1996 Audi A4 Quattro air conditioner works but not the heater

SOURCE: 1997 audi A4 heater blowing cold air

Sounds like one of two things has happened - either the heater core has gone south or your thermostat is stuck wide open. The t-stat is more likely as the A4 is known for issues such as this. My 99 A4 currently has the t-stat stuck partially open, so my heat production isn't quite what it should be. I did a timing belt on a 30v Passat a few weeks ago (same engine that I have) and it had the same condition as my car. Once the new thermostat was in, you could set the temperature to 75 degrees with the heat on the floor vents, and cook hamburgers on the floor mats.

Change your thermostat and you should be good to go. I don't know if you have the 1.8T or the 2.8 V6, but if you have the 1.8T, go to www.audidiy.com or www.audiworld.com and look in their tech procedures - there's a photo-referenced step by step on how to do it on the 1.8T. For the 2.8 V6, you have to open the car's front end as if you were doing a timing belt - the thermostat is behind the belt. You don't have to remove the timing belt to remove the thermostat, but if you're going that far in, and you haven't just recently done the timing belt service, you might as well spend the money and do it now rather than pay all that labor again later.

If you're in northern PA or southern NY and want to take a drive, I can do the work for you in an afternoon - otherwise, find a local shop that specializes in european cars and have them do it - it'll be a few hundred dollars less than if a dealer does it, and they'll do the job very well. Don't just go to any old shop - guys that wrench on Chevys all the time aren't the ones you want working on an Audi. They're good mechanics but there are things about the Audi that they likely aren't going to know to do.

If you do the work yourself and you want some pointers on it (it really is an easy job), reply here with an email address and I'll email you and talk you through it. You will need to pick up 3 liters of G12 coolant though (the pink stuff) from a dealership, or order it from www.ecstuning.com (midwest), www.purems.com (west coast), or www.germanautoparts.com (east coast). AutoZone doesn't sell it so you'll have to source it yourself. Those companies also sell the thermostat as well as kits with the timing belt service parts, so you can order that stuff from them as well. And if you do that, don't spend the extra $170 for the cam locking tools - they're 100% unnecessary.

SOURCE: 1997 audi A4 heater blowing cold air

You will have to change the heater core. 9 out of 10 times, when the heater is not heating the air, it is a bad heater core.

scott rimmer

• 162 Answers
• Posted on Mar 04, 2009

SOURCE: we have an audi a4 2.6cc , the heater only blows

sounds like the thermostat is not functioning correctly? either that or not in at all? thus making the water which would normally warm up quickly, warm up extremely slowly and on really cold days not at all? with a 2.6 engine your car shoudl warm up in record time?

SOURCE: 1997 audi A4 heater blowing cold air

You probably have a leak in your oil cooler. This is causing the oil to bleed into your cooling system causing the "thick brown liquid". This in turn will also cause your engine to over-heat since the cooling system is contaminated.

SOURCE: My audi a4 is blowing out cold air even when the

heater core clogged or heater valve