New to forum: My explorer is a dog

[63hardtop]

Hello guys,

I have had my 98 eddie bauer v8 explorer for about a year now. I previously owned an 03 xls with a 4.? v6.
Im a huge 5.0 fan. i have one in my 63 ford falcon and have had numerous versions in other vehilces.
Anyway, my EB has 87,x.. miles on it... ive put about 5 to 6k on it since i bought it. ive noticed a progressive loss in performance over the last year. Both power and fuel mileage. I started out getting 15 mph regularly… maybe a touch less. My last half dozen tanks, I’ve been well under 13mpg. My driving habits haven’t changed, if anything, I’ve been more conservative. It may be that I have significant power loss and have had to compensate by giving it a little more gas. Hills that I used to climb without noticing, I now have to floor the pedal to maintain speed. It starts and idles and generally runs fine but is a dog when it comes to acceleration and power. It isn’t as powerful as I would like when it is running right, though acceptable to me… but its significantly less powerful now, and less efficient on fuel.
Ive thought about a cold air intake but read here that a good flat filter will do as much for power/mileage. The mac kit looks affordable? Does anyone know if the filter that comes with it is decent and cleanable/reusuable?
Obviously tune-up stuff like the plugs will be done.
I was wondering if maybe the cats could be clogged/bad and could be robbing power. I have to pass emissions annually here in CO so I don’t believe removing the cats completely is an option. Ive read there are two sets of cats on the explorer and im wondering if I could safely remove one set and still pass emissions.

Anyway I’m looking for opinions/tips etc on how to get the power and mileage back to where they were ….at least.
Any pointers?

Thanks a lot

 

[JCat]

I would recommend that you check your compression in each cylinder. . . Get a compression tester and learn how to use it. Whether you are buying a used vehicle or boat, this test is the best way to determine an engines health.
.
As for removing the cats . . . . take a good look under your Eddie Bauer, and then tell me how easy you think that might be to do.
.

 

[drbenz]

Make sure to put a new fuel filter on your tune up list as well. The basic cat condition can be checked cheaply with an inexpensive vacuum guage hooked to manifold vacuum. See what the hot idle vac reading is and compare it to the reading at about 3k rpm, it should be at least as high or higher, it will be lower if the exhaust is stopped up. It is likely that the problem is a dirty/defective air mass sensor lying to the computer about how much air is going in the engine (as I think about it check the air boot also for tears or loose clamps). Just for grins clean the mass air sensor with electric contact cleaner or brake cleaner and let it dry and disconnect the negative battery cable for ten minutes, that will clear the previous fuel trims then drive it and see if it makes any difference.

 

[63hardtop]

thanks,
i have a compression tester and i know how to use it. i dont recall the compression readings when i purchased the explorer but compression was good and even between the cylinders a year ago. i dont think my power loss issues are related to compression loss at this point.

its obviously a tangled mess of exhaust below these vehicles... but if the converters are bad and need to be replaced, its going to be difficult no matter what work is done. i didn't suggest removing or replacing them would be easy. considering the extreme cost of catalytic converters, i am simply curious if removing 2 of the 4 is and option for cost and performance reasons.

 

[63hardtop]

Make sure to put a new fuel filter on your tune up list as well. The basic cat condition can be checked cheaply with an inexpensive vacuum guage hooked to manifold vacuum. See what the hot idle vac reading is and compare it to the reading at about 3k rpm, it should be at least as high or higher, it will be lower if the exhaust is stopped up. It is likely that the problem is a dirty/defective air mass sensor lying to the computer about how much air is going in the engine (as I think about it check the air boot also for tears or loose clamps). Just for grins clean the mass air sensor with electric contact cleaner or brake cleaner and let it dry and disconnect the negative battery cable for ten minutes, that will clear the previous fuel trims then drive it and see if it makes any difference.

exactly the type of thing i was looking for. thank you. i have a lot of experience working on and building older vehicles (i currently have a 63 falcon, 66 f100 73 harley) but i am clueless about anything post mid 80's. i get it all in theory, just havent owned anything newer long enough to need to work on it. i have a vac gauge and will check it out. is the fuel filter in-tank?
thanks again.

 

[RomeovilleIL]

MAF is good advice even if not solely causing your issue, it can only make the truck run better.

Filter is in-line, just inside the frame under the drivers seat. Check your fuel pressure after changing the filter. If it is weak your truck will run very much as described.

 

[bobflood]

MAF is good advice even if not solely causing your issue, it can only make the truck run better.

But clean with MAF cleaner (available at most auto parts stores), not brake or carb cleaner.

Filter is in-line, just inside the frame under the drivers seat. Check your fuel pressure after changing the filter. If it is weak your truck will run very much as described.

You will need a special tool to take off fuel filter connections. Get the metal one rather than the plastic ones.