Hey all, new Fit owner here and thus, first post on the forum...

Upon purchasing my manual '07 Sport (89,000 miles), I performed the following within the first 1,000 miles:

1. Oil Change
2. Air Filter
3. Cabin Air Filter
4. Spark Plugs

My first 4 fill ups averaged 32.7 MPG. That's mainly highway driving and up and down the hills at the foot of the Blue Ridge.

I replaced the plugs with the OEM NGK Laser Iridiums. A buddy who owned a Fit cautioned me about the softness of the aluminum head and not to over torque the plugs as he had stripped one of his. I have to admit that of all the cars' plugs I've changed, the Fit was the most uncertain. There's no "yep, that's tight" feeling to it. I didn't have a torque wrench handy, but 14 ft/lbs is not a lot.

That said, I started smelling gas in the cabin while sitting at idle. I pulled the plugs and sure enough, two cylinders were "loose" and there was soot on the boots. The plugs were also a bit sooty (see attachments).

I reinstalled them, tightened them down more (still without torque wrench), and drove a tank's worth like that (32.8MPG, so no change). I still smell gas, but not as much. The car isn't idling roughly or driving poorly. I'm going to pull them again today and check, clean, and reinstall.

Question: Could having the plug(s) loose foul them in any way? Should I replace those two plugs that were loose?

 

I agree that 14 LB/FT is too little and I think others here will agree. E3's website shows 18-22 LB/FT for 14mm plugs in an aluminum head and NGKs website shows 18-21.6 LB/FT for their plugs in an aluminum head. My Haynes Fit Manual shows 20 LB/FT. My Nissan Frontier with similarly sized plugs in an aluminum head requires 18 LB/FT.

Given the grief that loose spark plugs have brought to Fit owners, I suggest 20 LB/FT and using a torque wrench to be assured that all is correct.

 

Good to know, thanks.

 

Using mirror or camera INSPECT the plug gasket seat on the head!! clean it if dirty. (I used 5/8"OD rubber hose soaked in alcohol. when using new plug spin it in by hand (No ratchet) using 3/8" ID hose 7 inch long, then tighten the plug with 8 inch long ratchet; you will have to feel the sealing washer crushing. This washer is harder than on other plugs on different cars

 

Good tip! I always hand tighten without the ratchet (but, with the extension and socket).