Alright, I have a 2007 F150, 4x4 with the 5.4, 3V FlexFuel… Recently I have noticed that when accelerating, a 'jerking'/'shaking' starts.. It is not really consistently doing this, but its not really intermittent either.. It happens more often than not. And it tends to happen when accelerating 'normally'; when you stomp it and take off, it doesn't seem to 'shake'/'jerk'… This issue seems to be speed related, but I could be wrong.. The reason I say that is when I first noticed the issue, I left the truck in park and revved it almost all the way up (I would say redline, but according to the tachometer, it doesn't have a 'redline').. However, I am not convinced that it is speed related because I know engines/drivetrains will behave differently under load than they do at standstill/park/neutral…

To give you a better idea of what this 'jerking'/'shaking' feels like; the best thing I can think of to compare it to is the 'jerking' you feel in a manual/standard car when the clutch slips then finally grabs and sticks to the flywheel. That 'bump'/'jerk' when the clutch actually engages with the flywheel; that is what this feels like in my truck. It is definitely something either in the transmission, or engine; or at least feels like it is coming from that 'area' of the drivetrain. Doesn't feel like its in the rear end, definitely not a suspension issue or steering issue, no squeaking or whining noises coming from anywhere, no clicking noises or anything, no 'wobbling' or vibrations coming from anywhere either; just a 'shaking'/'jerking' feeling when under load..

It feels like to me that it's coming from the transmission, or possibly the flywheel/torque converter area.. The engine does seem to idle SLIGHTLY rough, but the rpm's aren't jumping up and down; it idles right around ~500-750rpm… But the needle doesn't bounce at all; it stays steady in spite of feeling the a slightly rough spot in the idle..

The only thing I have messed with recently with the drivetrain was I changed the tranny filter and some of the fluid; approx. 7quarts (I dont remember exactly how much it was I replaced, but it was enough to fill the tranny back up to where it should be after changing only the filter).. I DID NOT flush the tranny and when I checked the fluid level, I had the truck running and warmed up on a flat/level surface as to get an accurate measure and everything was topped off right where it should be..

Oil pressure and voltage both check out, all other fluids are topped off, no vacuum lines are dry rotted/cracked/broken/disconnected or anything, no sensors are broke or wires broken nor any bad connections (that I can see or have found at least); I am stumped…

I was out and about yesterday in it and the check engine light came on for the first time in a long time (in spite of not having any cats in the exhaust system) and there were only two codes (both of which I have seen before): P0175 and P1000… One says I need to drive the truck more (I have read into the P1000 code prognosis before; I am still lost on that one.. Can someone explain how to make that code away to me, please?) and the other says Bank 2 is too rich.. I am sure that the P0175 code is partially to fully due to a lack of cats in the exhaust.. Aside from there being no cats, everything else in the driveline and mechanically speaking checks out fine..

Any thoughts/ideas/suggestions? I have most every hand tool you could possibly imagine to work on vehicles; so IF I can figure the culprit, I am confident I can fix it… I just don't want to tear into my daily driver (and only vehicle) blindly… Thanks in advance y'all.

 

I will hazard you put the right oil and filter in the trans and didn't get any contaminent/dirt, dust, or water in it. I wouldn't red line the motor again though. Your eratic motor/trans may be the fuel pump module in the back. Take it down and see if the cover is corroded thru. The reason it won't complete its tests are the cats removal has messed with the O2 sensors and fuel system open/closed loops. One way to remedy is to get a tune shutting em off, ie. off road tuning or raise the downstream o2's above the exhaust flow.

 

That's correct; I used the right fluid and made sure everything was spotless in the fluid pan and all sealing, contact surfaces were clean too. I will check the fuel pump module first thing tomorrow and see what it looks like. I have a SuperChips Plug 'N' Play tuner and have tuned the truck a few different times; but I don't think that tuner will 'shut em off' exactly.. A dyno tune is in the future works for the truck though. In the meantime, I think I am going to put cats back in the exhaust. Aside from making it run right, I am also looking to move out west; in the event I can make that happen, I need the truck to be able to pass emissions laws and registration out west. So cats and tune are definitely in the future plans for it.. What do you mean by raising the downstream O2's above the exhaust flow?

