white spark plugs!

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Mar 14, 2007 | 05:37 PM

428fourby

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white spark plugs!

I changed the plugs last night in my 95,351 and they look to be burning really lean. It is -20c but the computer should compensate shouldn't it?
Or is it normal in these engines to run lean? (they are pretty white though)
Thanks

Mar 14, 2007 | 06:48 PM

Trevor1

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From: Louisiana

White plugs are normal, it shows your engine is burning all the fuel, don't worry.

Mar 14, 2007 | 08:12 PM

mrl390

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From: Venetia, PA

White plugs are NOT normal. Plugs should be a golden brown like a marshmellow. White means lean and by the way you describe them it sounds like you are running way to lean. Check/replace your O2 sensor(s), check your fuel pressure. Is your truck running rough or losing power? You could also have a problem with your coil and your not getting hot enough spark. It could be a number of things. Any more input from others?

Mar 14, 2007 | 08:54 PM

428fourby

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The truck seems to run fine, and power seems ok ,mind you i've only had the truck a couple weeks so i don't know if it lost power.

Mar 14, 2007 | 09:33 PM

Calf_roper_John

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well, start with the basics..

Fuel filter, plugs, wires, cap and buttion, and a oil change. Check to make sure your coil is producing enough spark... (hook a plug and wire stright to the coil, turn the key, and the arc should be a baby blue color or use a volt meter). Adjust your timing to spec and use the recomended 88 octain or higher on the 5.8L(351)! Also check your fuel pressure.

From there go to other things, such as o2 sensors, ignition control modual, etc, etc.

It could really be a number of things, but this gives you a good starting place.

Mar 14, 2007 | 10:21 PM

MRL123

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From: Wetaskiwin, Alberta

Just my .02 on this thread. White plugs are not necessarily a bad sign - like anything else it depends on exactly how white they are. I'm not disagreeing with MRL390 on this. It's just that in my experience, even with my current F150, the plugs tend to be more white than the optimal golden brown color. This also applies to my Buick which sees 150 miles a day in my commute to work and back. My F150 runs like a dream and is pretty spot on in respect to trim and tune. I don't know if the headers would have an impact on the plugs and it seems to me that the plugs were fairly light even before I installed the headers. Maybe it's just the fuel that I run in my rides. The plugs on my motor bike are also more light white than tan or brown.

FWIW I'd probably throw a good tune up at it if it's been a while since the last one. Swap out the O2 sensor if the current one has over 50,000 on it and then run the beast for a while on the highway. Pull the plugs, take some digital photos and post them where we can see the plugs. We'll go from there.

Cheers!

Mike

Mar 14, 2007 | 10:32 PM

428fourby

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I've done most of the tune up other than the fuel filter and O2 sensor, which I will hopfully do tomorow night. I'll try and post some pics if I can figure out how!

Thanks