changed plugs now i have a problem

[mustangrfast88]

ok guys i need some help or some info. i got a 2000 expedition with the 5.4. i changed the plugs a few weekends ago and i ran fine no problems. well my wife has bewen driving it more then i have but yesterday we took a road trip. we filled the truck up before we left and i noticed this little ticking noise when i accelerate it sounds like a exhaust leak and i also noticed it is drinking the gas alot faster then it should be i mean i used to get 100 miles to a 1/4 of a tank and yesterday it got like 55 miles to the 1/4 of a tank. so what do you guys think it could be that is making that big of change in my milage

 

[JUST4FUN]

make sure you did'nt accidently disconnect any vacuume lines

 

[Mike214]

Possible ignition short to ground. Some ignitions sparking to ground can be quite loud. Normally though this would mean the plug was not firing and would produce a code followed by check engine light. Also a plug being loose or (knock on wood) cross threaded could priduce similar air rushing sounds, loss of performance. Id start by going back through the job again looking for anything odd.

 

[pronstar]

Spark-plug blowout, somewhat of a problem on the 5.4, is often preceded by a ticking sound.

I'd start by making sure your plugs are still torqued correctly.

Plug blowout is a PITA.

 

[mustangrfast88]

thanks guys for the input i will have to go back and look over the work but i dont have and loss of perfomance as in accleration it is just a drop in fuel milage and a big one at that. another thing is i got no check engine light either thats what is throwing me off so i dont know but i will have to go back and check it all again

 

[JUST4FUN]

has the gas co. changed to winter blend yet?

 

[mustangrfast88]

i think they have been changing over the last 2 weeks and what is the differance in the summer blend and the winter blend and will that cause a change in fuel milage

 

[JUST4FUN]

something to do with emissions ,and yes winter blend has less BTU's so less mpgs

 

[mustangrfast88]

i see well i guess i will just add some octane boost to the gas in the winter and i am sure thats what it is was the change in the fuel but man it was a big change

 

[JUST4FUN]

dont waste your money on octain boost a stock truck runs off of 87 any thing higher is only draining your pocket book .
if you want to do somthing find a shop that cleans injectors
and get them cleaned . fuel that is atomized better burns more completly more power and better mpg