I have a 96 Chevy G10 van with a 5.0. For a while I have suspected the vehicle may have had an exhaust leak. However, I also suspected the leak may have been around the manifold, and unfortunately, I am not really sure how to find a leak at that particular location (no lift for one thing). Eventually one shop reported a small leak on the right exhaust flange, but could not repair it. While, I was quite happy because this seemed to be a reasonable solution to some long running driveablity problems, both the shop that I had hoped would repair it and another were unable to find the leak.
As such, I have a few questions relating to leaks around the manifold of an engine.
First, could a leak in that location cause the following issues: ragged idle, loud engine noise (particularly during acceleration when cold), strong exhaust odor outside the vehicle, vibrations or shakiness felt in steering wheel at higher speeds, and sluggish acceleration.
Second, how do the symptoms of a leak upstream the O2 sensor differ from those downstream it (if at all)?
Finally, how can the average individual go about finding such a leak given that accessibility to the pipes is not ideal?