It probably means that you have an air leak somewhere. I know that's obvious and I'm really not trying to be a smartass.
Many of these leaks emanate from the windshield, the side windows or the outside mirrors.
If you can get a friend to take a ride with you, he or she may be able to localize the noise to one area or another. Once localized, you can try putting some tape over/around the suspected area to see if it goes away. That will help you to know if you need new window seals, for example.
I've heard of cases where this kind of noise is produced by the heat/AC system. Try playing with the controls while you're driving to see if you can change or eliminate it. (drive carefully, of course!)
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Have a look at this webpage; http://consumerguideauto.howstuffworks.com/1995-to-2005-pontiac-sunfire-6.htm It has a pretty good history of Sunfire changes and options. FriPilot
should be between 30 - 45 psi
It's between the engine block and the cylinder head.
The price for a new exhaust system for a 1995 Pontiac Sunfire is between $110 and $253, depending on the brand chosen. The MagnaFlow is one of the more expensive brands.
The fuel filter on a 2002 Pontiac Sunfire is in the rear between the fuel tank and the rear axle. By the way its under the car and easy to change takes about 10 minutes.
If the passenger seat to a 1998 Pontiac Sunfire is stuck forward, it's important to look for any interference between the track and rail. It is possible that when the seat moved forward the seat moved over the head of the mounting bolt.?æ
I assume you are referring to between the engine and the firewall. There are 2 heater hoses in that location.
Look to the left side of the driver's seat on the floor. There should be a lever between the seat and the door sill.
what i did for a ground on my girlfriends 96 sunfire was in the trunk there are hooks that hold the cargo net and the carpet down. unscrew it and just place the ground cable in between the bolt and where it will be screwed into that works fine.
I had the same problem with 2 cavaliers of mine ( which are basically the same as a sunfire) and my suggestion is the head gasket is bad or u have a cracked head most likely in between the valves.
That filter is hard to get at. Look between the rear of the engine block and the fire wall, near the bottom of the engine on the passenger side.