 

You know the tune messes with the shifts of the transmission, put it back to OEM, see if it gets better. There are sleeves you can weld in the pipes to raise the downstream O2's up above the exhaust for better signal ratios. Going back to cats would X out the change in the O2 positions. But the downstreams may be cooked now and need replacements.

 

Hmm - you are running canned tunes? Do you have an aftermarket intake? If so, it's running too lean.

How many miles on the truck? You may need new spark plugs.

 

I didn't think the tuner would mess with the shift points/pressures, unless I told it too. Because there are options to mess with both of those.. Can raise or lower the shift point with respect to RPM's and speed. Can mess with the shift pressures individually too. I did retune it and set almost everything back to stock; the only things that I didn't set back to stock was the shift points. I set them to SLIGHTLY higher speed and RPM than stock.. But the shift pressure(s) and map, are back to stock. The only other feature within the tuner I have messed with and is set for 'aftermarket' is my tire size for speedo calibration… I have a 4" Rancho lift kit with 33" BFG's; so I have accommodated that set up in the tune as well.

As far as it running too lean, though; I have been told about that before… And yes, I do have an aftermarket intake on it. Strictly performance speaking, I have long-tube headers on it (Dynatech SuperMaxx long-tube headers), an SLP cat-back exhaust that I had to customize before installing (that's a long pain-in-the-a$$ story) and as a result don't have any cats in the exhaust, i have the SuperChips Tuner and a K&N Intake system.. I am surprised that it would be running lean though, cause every now and then I notice a LITTLE bit of fluid running out of the tails pipes, but I figured that was dude to the lack of cats, not necessarily due to running lean/rich…

Mileage? Just a couple days ago, it broke the 34k mile barrier… The truck is still like new… If your wondering how I managed to keep the miles so low for the past few years: I had a lawful run-in back in '09 on my crotch rocket (I sold it spring of '10; it was an '08 gixxer 1000) and ended up with a 3yr hard license suspension. The suspension is lifted 12/10/12… But anywho, I have looked at the spark plugs… in fact, I did the research and learned about them breaking off in the heads when you go to change them at 60K miles, and that the previous generation/model of modular engines had problems with the plugs blowing out of the heads. I figured with as little miles that are on it, I would beat the breakage to the quick and put some Anti-sieze on them. Well, I pulled the plugs, well, 5 of them anyway; 3 still broke in the heads… So I had to go get the Lisle tool kit to get them out… After a week of monkeying with the plugs, I ended up with some new plugs and all 8 Anti-siezed.

When I first noticed the 'shaking'/'jerking' thing, I took all the plugs out and did a spark test; I would have liked to have seen a slightly stronger spark from a couple of them, but they were all firing… And I definitely smelt fuel too; though I didn't check each injector, I am pretty sure none are missing fire..

As for the downstream O2's being cooked; I thought about that and I am really hoping they aren't… I have already replaced at least a couple over the past couple yrs… Its an easy sensor swap, but not exactly the cheapest…

Would running too lean cause the 'jerking'/'shaking', possibly? Between the intake and no cats in the exhaust, perhaps the PCM/ECU is 'totally confused' and this is the result??? I am just throwing some more ideas out there; I am really not sure what the problem is and I don't want to rule anything out yet… It seems that going cat-less was a bad idea though… damn...

 

Sounds like a missfire, the trans more or less works or not, much less intermittent problems are trans issues

 

A muffler shop can fix you up reasonably with cats and O2's operating properly. This will put the fuel system back in equilibrium going open/closed loop as necessary ordered by the downstream O2's data stream to the PCM. Timing, valve and ignition should also improve with the fuel system up to go. Maybe clean the Maf will help it too. Sometimes these 5.4's is its all in the vacuum leak.

