Advice: Expedition running rough

[Jay5.9L]

Our 2010 Expedition with the 5.4L just hit 148k miles and was running fine. I had ford do the tune up with new plugs and a coolant flush. Now it has a intermittent miss. My wife describes it as like it gagging while trying to start or someone is shaking the vehicle. Took it back to ford and they could not recreate the miss or find any codes. Any idea? Possibly a coil failing? Is it coincidence that it’s now running rough or did they screw something up?

 

[Jay5.9L]

And yes I know that the cam timer will crap out sooner or later but I’d like to keep this one going for at least another year or two before replacing it.

 

[Herzog]

If you can get it to happen while sitting try pulling 1 coil at a time and starting it to see if it either gets worse or stays the same. If it stays the same you found the potential bad plug / coil. I had to do this on mine. I ended up having a bad coil one time and a bad plug another time.

It freaking sucks, but man I've gotten good at getting those stupid coils in and out.

 

[Jay5.9L]

I’m actually ok replacing all the packs since if one is going out the others will follow eventually. Only problem is that the aftermarket ones are 1/3 the cost but have a bad rep.

 

[Jay5.9L]

Could ford have put in a defective plug? It’s intermittent so I’m kinda doubting that assuming a plug is either good or bad

 

[Herzog]

Could ford have put in a defective plug? It’s intermittent so I’m kinda doubting that assuming a plug is either good or bad

I wouldn't be surprised. When I changed mine last, I used motorcraft plugs and there was a bad one in the bunch.

 

[Jay5.9L]

Wife has been driving it and the miss/shake happens on start up or idle as in a stop light or backing out of a parking spot

 

[rholbrook]

I know it sounds silly but have you disconnected the battery for a few minutes and give the computer a chance to reset? I had a 2011 Expedition that when it started running a little goofy or shifting weird, thats what the dealer said to do and it would actually fix it. They told me that the computer begins to learn how you drive and if you drive easy, it tends to mess with the computer and by disconnecting it, it can reset what it has learned.

 

[Herzog]

Wife has been driving it and the miss/shake happens on start up or idle as in a stop light or backing out of a parking spot

Ahhh, that's a whole different thing. I know what that is... it's the VCT Solenoid! It changes the timing of the the cam so you get better fuel mileage on the hwy. When they clog up, they stay in that position and cause it idle really bad at a stop.

You can try running some cleaner through with your next oil change to kick that can down the road but you'll probably have to end up replacing them. I think there is one on each side.

 

[Jay5.9L]

That sounds like it. I’ll have to try this out tomorrow

We got a oil change at the same time as the tune up. Could have they some how made the VCTs get weird?

 

[Trate D]

I would try to isolate what cylinder is doing it. Watch live data while it’s stumbling switch plug then coil with another cylinder to see if it chases the part. It possible you got a bad plug or it got dropped and cracked it. On those engines it’s common for people to just drop the plug into the head and close the gap.

Check oil level too. Those engines love clean, proper level, proper weight oil to run smooth.

 

[Herzog]

That sounds like it. I’ll have to try this out tomorrow

We got a oil change at the same time as the tune up. Could have they some how made the VCTs get weird?

It could, they also act up if your oil is low from what I've heard.

 

[TRD270]

I know it sounds silly but have you disconnected the battery for a few minutes and give the computer a chance to reset? I had a 2011 Expedition that when it started running a little goofy or shifting weird, thats what the dealer said to do and it would actually fix it. They told me that the computer begins to learn how you drive and if you drive easy, it tends to mess with the computer and by disconnecting it, it can reset what it has learned.

All the things I did to fix my misfire...... this seemed to have fixed mine before I got rid of it.

 

[Jay5.9L]

Disconnected the battery for 40 min, checked the oil, checked that the coils were seated. All looked good. Started fine and drove fine around the neighborhood and freeway.

This morning wife starts it and said it was still bad. Going to take to back to ford this weekend and have them look at it again. Possibly swap in all new plugs.

 

[rholbrook]

Damn

 

[4x4_Welder]

On my Explorer, several of the coil and injector connectors broke when I changed the intake. I also had this happen on a tune up on a 6.2. Replacement connectors are available fairly cheap, I went cheaper and used zip ties to hold it all together.

 

[Jay5.9L]

When the wife dropped it off today the service guy said “Oh yea I remember you. When I backed it out the first time it felt weird. And I saw you last week when you dropped it off.” So we got confirmation that they did something to it.

 

[Jay5.9L]

Update: Dropped it off at Ford in Draper Friday. Got a few texts with the service advisor saying it may be transmission related. Almost lost my sh*t and said it had to be ignition related due to the previous spark plug service. Long story short finally got it back today and it was the #3 coil.

 

[Herzog]

Update: Dropped it off at Ford in Draper Friday. Got a few texts with the service advisor saying it may be transmission related. Almost lost my sh*t and said it had to be ignition related due to the previous spark plug service. Long story short finally got it back today and it was the #3 coil.

Hilarious that us dorks on a forum can come closer to a solution than the dealer with all the equipment. Glad it's resolved!

 

[Jay5.9L]

Doesn’t bolster my faith in factory trained service lol