02 3.9L LS troubleshoot

[Aqualung]

Hello all!
For years now I have used this forum to help me diagnose and solve my LS issues -and am sincerely thankful you guys have put so much information out there- but the time has come for me to finally make an account and ask for some input. Right now my 2002 3.9L Lincoln LS (180k mules) has a rough idle after it sits running for a few minutes. It will idle fine for 5 minutes or so then rpms drop from ~1k to ~500, engine almost stalls, then it idles weird, chugging a bit sounds like vroom-0.5 second-vroom-0.5second-vroom.... Checked and replaced most(I think) of my vacuum lines, rubber grommets that the 2 vacuum lines goon top of the engine(throttle body maybe?), plugs, couple coils, gas cap, and fuel & air filter. Had bank 1 bank 2 lean codes this week and misfire that are now gone but still idles weird (only after a few min sitting still). About a year ago I found my plugs covered in oil so I replaced both valve cover gaskets along with plugs, injectors, and coils which solved all my problems until now (seriously can’t thank everyone on this site enough). Now, car is running MUCH better except the idle issue. Upon further inspection noticed a hissing sound from the back of passenger side engine. I was poking around and just barely touched the left hose on the DPFE solenoid (AKA EGR pressure feedback sensor) and it snapped off. Where do the two hoses on the DPFE connect into the exhaust and are there any vacuum lines behind the engine I can’t see that could be the source of the hissing? Any other thoughts on my issue? Thanks!
-Luke

 

[Aqualung]

Also, I recently cleaned the MAF and I have not checked O2 sensors. I only replaced 3 vacuum hoses and the "new" ones came from the junk yard but they looked fine and fit much tighter. I inspected the larger diameter hoses and wrapped them entirely with electrical tape just in case, they feel decently tight where they connect.. I did not replace the hoses that go to the EGR though (the small hoses Part#
Xw4z-9e498-af).

Can anyone help point out what I might have missed?

Here is a picture of what vacuum lines I replaced:

 

[Aqualung]

And here is a picture of the plastic tube that I broke off (used some epoxy to put it back on for now). Found this picture on the internet but the arrow is pointing at the piece that broke off in the hose.

 

[joegr]

This makes it a lot easier to locate the exact source of the hissing.

www.amazon.com/gp/product/B0015DLMOO/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

 

[Aqualung]

This makes it a lot easier to locate the exact source of the hissing.

www.amazon.com/gp/product/B0015DLMOO/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

Thank you, I’ll pick some up and see what I can come up with.

Another thing, on my lunch break today I let my car idle until it started running rough. Turned off my car and unplugged the MAF sensor and started it back up, idled fine for ~10 minutes. Turned the car off and plugged MAF back in, started it up and it was running rough again, even completely stalled a few times which it’s never done before.

I can’t find it now but swear I remember reading somewhere that this is a good sign of something needing replaced. EGR maybe? Or should I replace the MAF?

 

[Aqualung]

Car dies while idling in park

Found it. I already replaced that hose yesterday though. Think I’ll order a new one of these:

 

[joegr]

... I remember reading somewhere that this is a good sign of ...

It's a good indication of unmetered air (intake air/vacuum leak) getting in. The hissing sound is also a great indication of the same.

 

[AmsterDutch]

And here is a picture of the plastic tube that I broke off (used some epoxy to put it back on for now). Found this picture on the internet but the arrow is pointing at the piece that broke off in the hose.

View attachment 828571220

Those two vacuum lines connect into the two metal vacuum lines a little below the EGR Pressure Feedback Sensor...do you have access to a decent code reader or you can run down to Auto Parts Store and have them hook up there’s to see what’s on the PCM for codes? O’ Reilly’s has a Westinghouse Propane Torch for like $25 you could always purchase this torch and run the Propane over the intake if you haven’t already and see if your idle changes at all ...

 

[AmsterDutch]

Car dies while idling in park

Found it. I already replaced that hose yesterday though. Think I’ll order a new one of these:

View attachment 828571221

Unless you purposely ask for a shop to smoke test the system all they will do is run some propane over your intake or spray some starter fluid on intake and $100 dollars later you will either have a yay or Nah ...$25 dollars is cheaper to buy torch and then you’ll always have a torch

 

[Aqualung]

Thank you all for your replies.

I think I figured it out!
The hose I said I already replaced (post #7), well the sound was coming from on the passenger side where the hose goes into the top of the intake manifold (Bottom picture, blue arrow). Apparently there is a plastic adapter that goes between the hose and the manifold. I’ll post a picture of it tomorrow but it’s about an inch long and plugs into the intake manifold on one side and the hose clip fits over the other side. The part that goes into the IM is loose and wont stay in place and when I push it tight the hissing is gone.



Any recommendations on what I should use to glue the adapter back in place so that the seal is tight?

I’m pretty excited right now, I feel like my search is over.

On another note, does anyone know the size of the bolt that goes in this hole? It looks like I’m missing one..

 

[joegr]

I think the bolt is M6 x 32MM

 

[Aqualung]

I think the bolt is M6 x 32MM

You were right thanks Joe.

 

[Aqualung]

Here are the pictures I was supposed to post of the adapter thing. I put a ring of jbweld marine putty around the lip and smushed it down into its hole.

 

[Aqualung]

And now for an update.

Car was running amazing after I replaced everything I mentioned in my previous post. Best gas mileage I’ve ever gotten, ~28hwy/~17city. That lasted about 3 days. Car started idling rough again and stalling out at stop lights and during slow turns coming from a stop. It’s my only car so I’ve been driving it despite the issues. Every day seems to be worse, now it sputters, misses, and rpms randomly spike while driving at speeds from 0-65mph.

