there is a problem with my 1990 pickup that i cannot figure out... when the pickup idles it idles really high and when i put my foot on the brake the idle starts to ''lope'' or ''pulse'' and i cannot figure out the prob... if anyone could help that would be great!! thanks!

 

That would be a vacuum leak. Perhaps bad/leaking booster, or check valve?

 

I seem to recall seeing a post with the exact same symptoms recently - did you search?

But x2 on the vacuum leak as a really good place to start