Post your annoying bucking symptoms here

[powerranger262]

Since I have read through countless, and I mean countless posts about the buck that these trucks do, I wanted to start a thread dedicated to troubleshooting this problem. 3.0, 4.0, 4 cyl, whatever. Tell what yours does and anything that you have tried or heard to try to fix it.

Mine is a 02 FX4, 4.0L SOHC. 97,000 miles. When I am light on the throttle, it will buck or jerk the truck, until I let off the gas and hit it again to make it downshift. Mostly when going into OD. I always have to do this letting off the throttle thing whenever I am approaching a hill.

Things I have done/tried. New plugs, wires, IAC, cleaned TB and MAF. Replace my Airhog filter with stock paper one, fuel filter, idler and tensioner pullies replaced. Changed trans fluid and filter, TPS and PCV valve replaced.

Engine doesn't skip a beat besides this problem. Also, no CEL. I'm starting to lean towards a new MAF, or taking it to the stealership for the computer upgrade.

 

[AaronC47]

Bucking Truck,

I dont have the issue with mine BUT, Have you maybe considered changing or trying a different coil pack ? I am wondering if yours may have a crack somewhere. Also, If in recent past, you to were guilty also of running the gas tank way down till you had no choice but to stop for more then maybe your injectors are dirty or plugging up a bit, you could be pulling sediment off bottom of tank. The only real other thing I can think of is when my sister and brother in law were in Tampa Fl. he replaced motor, after, it didnt run well at all, come to find out their flexplate was cracked and really screwing things up.

 

[Big Jim M]

Then comes me!

I've never had an engine problem that I didn't repair and FIX immediatly. Only rarely have I allowed an engine of mine get so out of whack that it actually did buck and jump. But if it did it would have been repaired immediatly.
Big JIm

 

[powerranger262]

Tell me what it is and I will FIX it immediately.

 

[Big Jim M]

Ok then

Tell me what it is and I will FIX it immediately.

Have you cleaned the maf? Did that airhog (whatever that is) get the maf dirty? It does sound like the mixture is a bit lean when you attempt to downshift, or anyway it is time to downshift.
The maf could be not seeing all the air passing thru it.
Big JIm

 

[BRUTUS_T_HOG]

Since I have read through countless, and I mean countless posts about the buck that these trucks do, I wanted to start a thread dedicated to troubleshooting this problem. 3.0, 4.0, 4 cyl, whatever. Tell what yours does and anything that you have tried or heard to try to fix it.

Mine is a 02 FX4, 4.0L SOHC. 97,000 miles. When I am light on the throttle, it will buck or jerk the truck, until I let off the gas and hit it again to make it downshift. Mostly when going into OD. I always have to do this letting off the throttle thing whenever I am approaching a hill.

Things I have done/tried. New plugs, wires, IAC, cleaned TB and MAF. Replace my Airhog filter with stock paper one, fuel filter, idler and tensioner pullies replaced. Changed trans fluid and filter, TPS and PCV valve replaced.

Engine doesn't skip a beat besides this problem. Also, no CEL. I'm starting to lean towards a new MAF, or taking it to the stealership for the computer upgrade.

disable your EGR valve and see if the problem goes away. just try it

 

[powerranger262]

Yes, cleaned the MAF twice now. When I disable the EGR, should I unhook the battery and let things reset themselves also?

 

[BRUTUS_T_HOG]

Yes, cleaned the MAF twice now. When I disable the EGR, should I unhook the battery and let things reset themselves also?

no. just unplug the vacuum line and cap it. that will tell you if the EGR is the problem.

your symptoms sounds exactly like a bad EGR diaphragm. the computer commands the EGR to open under light loads.

if the EGR valve is electric then just unplug it

 

[powerranger262]

Sounds good, I'll go try it now.

 

[powerranger262]

Didn't work. There is also a EGR vacuum regulator that goes to the EGR itself. What would happen if I unplugged that?

 

[03ranger4x4]

my 03 started bucking when i changed plugs, drove me insane. I went to the store and saw i put regular resistor plugs in instead of the "iridium" plugs. Which i honestly think wouldnt make a huge difference.

Then as i replaced the plugs with the iridium plugs, i found that i cracked one of the insulators on the resistor plugs which cuased the whole problem in the 1st place. I even replaced the plug wires thinking that maybe from my removing them the first time one got messed up. Had no idea i cracked the plug until hours of frustration and a new wire set later. brightside, my plugs AND wires are brand new and shouldnt give me any trouble anytime soon.

 

[powerranger262]

I put Autolite double platinums in it. Does anybody know offhand if they are iridium plugs?

 

[wahl_7s]

use the same thing that came out of it its been my experience to only run MOTORCRAFT! my$.02

 

[powerranger262]

Finally got a CEL for cylinder misfire 3. Pulled my new plugs and found the ceramic was cracked. Put new one in, and it runs great again. So what I learned is to check over my new plugs for any sign on the tiniest crack before install.

 

[StratGT]

My 2009 Ranger did the same, after searching the forums and finding so many different opinions I decided to take it back to the dealer. End up being a bad ignition coil which went bad at only 10K? Seriously Ford only 10K? The Mechanic showed it to me and it burned a hole right through it. It got allot worse when I drove through a car wash and I barely made it out.