my 4.0l isn't running so well lately and i'm gonna start to put some $$ into it. First thing is first I need to do a major tune up. What do I need? Cmon guru's enlighten me

 

plugs
wires
air filter and an oil change
new o2's just the 2 upstreams
Clean the maf


Have you checked your codes?

 

X2 and iac, run some seafoam through it to. as well as a new fuel filter.

 

Pretty much the above is what I did when I needed a tune up

 

thanks guys, replaced plugs, wires, pcv valve and fuel filter. the truck is running much better now, huge difference!

 

thought so, np man.

 

What plugs did you use?

Not sure what the owner's manual specified in 93, but on our 98 the previous owner put in cheapo Bosch coppers, I replaced them with Autolite Platinums and wow, huge difference in smoothness and performance! Since this is a domestic, stick with the domestic brands for best performance, seems each continent has its own plug style and they dont always interchange very well lol.

 

best to use motorcraft its a oe replacement the best plugs to use on ford

 

FWIW, autolite makes motorcraft.

 

try this very easy 2 step process to get better gas mileage and more horse power than your 4.0

step 1-take your truck to the junk yard

step 2-buy one of these

 

wow did not know that lol thanks
Ford doesn't actually make the Motorcraft spark plugs, Autolite(owned by Honeywell) makes them. So buying OEM style Autolites is the same as buying Motorcraft spark plugs


Actually... Motocraft is a priviately owned company. They used to own Autolite, but sold it off in the 70's. Two different companies. I also verified this by calling Autolite and asking them. 1800-890-2075 ext 1 then ext 3. Also see

 

This isnt 100% true, Denso makes plugs for certain engines. (SHO for example) The Autolites and Desno for the gen 1 iirc sho, have different nose lengths.

 

This isnt 100% true, Denso makes plugs for certain engines. (SHO for example) The Autolites and Desno for the gen 1 iirc sho, have different nose lengths.

For the ranger it holds true.