2006 Explorer EB bucking at higher speeds when acclerating

[roveer]

I've got a 2006 V8 explorer 140k miles and have had a problem that I first throught was transmission, but now think is engine.

2 years ago I noticed when accelerating onto highways I'd get some hesitation/loss of power when really pushing it. Took it to the dealer and they said I had a burnt plug wire. Don't think the problem ever went away. Fast forward to now and the problem has gotten worse adn different.

At around town speeds everything seems normal. Good acceleration, no misfires, no bucking. When I go on the highway and start to accelerate on an on-ramp I get a tremendous bucking and engine hesitations. depending on the scenario I will also get a flashing check engine light which sometimes goes away, but if I allow the condition to persist will stay on. if I read it out with my OBC it shows p0300 which says randome engine misfire.

I origionally thought it was the tranny jumping between high gear and the lower gear. The bucking is pretty harsh. what I would do when this happened was to push a bit harder on the pedal forcing the tranny to jumpt down a gear, pick up the revs and that seemed to work. Now I'm noticing that the engine is hesitating when I do this and this is usually when the check engine light begins to flash. Sometimes i can get a clean downshift and clean engine revs and it works. I usually get the bucking when i'm in high gear and just about hit the point with the pedal that I should be downshifting.

Researching a p0300 there are a lot of possible causes (if this is even the problem), one of them being injectors or fuel system. I Jiffylubed the truck last week for an oil change and had them do the fuel injector cleaning when they put the fluid into the fuel rail and stuff in the tank. No changes what so ever.

Again, around town at 10-40mph no real problems, above 50mph, I have to manage the problem full-time.

Very concerned about taking the truck to the dealer as they will want to start changing all sorts of things. P0300 runs the gambit and I find dealers love to run up the "we'll try this" bill.

I think I read something about a sensor related to air intake that could/should be cleaned.

Any ideas what I'm dealing with here? Anything I can do to try and fix this?

Thanks,

Roveer

 

[Crocketts Ford]

Well, I'm glad I'm not the only one with this problem. I have some insight to your problem, but I will also piggy back on your thread since I am having similar problems with different symptoms.

When I first purchased my 2006 Ford Explorer Limited V8 with the 6 speed transmission I had the same problem you mentioned. When accelerating onto the highway my engine would do the same thing and the engine light would flash. Turned out to be a misfire from the codes. Took it into the dealership and they replaced some coil packs at no charge, but the problem persisted. The dealership was a little misleading with me, but eventually I found out it was the spark plugs since they would always dance around that subject. The dealership does not like changing out the plugs for this year engine because they break when you take them out due to a design flaw. I Read up on how to take them out with less of a chance of breaking them, but still broke 3 of them. I had to order a special tool for about $65 to extract the broken plugs which was pretty painless, and worked as advertised. It was the Lisle 65600 tool, and you can YouTube it as well. In the end I replaced all the spark plugs and that problem went away entirely. Out of curiosity I measured the gap of the old spark plugs and found them to be almost twice the gap they should be due to 90,000+ miles of wear. This was obviously the cause of the misfires.

Now for my problem....

Now at 135,000 miles I had a shudder in my transmission at about 45 mph that sounded like a rumble strip every now and again, but not constantly. Thanks to websites like this I found it to be the torque converter clutch. Some suggested a simple flush of the transmission before moving onto some more expensive fixes to correct the problem. I did this and had brand new tires put on all the way around about that same day. The shudder went away, but now in my final drive gear I get what feels like lag and surge in power when gently accelerating without the transmission shifting down. Feels sort of like bump.... bump... normal acceleration... bump bump. No check engine lights come on, and it only does it in this gear. All four tires are the same and new, and I removed the 4x4 fuses to see if the Auto 4x4 was kicking in for some reason. Still does it.

Anyone have any ideas for us?

 

[Crocketts Ford]

Bam! Fixed it. It was still a misfire in my engine, but was not bad enough to flag an engine light. So I replaced the coil pack boots and springs (about $40 from autozone) after finding that all my coil packs ohmed out between .6 and .9 Ohms (indicated they are good). I guess when it rains it pours. One less thing to worry about.

 

[reesew01]

Similar Problem

I have a 2006 Explorer Limited with V8, 2WD, 90K miles. I have the same shudder in overdrive that you describe. No CEL and my mechanic said no code detected. He wants to inject an additive into the transmission, I suspect the same stuff you had. Another tech suggested a problem with the torque converter and also suggested the additive first. Do you believe your shudder problem was the coil all along? Do you believe the additive had any benefit to the issue?

 

[Crocketts Ford]

I did not have any additive added to my transmission, and I do not fully believe in additives. I paid a transmission shop to clean and flush out the transmission, and then refill with proper transmission fluid. These transmissions are very particular to the fluid you put in them. I made the mistake of adding transmission fluid to my tranny that was called out as Ford Transmission fluid, but I later learned it was not the correct fluid. The transmission shop knew exactly what fluid needed to to go in there. Since doing this service to my transmission I have not had a single shudder. Remember, this fixed the torque converter clutch shudder that sounds similar to going over a roadside rumble strip.

If you feel like your engine is missing, which is more of a feeling in the vehicle and less of a noise, then I would look towards spark plugs, coil packs, and coil boots. It was right around 90K that I changed my spark plugs that was causing my engine misfire at the time. They do not have an adjustable gap, but I measured my new plug gaps and measured my old plugs. The gap was about twice what it should be at around 90K miles. If you go this route either have a mechanic change the plugs or read up on changing the plugs in this engine. Have the Lisle tool I mentioned in my post above, as I would put money on it that you may break at least one plug.

 

[reesew01]

Shudder

Thanks for the quick reply. From your description of the "shudder", I"m thinking my issue is different. No noise associated with my issue, only an intermittent miss while in overdrive. I'm using an independent mechanic and will steer him toward the plugs and/or coils. Thanks again.

 

[Crocketts Ford]

No Problem. I know these things can be frustrating. If the plugs have never been replaced I would start there. If it persists I would go to new coil boots since they only cost about $40 for a set of 8. At the same time I would ohm out the coil packs to see that they are in spec and change any that are not. At the very least record what coils are suspect and replace them if plugs and boots don't solve the problem.

Post any updates on your problem/solution.