4.6 Fuel Injection Problem

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Sep 12, 2008 | 07:04 PM

danlee

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4.6 Fuel Injection Problem

My 2002 Mountaineer with a 4.6 AWD has a light throttle miss. It has 89,000 miles, but I just changed the spark plugs. It started missing before I changed the plugs.

It feels like a Fuel Injection problem. I have tried 3 cans of Shell Techron Injector cleaner and still have a problem.

Has anyone had a similar problem?

How was it resolved?

Sep 12, 2008 | 09:24 PM

LxMan1

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From: Louisville,Ky.

Does it have COPs? If so, did you change all of the coil boots and use dielectric grease?

Sep 12, 2008 | 09:32 PM

danlee

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It has COPs. I used dielectric grease, but I didn't change the boots. The boots and wires looked OK.

Sep 13, 2008 | 01:55 PM

LxMan1

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Try cleaning the MAF filaments with brake parts cleaner. Perhaps they are a bit dirty. Just spray them down, but do not touch them.

Sep 13, 2008 | 08:17 PM

danlee

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The air filter is fairly new and clean. I'll try cleaning the MAF.
The fuel filter has never been changed. It should be changed every 30K miles. It was serviced at a dealer at 60K, including a tranny fluid change. They might have done the fuel filter at that time, but I don't think they did.
If I could find the fuel filter I'll change it. Any idea where it might be located?

Sep 13, 2008 | 08:54 PM

rplatt56

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Have you tried running Seafoam through it to clean the carbon out of it good?

Sep 13, 2008 | 09:31 PM

danlee

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I have used Chevron Techron Fuel Injector cleaner in the tank. It might have helped a little. I am on my 3rd treatment with the Techron. At this time, I have spent about $20.00 on chemicals, and still have a problem. I'll try the Seafoam in the tank.