Tonight I went through all of the vacuum lines again and everything looked fine. Scanned the car at O’Reilly and got the bank 1&2 lean codes along with an airbag disconnected code and an ABS hydraulic pump motor circuit failure code.

I feel like it’s got to be the COPs.. Same symptoms as before I replaced them last year- which fixed it. Unless my vacuum leak is at the intake manifold gaskets I find it hard to believe that I have a leak somewhere else.

There was quite a bit of rust on my bank 2 coil boots and plugs when I changed the plugs and the cylinder 8 coil (last week), but they were completely dry. I really don’t want to but do you guys think I should take the valve covers off and take a look?

Any thoughts?

 

[Aqualung]

Also, I put a towel over the air intake tube where it connects to the filter box and wedged a lit cigar between the towel and into the intake hole (where it disconnects right after the MAF). Let my car smoke the stogie for a good 10 minutes while I looked everywhere for smoke - didn’t see or smell smoke coming out of anywhere. Not sure if that’s the right way to do a smoke test though.

 

[Aqualung]

I’ve been researching possible issues all night and I am wondering if it could be my timing chain tensioners (FFS everything I read seems like it could be the problem). My car does have a loud clacking noise coming from the engine that should not be there. My car has ~185k miles and I’m sure they’re the originals.. any idea if my symptoms are similar to that of failing tensioners?

 

[joegr]

...There was quite a bit of rust on my bank 2 coil boots and plugs when I changed the plugs and the cylinder 8 coil (last week), but they were completely dry. ...

Your cowl seal around the passenger side wiper shaft has rotted out. You need to fix this before you ruin another set of coils. Ford sells a repair kit that is all of $5. Otherwise, you can get some stick on foam gasket from the hardware store.

 

[Aqualung]

Your cowl seal around the passenger side wiper shaft has rotted out. You need to fix this before you ruin another set of coils. Ford sells a repair kit that is all of $5. Otherwise, you can get some stick on foam gasket from the hardware store.

Thank you! I looked into this and it seems very likely. A post in another thread said that the gasket is above the drivers side coil bank. This makes sense because my cyl 8 coil was very rusty, cyl 7 -kind of rusty, cyl 6 -a little rusty. Should I take the valve cover off and take a look/clean it up?

Re&Re - Wiper Arm Shaft Cowl Seal

 

[Aqualung]

Here’s a video of my engine running. The knocking noise is pretty loud and there also seems to be a hissing noise. I held a hose to my ear and could hear a loud hissing noise when the other end was on/around the EGR valve.

 

[joegr]

If you are touching the hose to the body of the valve, then is could just be the his of the exhaust gas being sucked into the intake through the partially opened valve. Otherwise, the hard plastic vacuum tubes (like the green one to the EGR valve) are good suspects. They get brittle and can crack where you don't easily see it.

Hold the end of the hose against the top of the valve covers at the very front. Is the knocking sound much louder there than elsewhere? If so, it could be the chains slapping.

 

[Aqualung]

If you are touching the hose to the body of the valve, then is could just be the his of the exhaust gas being sucked into the intake through the partially opened valve. Otherwise, the hard plastic vacuum tubes (like the green one to the EGR valve) are good suspects. They get brittle and can crack where you don't easily see it.

Hold the end of the hose against the top of the valve covers at the very front. Is the knocking sound much louder there than elsewhere? If so, it could be the chains slapping.

When I hold the hose to the top of the valve covers at the front I can hear a slight clicking noise, it doesn’t seem like the source of the loud knocking though.

I poked the hose everywhere and found that it was very loud when placed on every single one of the injectors. I searched the forum and it seems like this is kind of common but it also seems like everyone had a different thing that fixed it. Some people said change oil filter, timing tensioners, idler pully, imrc.. list goes on. I also read somewhere that this sound could be cause by a cracked intake manifold which would maybe explain my banks 1&2 lean codes/vacuum leak?

I ordered the cowl seal, 8 new OEM coils, valve cover gaskets, egr gasket (why not, it was $0.75), and timing chains/tensioners -everything will be here saturday.

Meanwhile, I went to the yard tonight and pulled that cluster of small hard vacuum hoses (red,green,yellow) along with 3 COPs. Picked up 4 new plugs from autozone also. The vacuum hose was in great shape and mine pretty much fell apart when taking it off so I was optimistic -car still ran rough after replacing.

Wasn’t surprised considering I thought I had some bad coils so I pulled em all on bank 2. They all looked fine and my week old plugs still looked new. Swapped each of them with each of my new-used coils and car still ran rough after every change. I only put a new plug in cyl 8 though.

Went to bank 1, again everything looked great. Changed the coils around and added one of the new-used ones. Couldn’t test them because my intake was off. During this time I also did the following: made sure all plugs were gapped to 1mm(none were too far off), checked and pushed on every plastic connector I could find, loosened up ground wire and retightened, and scraped clean all of the brass parts on coil bolt holes and valve clover coil bolt holes (no clue if some sort of connection is made here).

After I put my intake on and it was idling and driving much better, still felt a slight hesitation a few times on my test drive probably due to a failing coil somewhere. The knocking noise has not changed at all though.

Sorry for a long post going over shit that’s mostly already been covered on this forum, Ive really tried to do as much research as possible before posting and I want to document everything so I can look back as I go.

Joe, I’m in Boise Idaho, if you’re around these parts I’ll totaly buy you a beer (or 6) as a thank you. I don’t have a lot of experience working on vehicles (until I bought a Lincoln LS) and it helps so much to have someone to troubleshoot with.

 

[Aqualung]

I made a short video comparing my engine to every video I could find where someone was having similar symptoms, most of which said it was a timing chain issue. I think I can hear a similarity in the rate at which the knocking occurs, but maybe I'm just telling myself that because i want a definitive answer and resolution to my problem...