Strange Noise from engine and white smoke

[draven4099]

My wife has a 2003 PT Cruiser with approx. 52,000 miles on it. It seems like every 6 months, something goes wrong with this car and we have to take it into the shop. So, now something else is happening.

There is a strange noise coming from just below the engine. It only lasts a second, and is usually followed by a puff of white smoke. I have personally encountered this on two occasions. Once, while in park with the AC on, and the other while stopped, AC on, and just after we accelerated.

I was able to recreate this noise as the car sat in our driveway with the AC on. It sounds like a semi truck "engine braking", and it only lasts a second. I was not able to recreate the white smoke incident.

I dont know if this is related to the AC, but it seems like when we stop, the AC barely blows out any cold air. It also appears to idle, drop below 1000 RPM, something kicks on, and idles to where it needs to be.

I am not a car mechanic, but I have come to these boards before on another issue with her car. Any help will be outstanding. Thanks.

[slartyblarfast]

The noise is from your a/c compressor venting. The high pressure gets to high and vents. Most likely your cooling fan has stopped working. That makes the head pressure get too high because the condensor does not have any airflow.

[draven4099]

Originally Posted by slartyblarfast

The noise is from your a/c compressor venting. The high pressure gets to high and vents. Most likely your cooling fan has stopped working. That makes the head pressure get too high because the condensor does not have any airflow.

Is the fan making the semi-truck "engine braking" noise? It only lasts for a second. Maybe the fan is getting stuck? How much would this cost to replace?

I just need to know where to direct my mechanic. Luckily, he also owns a PT Cruiser, and knows some of my pain. Thanks.

[slartyblarfast]

No. The hissing is from the high pressure relief valve on the compressor. It's dumping freon because the pressure is too high. Not sure about the price.... Probably 300-500 dollars including recharging the a/c system.
Fan is not that hard to replace. There are multiple posts on how to do it.

[CREWZIN]

Originally Posted by slartyblarfast

There are multiple posts on how to do it.

In fact, I just put a "sticky" on the procedure on the top of this Tech & Performance section of the forum.

[draven4099]

So, the fan just needs to be replace? What is making the semi-truck "engine braking" noise? Im going to take the car into the dealer tonight, but I am just curious as to what the problem is and how long it might take. Thanks!

[slartyblarfast]

Originally Posted by slartyblarfast

The hissing is from the high pressure relief valve on the compressor. It's dumping freon because the pressure is too high.

Ummmmm......

[draven4099]

Sorry, sir. I just wanted to make sure. I just dont want this thing to cost thousands of dollars to fix. Thanks for your help!