AC not cold = head gasket problem?


#1

First, I’m just glad that there are folks out there willing to help someone like myself who has very little knowledge about cars.



I took my vehicle (Saab 9-3) to a local dealership because the AC is not cold. They looked at the same issue about a month ago and just filled up the freon and it was working fine. Now they are telling me that it could be a head gasket problem but they will need to do some more tests to verify.



Is this even possible? They are throwing around a price tag of 2-3K for the head gasket repair if indeed that is the issue.



Please help as soon as possible.



Thanks in advance,

mxi


#2

since this isn’t warranty work, why not take it to a AC shop? they will not gouge you like a dealer will. at least they will be honest about the head gasket (they don;t do them) so you will know the truth…

matter of fact. why take it to a dealer at all?


#3

Thanks for the quick reply cappy208!

This is the only “authorized” Saab repair shop in our immediate area without driving a good distance. So it is possible that the reason the AC is not cold could be related to a head gasket problem?

Thanks again!


#4

They are totally unrelated-- the only reason a bad head gasket will cause the AC to stop working is when it wrecks the engine.


#5

I can imagine no relationship between the head gasket and the A/C!


#6

Many mechanics are more then qualified to work on Saabs. Do what cappy says and take it to a AC shop. They don’t have to be Saab authorized…They are MORE THEN QUALIFIED to work on your car.


#7

The one way an engine head gasket problem would cause diminished A/C cooling is if the engine is overheating. A hot engine radiator will radiate heat to the adjacent A/C condensor requiring higher coolant head pressure to obtain liquification of the freon.

Hope that helps.


#8

They’re feeding you balogna. The AC system is, with the exception of the compressor being driven by the crankshaft, a system totally seperate from the cooling system. The engine’s systems do not exchange heat energy or disspate heat in any way whatsoever.

I agree with Researcher’s thoughts, but IMHO that amount of overheating would be significant and lack of mention of an overheating problem leads me to suspect that the problem is unrelated to a headgasket problem.


#9

Thanks to everyone for the fast and insightful responses!

Sorry, there is another thing I forgot to mention…the car is kind of rough when you first start it up in the morning and when it first idles, but the rest of the day it’s fine. Maybe that’s where the head gasket problem comes in?

Thanks again!


#10

There have been no issues with the car overheating at all.


#11

I’ve started a new discussion topic for the rough idle.
http://community.cartalk.com/posts/list/1318809.page

Thanks!


#12

There are ways to detect a bad headgasket, some easy. If the radiator bubbles with the cap removed and the engine running, that’s the combustion gasses being blown into the water jacket and migrating out. There’s a test strip you can buy to check the coolant for the presence of hydrocarbons in the coolant, again an easy check. And, there’s always a pressure leakdown test, where the cylinders are pressurized with air and their ability to hold pressre monitored. That last one is easy in a 4-banger but can be a pain on a V6 if the rear bank is hard to access. I confess to not knowing if the 9-3 is a four or six.

A headgasket breech will cause a rough idle, but it usually becomes more apparent under load, when the pressures in the cylinder are the highest. You will usually also detect loss of coolant, as the vacuum in the cylinder spikes on deceleration and the pressurized coolant (most that I know operate at about 15-16 psi) gets drawn into the cylinder and vaporized.

I’m still inclined to think they filled it with freon but didn’t find the leak. And the new freon leaked out through the same leak the old freon did.


#13

I had a 1999 9-3 and it had to have the head gasket replaced. They had a problem with them. I bought mine new and it had the worst A/C of any car I had. What year is yours?


#14

Usually (on most cars) the AC condenser is in front of the engine radiator, so if the engine is overheating, this likely wouldn’t even affect the A/C.


#15

In regards to the A/C problem, how much refrigerant did they add? (Refrigerant is the proper name rather than Freon).
Some refrigerant loss with age and time is normal.
However, this amount should be comparatively slight. If they added a substantial amount of refrigerant then they’re missing the problem, which is a leak that needs to be repaired.