Sharp whistling noise

For a month or so my 2003 PT cruiser, with 50,000 miles, has been making a very sharp whistling noise. It sounds as if it is coming from the engine area. Can anyone tell me what the problem might be before I take it to the repair shop.

Are there any other issues, such as a rough idle, loss of engine power, or loss of brake assist?

In the absence of any significant supporting information, I am going to take a few WAGs:

Vacuum leak?
Loose intake manifold?
Leaking power brake booster?

Sometimes, a cracked throttle body will cause that. Alternator bearings or belt bearings, Timing belt tensioner bearing. Power steering. Squealing belt.

I have noticed the idle seems rough.

It’s always a good idea to report all of the symptoms when you post your question. A vacuum leak or a loose intake manifold could both produce a rough idle, as well as a whistling noise.

I guess that I might as well ask this question also–Is the Check Engine Light illuminated?

No the engine light is not illuminated. The engine light did come on a couple of times and then went off. I thought I might have a short in the dashboard. A few months ago the break light would come on when accelerating from a stop and then go off. Now it usually stays on (the hand brake is not engaged). Then my radio/CD quit working, then it would be on and off. Now it is working. A couple of weeks ago the oil light came on a couple of times when accelerating from a stop, but went out quickly. Has not reoccurred. The oil is full.

You have major issues with this car that you are not attending to, and the result is not going to be good.

When the CEL came on repeatedly, you should have had the car’s OBD II system scanned for trouble codes. That could be related to the rough running of your engine. It is even possible that the light has now burned out and that the situation that caused it to illuminate is still present.

The constantly “on” brake warning light is most likely an indication that your brake fluid is low. Since this has been going on for a few months, it is almost a miracle that you are still able to stop the car. Brake fluid levels drop because of two possible scenarios–either a leak in the brake hydraulic system, or badly worn brake linings. Either of these scenarios can leave you with no ability to stop the car–especially when the situation has not been corrected after several months.

When the oil light came on repeatedly, that was a warning that the engine’s oil pressure was dangerously now. The light is not an indication of the level of the oil in the crankcase, but rather, the pressure at which the oil is being fed to the bearings. Damage could have been done by failure to shut down the engine immediately and then taking the car in for examination when this situation first occurred.

You are concerned about a noise that is likely not very serious, while I am concerned about the imminent loss of your brakes (with possible catastrophic results) and possible damage to your engine.

Warning lights should never be ignored, even if they stop lighting up, but to ignore a brake warning light that has been glowing in your face for several months is…not very bright behavior…and this level of negligence borders on criminal behavior. (If you got into an accident and it became known that your brake warning light was illuminated, you would be considered to be extremely negligent. If I was the attorney representing someone whom you injured, I would go for everything that you own–now and in the future.)

All-in-all, you need to get this car to a well-reputed mechanic NOW in order to have all of these problems fixed before you kill someone and/or destroy your engine. Trust me, the noise that you have been hearing should be the least of your worries.

Does the whistling change pitch when turning? There is a TSB on a whistling sound from power steering. TSB 1900104. Maybe someone with full access to the TSB info could provide more info.

Update – The problem was with the lower gasket. Replacing the gasket was covered by the power train warranty.