5.0 Rough Idle issues

[Strokerswild]

My '19 F150 with the 5.0 has done this since Day 1, and it drives me nuts.

It only happens at idle with the engine fully warmed up. One of my thoughts is that hot idle oil pressure may be low enough that the cam phasers are having trouble keeping things under control. The other suspicion, coupled with the oil pressure thing, is that the DI pump might provide just enough resistance to cam rotation on that side that it keeps the phasers from keeping the cams, and consequently idle, in check.

Then again, I might be completely insane. But my '15 Mustang always idles like glass when hot, and the truck does not; for a second or two it's like the thing is a radically cammed pushrod engine.

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[silverbullet85]

How long has it been since your last oil change? Alex from Lund has talked about this issue on his podcast/YouTube show, he says it has something to do with the oil that when it's been awhile his own personal 19gt would do this and then after a oil change it would go away for a few thousand miles. My personal 19 gt has never done this but I change the oil often and every oil change I throw in a bottle of ceretec

 

[Gnatsum21]

Mine is a '15, same issue. Turned out to be bad gas. I bought a large can of seafoam and a Shell 93 octane fill up. A few floor board runs that night on an open interstate cleared it up.

Good old Seafoam!

 

[carguy231]

My car only does this on cold start and at the first red light. The rest of the time it is fine. Replaced TB, MAF, reloaded tune, etc. No joy.

 

[The RedMus]

i have same issues, i was worried about it but now i know that i am not the only one! it is randomly and only on sport mode after a few WOT runs, i was thinking on tune issues, so i went to re-tune and nothing to blame that behavior, not sure about the Gas theory or car will not running well all times and this engine moves very strong (470whp). i guess it is a bug on ECU or some miss-data. but how to figure it out!

Pdta: i have GEN 3 Coyote with 10speed Trans, full bolt-ons, Long header, catless, 2nd o2 sensor deleted, CAI and 93oct tune only, never used with E85.

 

[Strokerswild]

It would be interesting to see a log of when this occurs, assuming you could capture it.

However, my truck seems to be doing it more often then it did when it was new, so catching it would be easier....

 

[Strokerswild]

....aaaand BAM - yesterday my truck almost stalled at a light and the MIL came on.

FYI, code was P0021 (Intake Camshaft Position Timing Over-Advanced Bank 2). I reset and all was well this morning. I'm hoping for no reoccurrence, but I know better. At least I made it 17K miles before an issue (that's sarcasm, by the way), so much for this truck being as reliable as my last.

 

[Toretto]

I had a similar issue when I picked up my '21 GT back in July.....2 trips to the dealership resolved nothing, so I took it upon myself to do more research and ended up doing a KAM reset beginning of August and so far so good. This is what I did:

- Disconnect battery cables
- Connect Positive and Negative cables together (you can use Y clips or in my case, jumper cables) and let that sit for 15 mins to fully discharge the module capacitor (make sure you keep this away from any metal, etc.)
- Reconnect cables to battery, lock the car and walk away with your keys for 15 mins so the car can go into full sleep cycle
- After that, start the car and idle for 5 mins, revving it every 30 seconds
- Drive the car for 15 mins slow at first and then faster (basically, drive it at different intervals)

The idea behind a KAM reset is that, from what I was told, is that sometimes cars learn poor idling strategy while the car is in transit from the plant to various stops before finally arriving at your dealership.

Hope this helps.

Eric

 

[Strokerswild]

I had a similar issue when I picked up my '21 GT back in July.....2 trips to the dealership resolved nothing, so I took it upon myself to do more research and ended up doing a KAM reset beginning of August and so far so good. This is what I did:

- Disconnect battery cables
- Connect Positive and Negative cables together (you can use Y clips or in my case, jumper cables) and let that sit for 15 mins to fully discharge the module capacitor (make sure you keep this away from any metal, etc.)
- Reconnect cables to battery, lock the car and walk away with your keys for 15 mins so the car can go into full sleep cycle
- After that, start the car and idle for 5 mins, revving it every 30 seconds
- Drive the car for 15 mins slow at first and then faster (basically, drive it at different intervals)

The idea behind a KAM reset is that, from what I was told, is that sometimes cars learn poor idling strategy while the car is in transit from the plant to various stops before finally arriving at your dealership.

Hope this helps.

Eric

I had some time to kill and wasn't driving the truck anyway, so I did a KAM reset over the weekend. It seems to have worked, at least for now. The truck would sometimes struggle to maintain 500 RPM at hot idle in gear before, now it's probably ~600 and rock steady. Transmission shifting seems to have improved as well.

 

[Toretto]

I had some time to kill and wasn't driving the truck anyway, so I did a KAM reset over the weekend. It seems to have worked, at least for now. The truck would sometimes struggle to maintain 500 RPM at hot idle in gear before, now it's probably ~600 and rock steady. Transmission shifting seems to have improved as well.

Awesome dude keep monitoring it and see what happens....I was frustrated with 2-3 trips to the dealerships with nothing accomplished, so took matters in my own hands and found this.

 

[Dana Pants]

I did a bunch of data logging and the rough idle was so dumb. Throttle plate closes, car runs rough. I cleaned the throttle body and the problem got much better afterwards.

 

[Ayee__Jay]

i have same issues, i was worried about it but now i know that i am not the only one! it is randomly and only on sport mode after a few WOT runs, i was thinking on tune issues, so i went to re-tune and nothing to blame that behavior, not sure about the Gas theory or car will not running well all times and this engine moves very strong (470whp). i guess it is a bug on ECU or some miss-data. but how to figure it out!

Pdta: i have GEN 3 Coyote with 10speed Trans, full bolt-ons, Long header, catless, 2nd o2 sensor deleted, CAI and 93oct tune only, never used with E85.

FINALLY someone has the exact issues I have, mine first started with just mainly in sports mode but it's gotten to the point where it will do it randomly after a good 10-15 minutes of driving at a red light. Stalled on me once and when I took it to the dealership they replaced ONE of four vct solenoids which seemed to correct the problem for 2 weeks and it came back. I can't find the problem but its making the car less enjoyable to drive as Im scared i'll be sitting at a light and end up stuck.

 

[Strokerswild]

FYI, my F150 is back to its old tricks. Has to be cam phasers.

Much of what I've uncovered online says cam phaser issues can be caused by going too long between oil changes. To that I say BS, since my truck has had an intermittent miss at hot idle since new, and oil is changed at every 5,000 miles (currently at ~2,500).

I still wonder if it's a case of inadequate oil pressure at idle to keep proper phaser operation. At any rate, my truck will be headed in sooner or later.

 

[Bullit69]

My GT was doing this, I changed the spark plugs good as new !
change the plug gents!

 

[Strokerswild]

My GT was doing this, I changed the spark plugs good as new !
change the plug gents!

Might work for some, I've already thrown a code for an intake cam over advanced....

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