devins97flareside

May not be in the right place for this, didnt find much help on the expedition forum. But I figured I'd ask you guys.

I bought an 03 eddie bauer expedition a few months back and it ran like crap. It has the 5.4 and it has 165700 on it. It had 160k when I got it. I put plugs, coils, injector rings, thermostat, crank sensor, IAC valve, EGR, DPFE, EGR solenoid, fuel filter, new coolant, changed oil with a motorcraft filter and full synthetic valvoline and I replaced alot the vacuum lines. All of it helped out alot. Before I was getting about 6mpg and now I'm getting about 10 and this is while the weather is below 35°. After I did all the work to it, (I'm guessing the cats) i heard alot of rattling in the exhaust, my Dad decided to floor it in park and the sound went away. Since then it has been running better and idles at about 650 rpm but has a vibration that goes away at 1000rpm and the exhaust has a gurgling sound to it. I have a video of it running (engine bay video) and I have a video of how the exhaust sounds (video of tail pipe) but it wont let me upload them. Anyone had this problem? I'm about ready to take the down stream cats off and put a new muffler on. No there is no emission testing here. My f150 has no downstream cats or muffler, didnt suffer any fuel mileage and it doesnt throw a code. Any help would be greatly appreciated!

DarrinT04

the muffler is probably where the sound is coming from. i had a rattle in my exhaust a few years ago. i replaced the muffler and the sound never came back. never heard a gurgle though. you should replace the muffler, i don't think it's coming from the cats

Jbrew

NM lol.

Livernois Motorsports

I also have a 5.4L Expedition for a winter beater and wish it would get better gas mileage. I did a tune up and the usual maintenance items and found out there was an exhaust leak at the manifolds. Then doing more research I've found that these 5.4L Trucks and SUVs are notorious for exhaust manifold leaks that can cause the exhaust to sound different and of course doesn't help the MPG either. So I would suggest to check the manifolds if you didn't already to make sure they are not cracked or leaking.

DarrinT04

the exhaust manifold leak is common with the triton engines. once the leak gets bad enough it will create a ticking sound from the exhaust. i hear it on f150's all the time around here. .

devins97flareside

Well I figured one of the issues out, it is now getting roughly 13mpg, going 70mph. Put its 4th thermostat in it 2 of them were Murray and the last 2 were motorcraft. I checked over the manifolds, had that issue with my f150 and ended up putting shorties on it, but the manifolds on my expedition are in good shape yet, no broken studs and no cracks. I will try out the muffler next before I end up gutting it removing the down stream cats. Also, today I noticed that the exhaust has a fuel/sulfur smell to it. Not so much fuel but more sulfur. I'm not sure if I mentioned, but it does have the p0403 code which is the "egr circuit malfunction" and it has a vibration at idle, not a misfire vibration, more-so like a bad motor mount but. Brought it to my local Ford garage on 1/24/19 and they inspected it. Told me that the egr solenoid needed to be replaced and that's what was causing it, well it's a brand new OEM solenoid. I'm at a total loss. 😖

JCR 56

If you have a rattle inside the exhaust, it's more than likely the media inside one or more of the cats has came loose.