Dr.Le

I read 5 "How to" articles for changing spark plugs on a 99-04 v6 and i need some clarification.

3 article is straight forward: pull the wire, old plug out, new plug in, wire in.

simple, have done that all my life.

Now the other 2 article states that this model stang is "gas pressure" so i have to disconnect the fuel pressure switch in the back of the trunk.

so what is the CORRECT procedure for this tune up?

thanks...

my wires looks pretty new and i didnt see any arc at night; not gonna be changing them then.... i will check their resistance to see if its in specs. (<10k ohms/ft)

95beaststang

You don't have to touch the fuel system to change spark plugs .....

mustangmike09

thats funny ! where you read this non sense ?

JeffBall

Ive never heard anything about disconnecting the fuel pressure on any car to change the spark plugs...Unless its some Porsche or something lol

stangant

step one: unplug wires but remember or write what goes were...

step two: unscrew plugs

step three: screw in new plugs

step four: plug in wires

Daehawk

One at a time and not 2 or more at a time and you'll be fine.

Dr.Le

yeah, thats what i thought too... (no fuel involvement).

here's the link where i found the "odd ball" instruction. its pretty reputable too.

http://www.allfordmustangs.com/Detailed/2005.shtml

Step 1: The Mustang's fuel system is a pressurized system and before you do any work on the fuel system you have to release the pressure on the system. The way this is done is in the trunk there is a switch called an inertia switch. A wire needs to be unplugged from the bottom of the inertia switch. This will shut off the fuel pump. Please refer to picture 1.

Dr.Le

I also saw a video on youtube and ppl did the same thing by releasing the fuel pressure... but it was on a gt. I'm assuming GT requires this extra step huh?

NeoTokyo

Psst, hey.... Thats a GT, a 4.6L SOHC, the fuel rail DOES need to come off to change plugs or COP's.

That is an awesome write up, its just for a different motor than yours. The plugs arent located on the southern side of the head, they are located on the northern side of the head just under the fuel rail.

Its ok, people make mistakes but just dont call someone elses very hard work "odd ball."


Changing our plugs are very straight forward, remove whats in the way, do the plugs one by one and put things back. Pretty simple.

Jeff Hooper

I have 2004 3.9 ltr with only 80K miles on it! I love the car, however I have given up on the battle to change the spark plugs - I now hire people to do that. They are almost impossible to reach!!!