Feedback from spark plug color

MMamdouh · Post by **MMamdouh** » Mon Apr 03, 2006 7:16 pm

Hi guys

we always look at our used spark plugs to get feedback on how our engines run... i took off mine but i got confused of what i found.

you all know that the normal burning deposits on a spurk plug is kinda brownish (like rust) or so... i didn't have that on my spark plugs so i knew i am not burning fuel correctly.

now for the tricky part, black deposits means rich mixtue and white deposits means leaqn mixture... i got both

cyl #1

cyl #2

cyl #4

P.S: cyl #3 spark plug was a bit hard to get off so i used WD 40 to loosen it... it came out covered with WD 40 so i got no feedback from it.

yep the bottom of the spark plug is a bit black but the electrods got white deposits so what does this mean? am i burning rich or lean? does this got to do with ther operating temp of the spark plug??

i know those are not the OEM spark plugs for the 1.5 SOHC lanos but they are the same temp rating as the OEM... i was running octane 92 for some 1000 kms before taking off the spark plugs, does this got anything to do with it??

MMamdouh

BosnianLanos · Post by **BosnianLanos** » Mon Apr 03, 2006 11:42 pm

I think your plugs look normal, they don't seem to exhibit any severe condition that would indicate running rich or lean. Besides, the air/fuel mixture is controlled by the ECU and if you've never done anything to it, then you shouldn't have any problems.

Does your car run like it is rich or lean?

JohnnyC · Post by **JohnnyC** » Mon Apr 03, 2006 11:46 pm

Oh NO! You're Woo is doomed!

You're going to need to replace everything... it's all over man... I'm so sorry.

haha

MMamdouh · Post by **MMamdouh** » Tue Apr 04, 2006 9:00 am

BosnianLanos wrote:Does your car run like it is rich or lean?

i am more inclined to think it is a bit rich... the exhaust smells rich and i got black deposits on the exhaust tip (more than it used to be in the past years) and i think it is because of my O2 sensor... it has done 74000 kms and 7.5 years so far so i guess it is tired or working.

MMamdouh

BosnianLanos · Post by **BosnianLanos** » Tue Apr 04, 2006 6:46 pm

Again, I don't think that the plugs are wildly out of their color range. However, if you want to be really sure, and effectively end all speculation forever about how the fuel system is doing, install an inline fuel pressure regulator, and tune it to the pressure you want until your car is happy.