help with 5.4 fuel problem
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help with 5.4 fuel problem
The service engine soon light is on in my 2000 expy eb 5.4. The code is po171 according to auto zones code reader. Lean bank one. We live right next to the highway so everywhere we go is 10 mins of highway first. usually after this 10 mins the second or third time I stop for a light it will act like its not getting enough gas at idle it will bounce between 200 rpm and about 6-700 rpm if I put it neutral and give it a little gas it quits doing that and usually won't do it again that trip. Yesterday my wife said it started shaking badly on the highway at speed for a few seconds then quit and ran fine. This morning it ran fine 10 mins on highway then stop and go at least 6 or 7 red lights. I put some fuel injector cleaner in it about 3 or 4 tanks ago I used a different brand this time could this be a cause? If it was a vacuum leak would't it do it every time at idle? Thanks alot for any help you can give I hate to start throwing parts at it without any idea if it will work. Mike
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Joined: Dec 2001
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From: Louisville,Ky.
Sounds like your PCV hose elbow going into the rear of the intake manifold has failed. Pretty common on late model Ford. They get soft and crack causing a vacuum leak.
You might also want to spray the filiments in your MAF sensor with brake parts cleaner or TB cleaner.
You might also want to spray the filiments in your MAF sensor with brake parts cleaner or TB cleaner.
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Thanks lxman. I did the obvious today put on a new fuel filter and checked the fuel pressure. I read in a search of this site that the dipstick not being seated properly will cause a problem and mine wasn't seated maybe I got off lucky. I think I will clean the maf as you suggest and I'm trying to build the courage to to the plugs but every time I look at them I wonder if my patience will hold out for them. ( I tend to throw wrenches when I get frustrated).
