I have a 95 pontiac bonneville se with 146450 miles on it. The oil reads full. I don't have any leaks or so it seems. I was driving my car one day and had it stall on me 3 times. since then i've been noticing a whistle sound coming from the engine compartment and hesitation from taking my foot off the brake and onto the gas. I put and held my foot on the brake and noticed when i pushed on teh gas a little bit it seemed to surge. I was told this could be one of three things. But that doesn't help. I was told the Head Gasket, Intake Manifold, or just a vaccum hose. What should i do.
Thank you for looking at this.

Start looking fo vacuum leaks first, did you have the pcv replaced recently, one of the rings may be missing, common.

i bought a new pcv valve but didn't have time to put it in. This pcv valve is the origional from 95. How do i replace this also. I noticed that the vacuum hoses have some wear cracks on it but can't feel air or nothing come from there.

Pcv is under the map sensor.

ok i put in the new pcv valve. The hesitation stopped and most of the stalling. it runs fine but it still whistles when it gets warm. What do i do, to get it to stop whistling.

Someone has to listen to this at the car to track this down we can only guess from here.

First the 95's did not use a Map sensor... This appeared on the 96's with OBD2..

Second, when you replaced the PCV valve was there an O ring on the PCV valve as well as the PCV cap? If you are missing either one of these O rings it can and will cause issues..

I listened to the whistle and came to the conclusion it was by the upper manifold an near the back of the engine. Can't figure out where exactly high pitch, but so many wires running everywhere, only hear it when its hot.

PCV valve had oring, correctly in place and the cap is also on. Runs better. had problem with low idle in drive. fixed my problem

First the 95's did not use a Map sensor... This appeared on the 96's with OBD2..

Second, when you replaced the PCV valve was there an O ring on the PCV valve as well as the PCV cap? If you are missing either one of these O rings it can and will cause issues..
Correct, I missed that.

the noise sounds like its coming from the right side of the engine.

ok i checked my pcv valve and noticed i have one ring it looks like only for the top, where do i go to get the other one. Thanks.

i listened to the car and i believe i still hear the whistling noise. can the missing o-ring cause a vacuum leak somewhere else.,