I just installed a chrome edelbrock air filter on my 92 brougham 5.7, and it gave me the check engine light....I was wondering what caused this...Vaccum leak maybe?? (there were 2 tunes attached to the original air box)
There is one vacuum hose that runs from the vacuum port on the driver's side of the throttle body. This controls the stovepipe heating unit for better cold driveability. You've essentially got a vacuum leak in the engine without it. Second is the IAT sensor. This plugs into the bottom of the stock unit pointing up. You want this, the computer relies on input from this to properly advance the timing, if memory serves me correctly.