 

I'm going to check and clean the MAF today. I was thinking about look at the fuel pump module in the rear as well, but the truck is garage kept and hasn't seen much road time in the weather; but I also figure it can't hurt to check anyway…

The issue with putting cats in cross over assembly is that they will have to be welded in; the net result of all the exhaust work is 3-pieces: the two headers and then a 1-piece header back exhaust pipe. If I were to take it to a muffler shop, I would be looking at paying an arm and leg for the cat instal. I'll have to borrow a welder from a buddy and go to town on it one weekend.

In regards to a misfire vs tranny problems; I think that is very possible, except for the fact that when I did the spark plug check, all spark plugs fired. The transmission seems to work just fine; shifts smooth and doesn't seem to shift too soft or hard.

Me and a buddy took it out just the other day to do some running around and it started acting up right when he laid into it a bit to pass a slow moving vehicle, up til the throttle was laid into, it ran smooth and just fine. I distinctly feel it down shift and whatever the 'jerking' is was noticeably stronger than the downshift. That was the first time it did it to that extent. That did feel kinda like a bad misfire on more than one cylinder, but then it went away and drove fine for a few miles. It did come back, but nowhere near as severely and was intermittent. It 'jerk' a few times, then drive fine for a bit, then repeat…

The only thing I can think of in regards to the misfire is that when I did the spark test, I didn't test all of the C.O.P.'s. Could one or more of those be bad? I wouldn't think a coil would go out with such low miles on the vehicle, but I suppose I have heard of and seen stranger things with vehicles…

 

I'd highly recommend if you are going to use that programmer without custom tunes, you put the stock intake back on it and do a Gotts mod. The intake has relocated the MAF and it's no longer metering correctly.

 

+1

Get everything back to stock (including CATs) and you will be amazed on how much better it will run.

 

I have no doubt it will run much better if I did all that. But I am not sure I have my stock intake anymore, I know I don't have my stock headers anymore, and the cats instal is still in order. I have a good friend that lives only a couple hours away that does nothing but custom tuning. Once the cats are installed, I was just going to take it to him and have him tune the hell out of it. In the meantime, if I do by some chance have the stock intake still, I'm going to do a Gotts mod. That seems ideal.

This 'jerking' that it does now, though, is new… I have had the exhaust and intake as they are for a while now, as in well over a year. It wasn't until I Anti-siezed the plugs and changed the trans fluid filter that it started acting up as it is now. I am stumped after having checked everything again.

The fuel pump driver/control module is also in perfectly good shape. No corrosion through casing or anything.

 

You might want to pull the cops and plugs back out - make sure the plugs aren't fouled, you may have gotten some anti-seize where it shouldn't be. If you didn't replace them when you changed the plugs, I'd replace the cop boots and make sure you use dielectric grease - but don't get any grease on the actual contacts or spring. Boots are cheap at rockauto.com.

I have also heard of these plugs cracking.

 

With dielectric grease inside the boot, where it belongs, it will get on the spring. However, this will not cause a problem.

I do agree with checking the plugs for anti-seize on the electrodes.

 

We are thinking along the same lines; spark plugs/electrode strap-gaps/etc. are where I am looking tomorrow. Fouled plugs and/or anti-sieze on the electrodes is possible; and I am hoping out of all the possibilities, it is just a fouled plug or something simple along those lines… When I anti-siezed them, I didn't replace the boots or anything; I only replaced 4 plugs (3 broke and I destroyed 1 just to see how it was pressed together). I used dielectric grease on the inside of the boots. Though I am sure a good cleaning when I look at them tomorrow wouldn't hurt. Any suggestions on what to ckean spark plug connections with? Ether?

Unfortunately, I don't have my O.E. intake. So a new one (probably will buy on ebay), is in order, followed by the Gotts mod, and new cats will be on order and day in my buddy's shop to instal them is in the VERY NEAR future…