Bucking at Low Speeds

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Hoos95

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I have a 2007 Eddie Bauer EL with 242K miles. While at low speeds accelerating the car bucks. While at higher speeds there is no issue. Spark plugs were replaced about a year ago.
 

1955moose

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As members have reported numerous times, please do a fuel pressure test, and use an obd2 scanner to bring up any trouble codes. Please post your or your mechanics results. Bucking is usually electrical, but not always. Keep in touch.


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docraymund

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If you can, check the vehicle speed sensor, crankshaft position sensor for loose or intermittent conections. If you know a tech who has an oscilloscope, much better. Also check the engine mounts.
 

tavern89

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I am having same exact issue. I have a 2007 limited EL with 104k miles. Ive taken to ford and two mechanics. Ford wasnt sure but thought it might be the torque converter , so I took it to transmission shop and they of course couldnt make any guarantees that was the problem until they opened it up . Mine occurs between 30-40 MPH the whole car shudders when accelartaing then it goes away . Driving 60 70 80 MPH the truck drives smooth and strong . Sometimes it will happen during city driving several times in a row then sometimes wont happen for days. Ive installed new spark plugs, coil packs, carbon cleaner, etc . Ive become an experiment for the mechanics and keep thrwoing money at a problem nobody can fix.
 

ricofrancois

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I had the same thing happen with my 07 XLT (105K). It was fixed after replacement of 1 COIL and all Spark Plugs.
It started doing it again almost a year later and a new Torque Converter fixed it.
 
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Hoos95

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Have been lazy and haven’t addressed the issue yet. But, the idle is starting to get rough and I’m getting a check engine light for misfires on cylinders 2 and 3. Spark plugs are still relatively new, so I’m thinking it’s the coils.

Any other suggestions?

Coming up on 300,000 miles!
 

ExpeditionAndy

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Have been lazy and haven’t addressed the issue yet. But, the idle is starting to get rough and I’m getting a check engine light for misfires on cylinders 2 and 3. Spark plugs are still relatively new, so I’m thinking it’s the coils.

Any other suggestions?

Coming up on 300,000 miles!
It could be the clutch in the transmission. When was the last time you changed the transmission fluid. A number of guys were having similar issues and changing the transmission fluid cleared things up.
 
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Hoos95

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It could be the clutch in the transmission. When was the last time you changed the transmission fluid. A number of guys were having similar issues and changing the transmission fluid cleared things up.

Transmission fluid has never been replaced. Is that a difficult thing to do?
 

ExpeditionAndy

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Transmission fluid has never been replaced. Is that a difficult thing to do?
You can drop the transmission pan but that only changes a small quantity of the oil. You want to get the oil out of the torque converter which holds most of the oil. The best thing to do is have the dealer do a complete transmission oil change. They punp the old oil out while pumping in fresh clean oil. You can also pull the transmission dipstick. More than likely the oil will be dark and have a bad smell, that is sure sign that it needs to be changed. You can also have the dealer look for metal shavings in the pan which indicates that the transmission is tearing itself up.
 

1997SCEBFEX

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couple things come to mind as you address multiple issues, some have been mentioned; not in priority order.

++ on MAF, sludged up intake, air filter, fuel filter
IAC
TPS
++ COPS; wouldn't do plugs w/o them IMHO.
balanced driveshaft? loss of wheel weights perhaps.
++ on trans filter and fluid change
Rear diff fluid and friction modifier if you have LS.

let us know what it is.
 

Atman246

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I was a ford trans tech back until 2005. The aode/4r70w transmissions had a torque shudder which Ford said was a fluid issue. Replace the fluid with the then new mercon 5 and usually the shudder would go away. Extreme cases would get a torque replacement. My 07 expy had a bit of a clunk on slow speed downshift and it turned out to be a software issue. A reflash and all is good. Just a thought.
 

Adieu

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If you have misfires its definitely not JUST the tranny lol

Typical causes of misfires:
Plugs, coils, injectors on corresponding cylinders


Oh and make sure the wiring is plugged in nice snug and clean into injectors and coils.
 
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