Where is the air pump located on 2000 43L jimmy came up with secondary air injection malfunction?

this is a pretty common question/problem, so here's what i answered to someone else (your 2000 is the same): on the 2001 gmc jimmy 4.3L v6 engine there are two air pump check valves: there's a pipe (about 1" diameter) that comes off each of the exhaust manifolds. the check valves are screwed onto those pipes. then a rubber hose (about 1.25" outside diameter) is clamped to the front of each check valve and connects to the air pump, which is hidden behind the vehicles grille in front of the radiator. typically, if you need to replace these (the life expectancy is about 3-4 years), it starts a chain of events that might be as follows: during the wintertime, water from the exhaust leaks through the worn out one-way check valves, and ends up in the air pump. the water freezes, and the ice jams the air pump, which may or may not ruin the air pump, but which usually blows the air pump fuse, which is impossible to find if you're rummaging around the passenger compartment fuse box or the under-hood fuse and relay box. it ain't there! so if you're looking under the hood leaning up against the front bumper, slide to your left around the passenger side headlight. now you should be looking at the battery, leaning up against the passenger side fender. look down between the battery and the fender. you have to push a few things out of the way, but there you will find a green 30 amp blade fuse (about 1" x 1" fuse--and $2.99 at autozone). this blown fuse should have triggered the check engine light and a dtc (diagnostic trouble code) of p0410 (secondary air injection system). for that vehicle there is a tsb (technical service bulletin) put out by gm (bulletin # 04-06-04-015; march 2004). if you want to print out some literature about all that I've mentioned just surf on over to http://www.obd-codes.com/p0410 for more links and documentation. my credentials: self-proclaimed auto mechanic for 26 years (sorry, no ase certification yet [but still trying to find time to study for the tests]) and college dropout (after 3 years of electrical engineering)--so, in other words, don't believe a word i say; just go to that website and get it straight from the horse's...

Answer

The air pump is located under the skid plate with the access hole for the oil filter.