Start up issue
 

Hello! I have a 2002 mustang gt 4.6 manual and every time I go to start it the starter will try an the engine will turn over and almost start and then backfire and quit. It will do this once or twice and then start, after I get the smell of gas. It's more an inconvenience since it just started to happen and always used to start up almost instantly. What could this be?

Could be a dirty fuel filter, dirty injectors, or bad gas. When is the last time you changed the fuel filter?

It's not bad gas I've never had a gasoline problem from where I fill. I have never changed my fuel filter my car only has 80000 km.

change the fuel filter, get plugs changed, add some injector cleaner, do all the normal things to get a tune up.

If that doesn't work, replace the alternator. Sounds weird, I know, but I had the same backfiring problem, and after lots of replacements and cleaned bits, including a new computer for the car, a 5 minute swap of the alternator took the problem all away.