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Gassy smell on fuel injected truck?

Today I was out test driving trucks. I found a truck that I fell in love with down the street from my mom’s. It is a Ford f150 with a 5.3L Titan V8 engine with 4 wheel drive. When I went to test drive it with the initial turn of the key it smelled of gas but quickly went away. When I went down and had the step dad take a look at it we smelled it again but it went away even quicker the second time.

It has been sitting for 6mo prior to this drive other than it moving from Point A to Point be about 3 months ago.

Might I also add… I bought the truck. My brother in law asked me if it was fuel injected and had that smell, I said “yes”. He said I would have a big problem. Do I?

Have seen this a few times… In most cases it was loose spark plug. Also inspect for wetness around the fuel injectors (easily seen from top of engine) If vehicle runs rough following startup, very possible leaking fuel injector. If leaking injector is present, this needs to be addressed immediately… Leaking injector/s can damage cat converters and potentially hydrolock the engine.
In the field we use a small portable combustible gas detector to identify these conditions… The tool is about $160… A little pricey for 1 one time gig, but the best way to know for sure.

If you attempt to retorque the plugs I would highly recommend decarboning the engine using a top engine clean. Motorcraft works well, so does the MOPAR (Chrysler cleaner) (Both are aerosol). This is highly recommended because the spark plugs can seize and break when trying to turn. The cleaner is not full proof but does a great job of softening the carbon holding the plugs.

It is also recommended to use a torque wrench to verify that the plugs are installed properely. With a little effort, I think this should be an easy fix. Then you can enjoy the new toy