Screaming noise that goes away when I accelerate

My car stared to make this horrible screaming noise like a bad belt when I was on the freeway. When I would accelerate the slightest it would go away. Take my foot off of the accelerator, the noise would start again. I pulled over then the check engine light came on. I had it towed home. HELP!

Was the noise coming from under the hood?
From one of the wheels?
From underneath the car?
Just telling us that the car was making a screaming noise does not give us a whole lot to go on, unfortunately.

The illuminated Check Engine Light (CEL) may be a clue to the “screaming” problem, but even if it isn’t, the CEL is telling you that something is wrong and needs to be rectified. You can buy a code scanner, bring it home, and connect it to the car’s OBD terminal in order to determine what trouble code(s) have been stored. Then, post the codes here for further guidance.

I am curious about your mechanical qualifications. Are you able to repair the car yourself? If not, why didn’t you have the car towed to your mechanic? That way, you would have paid for just one tow instead of two tows.

I pulled over then the check engine light came on.

 That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.


I was also going to suggest driving the car to Auto Zone or another parts retailer, but then I gave some thought to the mystery symptoms as well as the illuminated CEL. I think that the OP’s act of having the car towed home, rather than to a mechanic, may indicate that the OP is not comfortable driving the car at this point–and that may be a valid reaction on his/her part.

Overall, I think that the OP should just bite the bullet and pay for a second tow to a competent independent VW mechanic, but if he/she does not want to do this just yet, then it will probably be necessary to buy a code reader. Ultimately, the car may have to be towed anyway, but nobody knows for sure at this point.

Thank you everyone. It was the PCV Valve. I guess there is a problem with some of the Passats and the PCV Valve.

PCV valve is one of the last things that I would have suspected.

How many miles are on the Passat’s odometer?
Was the PCV ever previously changed?

Personally, I like to change my PCV valve every 3 years or so. They are so cheap that it is worthwhile to just go ahead and change them before problems develop.

Incidentally, you should have the oil changed a.s.a.p., as a fouled PCV valve could have led to contamination of the motor oil.

I only have 40,000 mile and the car is 2 years old. I had a full tune up done just incase. I have never missed a service on my car. Needless to say I drive a bit. Kinda shocking isn’t it.

BMW has their version of a PCV valve and they “moo” like a cow when ruptured. They don’t look at all like a domestic PCV valve and are pretty expensive,parts and labor, nothing to replace “just because”.

The screaming noise would have been the vacuum leak caused by the PCV failure. The check engine light would have been caused by the vacuum leak. Makes sense.

Only if the vacuum leak caused a misfire. That’s the thing about vacuum leaks and codes, they don’t appear until they cause something else to go out of range or a misfire, meaning there is no code “vacuum leak”.