rough idle and lean code
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rough idle and lean code
I have a 2000 f250 superduty 4x4 5.4 liter.At idle it runs rough and misses.I am throwing a system lean bank 1 code.The rpms fluctuate up and down.While driving it still has a slight hesitstion and power is down with poor gas mileage.I have changed all fuel injectors,cleaned maf,replaced pcv and checked hose for crack/leak.I Also replaced the fuel presure regulator.Fuel pressure is about 38# not running.The coils have been replaced with accels about 7 months ago.just changed the plugs about 2 months ago but going to do it again.Any advice anyone has will be greatly appreciated.Ive already done searches and havent found anything to cure my truck yet.Thanks in advance to any suggestions.
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Joined: Sep 2006
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my truck did something similar. there is a plug on the bottom of air filter housing. mine had poped off and was sucking in unmetered air. i had to permitex mine on to get it to stay. that might be something that you'll want to check. good luck
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Joined: Jan 2004
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From: St Louis
Originally Posted by FatDutchMn
Will this rough idle from the PCV have an effect on gas mileage?
Steve
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6th Gear
Joined: Jun 2022
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From: Menifee
SAME PROBLEM
Any solution??
For months I’ve had random misfire problems and engine too lean codes. I changed coils and plugs and it was better for a day before engine light came back on and symptoms returned. Rough bouncing idle, lagging power especially from 40mph to 60 and uphill, mpg loss, light will flash when trying to accelerate at higher speeds. Changed PCV valve and hoses after mechanic found small vac leak. STILL same symptoms persist. Mechanic supposedly checked MAF sensor and other easily accessible potential suspects. Idk what to do. I’m novice and am trying to learn everything i can to save my mobility. Is it wiring to coils? Fuel injectors? Fuel filter? 2 mechanics so far have tried and failed to find solution. Please be patient with my ignorance. Thanks for your time
2003 Navigator 2WD 160,000m 5.4L
For months I’ve had random misfire problems and engine too lean codes. I changed coils and plugs and it was better for a day before engine light came back on and symptoms returned. Rough bouncing idle, lagging power especially from 40mph to 60 and uphill, mpg loss, light will flash when trying to accelerate at higher speeds. Changed PCV valve and hoses after mechanic found small vac leak. STILL same symptoms persist. Mechanic supposedly checked MAF sensor and other easily accessible potential suspects. Idk what to do. I’m novice and am trying to learn everything i can to save my mobility. Is it wiring to coils? Fuel injectors? Fuel filter? 2 mechanics so far have tried and failed to find solution. Please be patient with my ignorance. Thanks for your time
2003 Navigator 2WD 160,000m 5.4L
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3rd Gear
Joined: Jun 2025
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Rough idle issue
Any solution??
For months I’ve had random misfire problems and engine too lean codes. I changed coils and plugs and it was better for a day before engine light came back on and symptoms returned. Rough bouncing idle, lagging power especially from 40mph to 60 and uphill, mpg loss, light will flash when trying to accelerate at higher speeds. Changed PCV valve and hoses after mechanic found small vac leak. STILL same symptoms persist. Mechanic supposedly checked MAF sensor and other easily accessible potential suspects. Idk what to do. I’m novice and am trying to learn everything i can to save my mobility. Is it wiring to coils? Fuel injectors? Fuel filter? 2 mechanics so far have tried and failed to find solution. Please be patient with my ignorance. Thanks for your time
2003 Navigator 2WD 160,000m 5.4L
For months I’ve had random misfire problems and engine too lean codes. I changed coils and plugs and it was better for a day before engine light came back on and symptoms returned. Rough bouncing idle, lagging power especially from 40mph to 60 and uphill, mpg loss, light will flash when trying to accelerate at higher speeds. Changed PCV valve and hoses after mechanic found small vac leak. STILL same symptoms persist. Mechanic supposedly checked MAF sensor and other easily accessible potential suspects. Idk what to do. I’m novice and am trying to learn everything i can to save my mobility. Is it wiring to coils? Fuel injectors? Fuel filter? 2 mechanics so far have tried and failed to find solution. Please be patient with my ignorance. Thanks for your time
2003 Navigator 2WD 160,000m 5.4L
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