Shutter when accelerating
 

I have a 2008 5.4 V8 Flex Fuel. When driving at about 50 - 60 MPH, and I accelerate, there is a shutter. I just had a tuneup and the shutter minimized, but still there. Prior to the tuneup, it was very defined, now its a slight shutter, but I can tell that it's still there.

Along with the shutter, when I'm at a very slow speed, and try to just ease up to something, i.e. my mailbox, the truck nearly stalls. Again, this minimized after the tuneup, but still there.

The tuneup helped, but there must be something else that needs updating. Any thoughts what else I can look at?

Thanks

Daryl

What EXACTLY was done for the tune-up? What brand(s) of parts were used?

You need to look at the live data on a code reader under OnBoardMonitoring, I bet you'll get a misfire count on one or more cylinders. Then I'd swap coils around and see if the misfire follows.

The stalling at the mailbox...hard to say. I'd pull the throttle body and clean it thoroughly w TB cleaner if the problem persists after addressing all misfires.

edit: oh, and that's shudder in this instance

Tuneup was plugs only. I don't what brand the mechanic used. Being two part plugs, I wasn't about to tackle this on my own. He did say that the coils were fine, there was no misfiring and did not need to be replaced.

I'll clean the throttle body and see if that helps with the stalling.

And thanks for pointing out my typing. I guess I should proof read before pressing enter. :-X24

Daryl

Well I *suspect* you've got at least one bad coil OR maybe he was not as careful as he should have been during plug replacement. F150Torqued here has done an exhaustive write-up about the importance of keeping the plugs and even the porcelain clean of greasy fingerprints, and suggested cleaning the carbon from the plug bore with a basic wire and rag in a drill.

That said, I would get live data and swap coils as I said before anything else - ASSuming misfire counts present themselves. Note we're not talking about misfire CODES - that's a little different

It's possible to do this for only the cost of an inexpensive code reader....$30 on Amazon oughta get ya there and you have a tool for years to come

MISFIRE !
Run an OBDII Mode 06 diagnostic test and pay particular attention to "Misfires Counts By Cylinder", for both latest drive cycle and the moving average for the last ten drive cycles. Both are available in a Mode 06 report.

Have you changed the trans fluid in the last 50,000 miles? sounds like at slow speed the torque converter doesn't want to unlock - might have some issues in the trans.

THIS. Thanks a ton, I'd never heard of a Mode 06 diagnostic. I had just bought a bluetooth OBDII scanner and had Torque Lite, but it wasn't showing any codes, just a "precode" of P1131. I bought Torque Pro ($6), it autoloaded the Ford codes and a short trip later I found out I had a bad coil on cylinder 4 and one going out on 1. Gonna order the whole set of BraveX coils and swap them all out.

I had never heard of BraveX but it sounds sick bruh -- which is not me mocking you but indicative of their target marketing.

I see a set of 8 on Jegs for $130, or $60 on Amazon.

DO NOT DO IT!!

In case I wasn't clear, DO NOT DO IT!!

OEM Motorcraft or nothing. Seriously. (Denso is probably ok, too)

You're introducing FAR FAR more problems than you'd be solving by removing functioning MC coils in favor of cheapass tuner coils.

Personally, I'd replace the 2 setting a code and move on with life. Wear a mask as you can transmit COVID to the coils

Motorcraft or Denso coils, use nothing else. The coils may be just fine actually but the shop didn't replace the coil boots like they should have.

Actually, I have done a lot of research on these, several people have used these on Ford vans with the 5.4l and they are still going strong 3-4 years later. I have seen horror stories about cheap no name coils off Amazon, but I literally could only find one bad review and they bought the wrong ones.

Those are completely different coils used in the vans, so how did you get the correlation? The 5.4 3v was never used in a E series.

My '97 E350 has a 5.4. Not sure about the 3 valve, but that's the engine listed.

https://www.motortrend.com/cars/ford...conoline-e350/

^^^^^^^^^^^^^^^^^^^^
^^^ T H I S ^^^^
The 5.4's are VERY picky about ignition parts, or you will be plagued by misfires (random and otherwise) for the rest of your life. I'm not sure why, but this engine must operate on the upper fringe of the ignition system's ability to maintain successful ignition. Valve retard is used to effect exhaust gas recirculation, and lean fuel mixtures trying to extend the already poor fuel mileage. But whatever it is - DON'T DO IT. Use Motorcraft Plugs, Coils - and good coil boots, ALWAYS.

Congrats on getting Torque Pro. If you are inclined and sorta' computer neerdish - you can get one hella'of-a' lot of good _poop_ from the OBDII system on your truck by creating / downloading custom PIDs and creating neat dashboards. Search around here for Torque Pro and you'll find a number of different system diagnostic dashboards.

+1 for checking the misfire counts per cylinder and +1 on using ONLY Motorcraft parts.

I had some elusive misfires on all cylinders , a couple consistently more than others, during acceleration between 45-65mph.
The truck would buck and shudder under load going up hills or jamming it on the freeway, and it was getting progressively worse

Long story short, original coils were good, O2 sensor were good, fuel pressure was 'ok', no rusted out fuel module, and TPS was good. Fortunately, I didn't throw too many parts at it
other than getting 2 coils just to swap in the worst cylinders which didn't fix anything.

Fuel pressure suspiciously dropped 'below' spec under heavy load to something like 28psi if I remember right, but I've been unable to find any consistent spec to define what it should be.

Turned out to be premature sparkplug wear on my Motorcraft SP515 plugs. At the outset, I didn't think that was a problem
since I just replaced them 15Kmiles prior, but the gaps were worn a tad wider than spec (which I originally thought
was 'marginally ok' for the mileage, but still 'ok'.as I've never seen that to be a problem before)
.
I managed to crack a couple of coil connector plugs while taking them off, so those had to be replaced.. the darn connector
shells simply shattered from I guess 16yrs of heat and stress.

After swapping a new set of plugs, all has been good for the past 5K miles.
Get yourself a good Ford scanner like an Autoenginuity... it's saved my butt many times.

The coil connectors ALWAYS crack. They're stupid $ at parts houses 'cause they know they have you over a barrel. You can get 8 packs on Amazon for the cost of 2 locally, and while they're certainly MIC I'm not sure the quality is any worse than what you get at O'Reilly or AutoZone. I've started just keeping an 8 pack in a drawer at all times.

I'm not a fan of AutoEnginuity, it's way overpriced for what it is and their support is lackluster. I have it and regret the purchase. Any $30 reader will give you misfire data. AE can be rivaled by TorqPro or ForScan for a fraction of the cost.