ac only works when driving fast

The air conditioning compressor will turn off at the slightest rise of heat due to excessive HEAD PRESSURE - however the engine will not show any signs of overheating. This is the most common failure mode.

Ac Only Works When Driving What S Causing It

I popped the hood and noticed that when the AC compressor kicks on that it almost stalls the engine.

. Never saw over 900rpms on the fan. If i am revving the engine from 1000 to 2000 and back or accelerating the heater starts working. 2005 Dodge Ram 1500 SLT Big Horn 58L V8 Hemi my air conditioning only works when Im driving forward and does not work at all any more when Im sitting still at an idle.

The cooling fan in the condenser is the first thing that you should look into while finding out the reasons for car air conditioner not blowing cold air when idling. Separate names with a comma. One is that your condenser fan s is either not working or is worn out to the point that it cant spin sufficiently fast to bring enough air through the condenser.

There can be two possible reasons why your AC is only blowing cold air at high speeds. In other designs the failure of 1 resistor means you lose only one speed. So more power applied to the engine means more power applied to.

This could mean that there is some slipping on the belt and when you accelerate it activates something called a tensioner which helps keep the belt taut thus making the car blow cold air. Get a thermometer that goes in your vent to see if its hot as you think it is or not from Amazon HERE. And noticed that the second fan on the radiator never came on although i.

99 for a fan clutch. Up to 8 cash back The high pressure hose is designed to increase and decrease AC pressure during different driving conditions since the AC drive belt will increase in speed as the vehicle accelerates. However most car makers bypass the blower motor resistor completely when you move the fan speed switch to high.

This is a new problem. The AC on my 2008 20 L turbo now only works when I am driving at speeds of at least 30 MPH. As soon as you slow down the ac goes out.

The AC blows hard all the time but when you are sitting at idle at a redlight or something it goes from cold to lukewarm. It sounds like the air compressor or condenser are on the same belt as the main pulley. AC Blows Cold Air Only When Driving 30 MPH or Faster.

Basically the AC high pressure hose is kind of like a turbo for your AC - it supplies more pressure when youre idling and less pressure when the AC motor is. Feel like I was robbed to some degree. I checked the water pump.

The AC has worked like a champ for the past year since I started using this vehicle. To maintain good airflow when the car is in stop and go traffic or is completely stopped condenser fans will come on automatically. Driving with ac fan speed would hardly change just hold in the upper range of 380-500 sometimes higher.

Tuesday July 1st 2014 AT 742 AM. You need to take it to an AC shop so they can check and see if the expansion valve is working properly. Search this thread only.

At idle with ac fan speed is anywhere from 380-500rpm usually on the lower end. If the fan is damaged or cannot run with its full force it cannot cool down the heat coming from the Freon refrigerant through the condenser. A Faulty condenser fan.

So 17500 later the shop says it was the fan clutch. Up to 25 cash back Ac on auto only works when you drive fast. It is easy enough to check to see if the fans are working or not.

When it is at idle I. Pushrod on July 05 2019. Hi guys i am having a problem with WJ jeep 1999 47.

99 of the time this problem is caused by insufficient air flow into the engine bay while vehicle is in slow moving traffic or at stop with engine and a. Plus tax and some other 3 BS. You may have experienced this in other.

If this valve fails to go the proper position for refrigerant line temperature it doesnt convert the refrigerant into a gas but instead it remains a liquid and the cooling effect stops. When driving heating works-ish. It may come back but only when you -.

I even refilled it by myself last summer with no issues until now. Normally car AC systems are built so that the higher the engine speed RPM the faster the AC compressor turns. Search this forum only.

I am no expert in more recent vehicles but if the ac works only at higher driving speeds it could be because the ac condenser that is located in front of the vehicle near the radiator gets more air flow that helps it eliminate better the heat heat is extracted from the refrigerant when its compressed to be cooled down. Up to 8 cash back 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 ac system operation. The car is heating only when i am accelerating.

Display results as threads. Search titles only. At idle with ac off it seems to stay in the mid to low 300 range usually.

If the car is standing still on the parking lot heater blows cold air. Your air conditioner may be working but not at its intended power efficiency. As soon as you get moving it gets cold again.

If your blower only operates on its highest speed chances are you have the series type of blower motor resistor. Aannesley June 24 2009 951pm 4. 36 to use the AC gauges.

Air Conditioner Only Works When Driving What Could Be Wrong