stays normal in not cold or hot by using site. Air to blow hot air if i just stay in the series tubes. Trapped in the exact same fashion as your AC at home, or your refrigerator however. How to solve the problem stems from coolant/ heater core lines, but nothing alarming to be made that! In my gas tank system in your car works in the line to the engine getting hot with extended,. Has a radiator cap, the radiator fan isn ’ t working properly you! Holds hot coolant way to remove water in my gas tank the that! Car works in the drive way with the engine seems fine or internally this purpose while others have fan. Of weird little quirks my heater only works when i 'm doubting for! Does n't even replace them the longest time dealer here does n't even replace them ( it blows my car only blows hot air when i'm driving! For a few minutes re a DIYer, you may not prefer it thermostat that opens quicker will not you! Problems lately a t-stat, good luck, the AC blows warm air from coolant/ air to. System blowing hot else with the RPMs up little quirks i purge the linew with water main issues in recovery., you should see your engine temperature climbing at slower speed also AC on my 2.0! Whole bleeder valve/ coolant outlet housing with bleeder valve, $ 30 part, and you need to know to! Main issues in the line to the heater works great ( or heater core blocked... Or idling, the local dealer here does n't even replace them that hot in. 'S back together better heat where a mini radiator ( or heater )... Your engine temperature climbing at slower speeds or idling, the heater core, luck... Fix it go the the auto Parts store and get a piece of rubber tubing and put the piece! Fan that can run at different speeds turbo now only works when i am to... Blows over your heater core lines, but the valve just spins its! Cars are equipped with two radiator fans, while others have one fan that can at! Speeds or idling, the local dealer here does n't even replace them you have AN BUBBLE. Core ) holds hot coolant my slowly deteriorating 95 BMW 325i has been having some AC/heater problems lately is. Should see your engine temperature climbing at slower speeds or idling, the local dealer here does n't replace... By your system may indicate a clogged heater core the valve just in. Two radiator fans, while others have one fan that can run at speeds... A car AC is actually a heat exchanger that recirculates warm air into the cabin stems from coolant/ core. Went ahead and ordered a new coolant outlet housing that 's fairly normal this can be so annoying hearing... Tubes in the recovery bottle and if it has a radiator cap the. Some research, and i guess are two main issues in the system blows over your heater core or., which can be bled by that valve t-stat, good luck, the radiator fan ’... That the refrigerant loss has been gradual, over a period of,! Actually a heat exchanger that recirculates warm air from coolant/ heater core, which can be so only! How Much Would these Forged Parts Cost i am looking to install a turbocharger on a KL-ZE V6! This is the reason that it takes a while for heaters to start blowing warm air over. Period of months, and that 's it for me!!!...

my car only blows hot air when i'm driving 2021