My last hope on my rough idle

[Billme]

That's ominous, how would I confirm it?

In my case, something was giving my ICV a command, but also the engine seemed smelly, kinda weird but not as smooth as it should be.. The MAS, fuel trims seemed off.
Like you, I changed every single item, expecting good change..
Another clue was the idle was different most of the time by switching the key off, and restarting..
Anyway, Hamfisted suggested Flagahip1, and the price was right.. Got it changed out, and the difference was incredible..
I don’t think it has ever run this smooth, and so far, everything is holding up great..
Everything is a roll of the dice since a lot of symptoms share the same problem..

 

[02Sexpedition]

You could have some wiring damage causing misfire. Especially if it’s in the main harness. You said it was rebuilt. With the amount you claim has been done, it can only boil down to a bad rebuild, wiring, or a computer issue.

 

[JustAnotherExped]

Hello everyone, as the title states this forum is my last resort before I fork over the cash to a real mechanic.

(video link at the bottom if you care to see it)

First, the issue - the vehicle has a rough idle that gets worse as the weather cools, (the engine temp doesn't affect it) at its worst it shakes the cab and has even stalled out at a light (once in 20,000 miles) in high temps it runs almost normally.


Some info on the vehicle and some of what I’ve done so far.


2000 ford expedition Eddie Bauer 5.4 triton 2 valve awd - 4wd


Codes 171 174 and P0300 the random misfire is only if I let it idle for a while, the lean codes are always there if I’ve driven a bit or idled a while

189,000 miles

fairly small hole in muffler

Engine rebuild at roughly 110,000 miles i’ve seen the receipts and I don’t think the last guy was smart enough to fake them…. Not entirely sure what was done in this rebuild though so take it with about a pound of salt.

Fuel pump at 111,000 according to the grease pencil under the hood

New MAF

Smoke tested for vacuum leaks found some (PCV elbow) , fixed slight improvement

Cleaned original AIC valve with no affect then replaced it with a motor craft one - small improvement in idle.

New battery, not sure if this could have an effect but still

New fuel filter

liquid moly engine oil flush

Injector cleaners of all sorts

Spark plugs

Ignition coils

Replaced faulty upstream passenger side o2 sensor

Regular 3000 miles oil changes with various high end 5w 30 synthetics for the last 20,000 miles Passenger side exhaust manifold gasket

IAT sensor

Air filter

Pulled and cleaned sediment from fuel tank, (learned that a light bulb is an effective redneck fuel float.

AAT sensor

New Napa metal PCV valve

Removed and cleaned entire throttle body.

A few new vacuum lines that were cracked.


Since doing all this I’ve done multiple smoke, water and propane tests looking for vacuum leaks but I’ve found nothing.

I'm attaching a two minute video showing the tac and some live data, as far as I can tell its only really bad in open loop, in closed it appears to be able to compensate, under load the trims improve some but at best it is still adding about 7% on both banks. it only seems to switch to CL if I rev it a few times.

Note on the video - I rev it at the beginning and then I don't touch the gas, brake, ac or anything else for the remainder of the video.

Link to the aforementioned video on YouTube because the quality drops when I post it here.

https://www.youtube.com/watch?v=zG9NPIIJcw0

I really appreciate any help, thank you.

I have had a cam follower spit out and therefore had a lean misfire with chuggy idle and poor fuel economy and power. I have also seen a random misfire when a new set of plugs was installed and a difficult to reach one got a small crack during installation.

 

[Gumbyalso]

I have a 2000 EB 5.4 4WD since new. It has 378K on it now. Around 200K I chased a vacuum leak for many months doing more than a bit of unnecessary diagnosis by replacement. I finally took it to the dealer. It turned out to be a crack in the intake manifold near the firewall that I would have never found. I paid them to replace the manifold and have never had a vacuum leak since. Your issue sounds very much like mine. They may not have replaced the intake manifold in the rebuild and only replaced the gaskets. The redesigned Ford intake manifold is superior to the original. Other than that intake manifold I have only replaced wear items on that engine (plugs, COPs, PCVs, etc). It has never been rebuilt. I change the oil every 5K with full synthetic and have been using Lucas Engine Oil Stop Leak since around 210K. Engine rattling when cold disappeared with the Lucas and never returned.

 

[danimerciss22]

When you have done all that, with slight changes, you need to consider it..I just went through something similar..

jiofi.local.html tplinklogin​

 

[1955moose]

Hello everyone, as the title states this forum is my last resort before I fork over the cash to a real mechanic.

(video link at the bottom if you care to see it)

First, the issue - the vehicle has a rough idle that gets worse as the weather cools, (the engine temp doesn't affect it) at its worst it shakes the cab and has even stalled out at a light (once in 20,000 miles) in high temps it runs almost normally.


Some info on the vehicle and some of what I’ve done so far.


2000 ford expedition Eddie Bauer 5.4 triton 2 valve awd - 4wd


Codes 171 174 and P0300 the random misfire is only if I let it idle for a while, the lean codes are always there if I’ve driven a bit or idled a while

189,000 miles

fairly small hole in muffler

Engine rebuild at roughly 110,000 miles i’ve seen the receipts and I don’t think the last guy was smart enough to fake them…. Not entirely sure what was done in this rebuild though so take it with about a pound of salt.

Fuel pump at 111,000 according to the grease pencil under the hood

New MAF

Smoke tested for vacuum leaks found some (PCV elbow) , fixed slight improvement

Cleaned original AIC valve with no affect then replaced it with a motor craft one - small improvement in idle.

New battery, not sure if this could have an effect but still

New fuel filter

liquid moly engine oil flush

Injector cleaners of all sorts

Spark plugs

Ignition coils

Replaced faulty upstream passenger side o2 sensor

Regular 3000 miles oil changes with various high end 5w 30 synthetics for the last 20,000 miles Passenger side exhaust manifold gasket

IAT sensor

Air filter

Pulled and cleaned sediment from fuel tank, (learned that a light bulb is an effective redneck fuel float.

AAT sensor

New Napa metal PCV valve

Removed and cleaned entire throttle body.

A few new vacuum lines that were cracked.


Since doing all this I’ve done multiple smoke, water and propane tests looking for vacuum leaks but I’ve found nothing.

I'm attaching a two minute video showing the tac and some live data, as far as I can tell its only really bad in open loop, in closed it appears to be able to compensate, under load the trims improve some but at best it is still adding about 7% on both banks. it only seems to switch to CL if I rev it a few times.

Note on the video - I rev it at the beginning and then I don't touch the gas, brake, ac or anything else for the remainder of the video.

Link to the aforementioned video on YouTube because the quality drops when I post it here.

https://www.youtube.com/watch?v=zG9NPIIJcw0

I really appreciate any help, thank you.

Well here goes my 2 cents. I have same SUV, same year. Your lean condition is saying #2 cylinder is lean. That and if you haven't already, fix that hole in muffler. All vehicles have to have a totally sound exhaust. It's not like old days before computers. Also, I'd check #2 fuel injector for power/ground. If good, pop in a known good injector, preferably a new one. Sorry if I missed anything. I'm assuming you did a compression test on at least that cylinder.