well my g/f is headed to TN and her truck has been getting crap for gas mileage i think its in need of a good tune up and it possibly has a vacuum leak.

i was wondering what do you all use for plus/wires/cap/coil? ive never messed with a 4.9L just wondering what the best to use is.

im assuming the old copper motorcraft plugs. a nice set of wires and a good coil and cap?

does the rotor normaly need to be replaced with the cap? the motor only has 120,000 suppositly

 

I either use Motorcraft or another name brand for the cap and rotor, motorcraft copper plugs, and Taylor low resistance spirial core wires. The cap, rotor, and plugs should be changed every 30k miles and have brass contacts. Avoid the real cheap sets. On both of my 300s I changed the wires to sprial core for the slight performance increase. Ignition wires should last a long time since they are on the cool side of the engine.
YMMV
rikard

 

thanks for the info will prob get a OEM cap or MSD depending on price. same with the coil. i might have a coil now that i think of it.

also is it hard to change the rotor? i have never done one before.

 

cheap way to gain some mpg but it takes a little know how and atleast 5 hours of down time

take the injectors out pull the caps orings and filters out and set them in chem dip and let set atleast 5 hours i let mine set over night then blow them off with the air hose dry them good and get the rebuild kits and put the new filters caps and orings i picked up 3 mpg with my 4.9 doing that but my injectors were bad

the chem dip is like $15 for a gallon can with the dunk basket inside
the rebuild kit was like $25 online i got the v8 rebuild so i had extra parts

a tip oil the oring b4 installing dont be afraid of lubing them

then do a good tune up cap rotor plugs wires air and fuel filter pcv valve oil filter

throw a timing light on it and check the timing for good mesure " the marks on the passenger side are the ones u reed off of they are hard to see but they r there

fatory ford motor craft parts are the best

also if i were doin all that id service the rear inspect the gears and fresh fluid

if auto id change the fuid and filter if manual just change the fluid if 4wd change the fuid in the tcase too

my truck around town is 16 mpg w/out over drive and i get close to 20 mpg at 50 mph constand w/out overdrive

 

The rotor just pulls off the distributer shaft. The Ford coils seem pretty good. My 95 and 94 still have the ones Ford installed and the 95 tested fine when I did my last tune up. Both trucks have over 200k. The 4.9 is one of the most reliable engines ever made and its easy to work on.
I use Berrymens B12 twice a year in each tank.
Regards
rikard

 

i know its the most reliable thats why i told her to get it. its getting 10MPG i think when the stock alt. caught fire it may have fried a vac line. she said it makes a bunch of noise at idle but not any when driving. also has a pretty bad exhuast leak i want to fix as well. No CEL.

prob do an oil change air filter. plugs wire cap and rotor and possibly a coil.

 

Don't forget a fuel filter.
My 4.9 has oversized tires and I only get 10 if I'm really beating on it or if it's locked in 4x4.
Jack up the front and see if there is any resistance in the wheel bearings or brakes and check the hubs to see if one of em is stuck or something. Turning the axle all the time will eat mpg.

 

its 2wd i hope the axle turns the whole time

i know its a vacum leak i heard it running the other day. im willing to bet some vac thing to the A.I.R pump

 

This might help you with understanding that system and how to replace the stupid plastic lines:
http://www.fullsizebronco.com/forum/...d.php?t=192382

 

Didn't know. Could still have brakes or wheel bearings hanging up if the vac line and tune up doesn't help.

 

Also its in the title of thread 92 F150 2wd 4.9l just givin ya a hard time

ill jack the front end up and spin um.

but i think a vac cap and some new plugs will help alot.

 

You people expect me to read a thread title or something?
For some reason my truck likes to eat plugs every 15-20k, probably because it burns some oil, but it could be all 4.9's idk. Throw a set in, they're cheap and check em after a couple oil changes.
If you are burnin oil you could benefit from a slightly hotter plug.

 

ya bout to go now. some compressed platt. plug is only .60 cents more each so im just gonna get those. maybe they will last longer. a set of motorcraft wires and a cap and rotor and a coil....and also some muffler weld for her nasty exhuast leak.

Very VERY dumb questions does this truck have an o2 sensor?

 

yup

 

Si senor. Uno numero.
I don't know if any of that was right haha, but yeah it has one precat.