86 Parisienne

I'm having an issue with the car when it shifts into third gear. It goes through first and second without any issues, and the engiene revs fine and starts up and seems ok. When I drive it goes up to 35 without any issues and I can hear it shift through the gears fine. Then it hits third gear and it seems like the engine looses power. I can floor the gas pedal and it will not go any faster then about 35. The engine at this time sound like it is ideling really low. "won't throttle up" is how my buddy described it. I went to the Advanced Auto and the guy there suggested that the issue may be a Vacuum line leak. The guy there told me that he could hear one leaking. My buddy and I took a look and figured that what he was hearing was the air in the intake manifold. On top of that when you take the oil cap off there is exhaust comming out of it. I guess the question that goes with all that is this. Is the idea of an vacuum sucking in air most likley what is wrong. If so, where or which line would it be, what would i look for. And for the exhaust in the oil, is there an easier way to aliviate that without having to rip the enitre engine apart? The vehicle specs are as follows, It is an 1986 Pontiac Praisienne Brougham with the 5.0L V8 307 engine. Any information would be helpfull. If you have anymore things that you need to know, just let me know.

~Brett

If you had a vacuum leak that bad, it would not idle, this sounds like a blocked cat or muffler, drop the engine pipe from the manifold and drive it. And what did you expect AZ to do for you, this is not a repair shop, forget about dealing with them for repair/diagnostic issues. BTW, very good description of the problem, not often seen here.

make sure you have vacuum to the pcv valve & its not clogged.

If you had a vacuum leak that bad, it would not idle, this sounds like a blocked cat or muffler, drop the engine pipe from the manifold and drive it. And what did you expect AZ to do for you, this is not a repair shop, forget about dealing with them for repair/diagnostic issues. BTW, very good description of the problem, not often seen here.

I went to AZ because i am in a matter of my nerd terminology, a noob at cars. I was hoping that they would know more then I. Which they "seemed" to. I will try to see what I can do with dropping the engine pipe. I have had several people suggest it may be an issue with my Spark Plugs. I did just change them, but not my wires. And i didn't gap them either, which i know was foolish of me to not do. I have some experience on working on Lawn Mower engines, but thats about it. I plan to take it into work tomorrow as well, one of the guys there is quite familiar with these older cars, or so he says. I work at Discount Tire, so I have trust in some of the guys there that they are definelty mechanicly enclined in cars. I will post my results and finding here as well after i get her fixed up and running good. Thank you for your compliments, i will make sure to describe as much as i can. I used to be a computer tech, i know how frustrating it is to have little or crappy information.