kingrukus

On all nissan's and hondas, I always would put plugs in until they felt slightly snug, then added 1/4 turn. I suppose this rule doesn't apply to these 2v Fords eh?

cliffyk

Snug plus 1/16th turn for tapered seat plugs--this is from NGK installation guide (Section 2, click here)

Here's a link to a test I did a while back, an additional 1/4 turn requires over 45 lb-ft--I.e. WAY too tight:

kingrukus

What should I gap these plugs at?

kingrukus

They are the oem Motorcraft SP-493 plugs - I was hoping they would be pre-gapped.

cliffyk

0.054"

"Pre-gapped" plugs are a myth, any plug manufacturer will tell you so. Modern manufacturing techniques allow them to be made with consistent gaps, however that gap may or may not be the correct gap for your engine--I.e. you have to at least check it, and change it if necessary.

This is from NGK's website (click here)

"Since the gap size has a direct affect on the spark plug's tip temperature
and on the voltage necessary to ionize (light) the air/fuel mixture, careful attention is required. While it is a popular misconception that plugs are pre-gapped from the factory, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings (to ensure ignitability in these denser air/fuel mixtures). As a rule, the more power you are making, the smaller the gap you will need." [emphasis added]

kingrukus

I ended up checking all of my motorcraft OE plugs and many of them were way under 0.054"... anyhow I ended up adjusting them.

sfmustang

Question

On the passenger side, 2nd plug from the firewall its very hard to get to. There is the fuel rail I guess you would call it, but right at that 2nd plug from the back there is a T intersection from the rail to a connection piece that has a tube connected to it thats blocking access.

sfmustang

I found this online to show what i mean.

uberstang1

thats the fuel line to fuel rail connecion, the safetly clip comes off and theres a tool u insert to release the spring lock and then the line seperates from the rail. u should be able to change the plugs without removing any of the fuel stuff.

cliffyk

I have an '03, identical under the hood to your '04--and have never found it necessary to break the fuel line to change that plug (which I have done at least a dozen times).

What "weapons" are you using? I use an extended deep 3/8" plug socket and a 10" wobble extension:



Using an extended socket makes it much easier as it will not cant or **** on the plug.

wobble extension: