Looking for help with an air leak.

[TM21fourT3]

So here's what's up...

Did my first lower exhaust manifold gasket job on my explorer, got through it alright. But, after it was all done, I saw what looks like a bike tire air cover thing on the ground, I think it goes somewhere in the car.

So I started the car up, and it's not running right, I brought it to my guy who had some free time, and he told me it's for sure an air leak (very, very reliable source). He said it could be something as simple as the cover thing (which I hope), or something as major as re-doing the whole job.

So here's my question....

Where are the spots on the engine that would require an air "hole" cover about 3/8" in diameter? Can someone draw circles on paint or something like that? - Please.

Also, what are ways to test for air leaks? He said to use a cigar and blow the smoke into the engine, but is there any other way?

Thank you guys.

 

[Turdle]

The "tire valve cover" goes on your fuel injector rail test port. There is no "air cap" that would allow air in, unless the cap is actually not threaded like an valve stem cap would be, but rather a rubber vacuum plug. Look at the "octupus" looking thing on the rear of the driver side of upper intake plennum. If you look real close you might find one metal nipple completely uncovered.

 

[awood]

There should be a vacuum diagram sticker somewhere in the engine compartment. If not, look in the "sticky's" at the top of this forum and there's a link for "91-94 schematic/diagrams". Open that up and scroll down a ways to see a vacuum routing diagram. Take one hose at a time and inspect it from end to end. You'll likely find more than one that needs replacing. If it's a bad enough leak, you will have a check engine light on with Lean fuel mixture codes and possibly other codes.

Turdle is right with the valve cap. It goes on the fuel injector rail, kind-of behind the alternator/ upper radiator hose/thermostat area.