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Question I have a 2004 Expedition 4.6 Eddie Bauer with 90,000 miles. It has been hard to start for the last few months. I have changed my plugs, air filter and fuel filter. It seems to start great when it’s cool outside (like this weekend in the A.M.) but after it gets warm outside it is hard to start? My battery and starter are good, turns over fast, just won’t start the first try, usually the second try though…Any help would be appreciated…BTW, I just ordered a fuel pressure tester to make sure I don’t have a leaking injector and I also made sure I had no trouble codes…. Thanks Ron P.

I suspect that if all is well with the fuel delivery system then you MAY have carbon build up. (Please go to my website and click on tech training to see the tests that are needed on the fuel delivery system.) Yes, the dreaded enemy of ANY engine is carbon and dirt. Carbon is a by product of burning fossil fuels in your engine. This “byproduct” of carbon MAY have built up on the back of the valves and the top of the pistons. So when you try to start the engine, the dry carbon “soaks in” most of the fuel causing the engine to idle rough or long extended cranks or stalling when first started. I would suggest that you seek out a professional repair shop that can perform a professional fuel induction cleaning. At my shop we use a Motor-Vac type fuel delivery cleaning machine. This machine will clean pistons, piston rings, intake valves, fuel rail, injectors, upper plenum chamber, throttle plate, EGR system and catalytic converter. The Motor Vac system does more than “push” cleaner through the injectors. It starts cleaning the fuel system BEFORE the car is started by surging the fuel back and forth through the fuel rail. This process removes any deposits that have gotten past the fuel filter. These deposits restrict the volume of fuel your injectors are designed to receive and inject into the engine. Regularly adding injector cleaner to your fuel will help slow down this problem after you get it cleaned professionally. Or better yet, use fuel that has detergent additives to prevent formation of carbon deposits. According to automotive engineers I have talked to, in as little a 900 miles non-detergent fuels can “carbon up” your engine. The best analogy I can give is like getting your teeth cleaned professionally. You see a dental hygienist to get the “hard stuff” scraped off. You keep the “hard stuff” from getting so big by brushing and flossing your teeth. Using detergent fuels is like brushing and flossing. Getting your injectors cleaned professionally is like seeing your dentist, just a lot less painful! James


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