Sorry for the long post, but I have some issues with truck and I was looking to get some insight from experienced owners. Quick backround on the truck; it is a 98 expedition xlt 4x4 with 5.4, LLS suspension, 17" wheels and the 3.73 limited slip rear-end. It also has a K&N filterchager and a borla cat back exhaust. The truck has 117K on the clock.

1) I have an awful rattle coming from the rear suspension that I can't find. I put in a pair of Bilstien rear shocks about 2 years ago and I just put in an energy suspension sway bar kit. The rattle is still there and getting worse in cold weather. Anyone else expereince this problem?

2) Over the last 6 months I have noticed a drop in power and MPG, I was wondering if it is worth changing teh O2 sensors even though I haven't got a check engine light yet. I scope it with one of those cheap scanners from Pep boys but it didn't return any codes. Anyone seen a significant improvment when changing these. I was also thinking about changing the plugs again (changed at 62K) the truck now has 117K miles.

3) My right heated mirror isn't working anymore (left is fine), are there separate fuses/relays for each mirror or are they on the same curcuit?

I appolgize for the long post, but all this stuff has been nagging at me for awhile.

Thanks for any help you can give.
Eric

 

Ericg70, welcome to FTE. Personally I can't help you but I am replying to give your post a BUMP back to the top.

Someone will be able to help you out, I'm sure of it.

 

check the rear sway bar links that connect the sway bar to the frame,have seen them get worn and cause a rattle.as for the lose of power i would start with a fuel filter.a restricted filter will cause a fuel volume lose but the pressure stay in specs.also clean the mass air flow sensor. the k&n filters have oil on them that will film over the fine wires in the sensor and give the computer a bad reading.as for the mirror i dont have a answer.check in the owners manual for the fuses.good luck

 

David thanks for the bump.

I-m tech, thanks for the insight I will check the links and start with fuel and MAF. Thanks again

 

Hey guys, what is the best way to clean the MAF sensor, should I just use a rag or can I use a cleaner like a carburetor cleaner?

 

if you just replaced the plugs and not the wires, try doing both...wires degrade. I was pleasantly surprised at the improvement I got with plugs, wires and power injector flush at 100,000 miles. Big improvment in power and smoothness.....I felt like I was driving a new truck.

 

I would avoid using carbuerator cleaner, they tend to be a bit harsh. You may see some drying and maybe some cracking if you do.

This is a little off point but I was once sprayed right in the eyes with carbeurator cleaner. It had to do with alcohol and matches . . . anyway I got to play with their emotions afterward pretending to be blind. Sorry it just popped in my head.