Spark plug analysis

[Legacy777]

Well I changed plugs last friday. I did so mainly because I took my Torque 2 chip out, which was making the car run piggy piggy rich. anyway when taking the plugs out, I was curious as to how they were going to look.

There were a couple interesting things to note about the plugs.

A common thing with all the plugs were that the porcelin behind the electrode was not white, but was black/carbonish color. How large an area this black was at varied between plug. I'm not sure why this was like this

Other thing I noticed was the porcelin that was still white on some of the plugs had a yellow and sometimes pinkish hue to them.

I don't think my car is running tip-top, I know I need to do some injector work, and possibly have an intake manifold leak, which I have all the parts to swap in, just need the time.

But other thing I'm not sure about would be carbon build-up, due to the age and mileage of my car.

Anyone have any comments on the spark plug attributes?

I'll try and get some pics of the plugs tonight.

[SubaruCO]

Josh, I'm running the same engine with 120k miles. I use the NGK V-Power plugs and last time I checked them (during a compression test) they had just a very light tan color to them. All cylinders are the same color. I have a few engine mods (more suspension mods than anything else) and I consider my 2.2 to be a solid performer and in tight condition. Maintence is regular with top fluids and i have run toluene during a couple of stressful rally-x's (probably cleans out those injectors). So, finally, my opinion would be that you are indeed running a bit rich. Depending on how long you have been using the torque chip this isn't really suprising. I'd change the plugs, run w/o the chip for a couple of months, then run a compression check and look at the plugs. If everything checks out then no problem. If you wanted to run the chip all the time then switch to a hotter plug to keep the carbon buildup down.

[vrg3]

How long had those plugs been in there?

A common thing with all the plugs were that the porcelin behind the electrode was not white, but was black/carbonish color. How large an area this black was at varied between plug. I'm not sure why this was like this.

What do you mean by "behind?"

Other thing I noticed was the porcelin that was still white on some of the plugs had a yellow and sometimes pinkish hue to them.

Huh... I don't know about pinkish, but I thought yellow deposits were usually due to lead. You put unleaded in your car, though, so it must be something else.

But other thing I'm not sure about would be carbon build-up, due to the age and mileage of my car.

Well, running rich would cause more carbon to build up, I think.

The pictures would help a lot.

[Legacy777]

I'll take pics. That should help clear things up.

They look fairly normal other then the things I mentioned.....but let me get pics....

[Legacy777]

Ok, here's pics

http://main.experiencetherave.com:8080/ ... P_2222.JPG
http://main.experiencetherave.com:8080/ ... P_2224.JPG
http://main.experiencetherave.com:8080/ ... P_2225.JPG
http://main.experiencetherave.com:8080/ ... P_2226.JPG
http://main.experiencetherave.com:8080/ ... P_2227.JPG
http://main.experiencetherave.com:8080/ ... P_2228.JPG
http://main.experiencetherave.com:8080/ ... P_2229.JPG