Hondata

I changed my sparks plugs today, sadly i was not careful at wich is wich (mabe cylinder 3 was the correct looking light brown color)

ok, happy to put new ones, but wondering if tuning is that bad giving plugs such a disgusting aspect.

Along with changing the plugs I installed an oil catch tank, because revving higher made me use oil, and the oil catch will make me view if the oil goes where it should. (this may also help remove contamination from the air intake) - I've used a little less than 1L of oil in 10 000 km.

those Denso IK 22 have been used for 50 000 km / 2 years. (same plugs was stock, then changed camshaft, then tuned, etc... )
i was not expecting that difference between plugs !!
please also note that most of those 50 000 km were with EGR "on" ans I plan also on removing that (i've tested and tuned for egr off rescently)

QUESTION : when can I remove the new plugs to "read" them ?

is there a specific procedure before turning off the engine to read plugs ?

if I see some black deposit, how much should I lean that cylinder ?? or was it oil ?
if I see some white deposit, how much should I increase fuel in that cylinder ??

Obviously the car ran rich for a long time because of noisy cams made it retard and richen before i find right K.sensitivity. But i fear it's not the only point.

I'm surprised it ran. I suggest doing a leakdown to determine if the carbon is from oil or fuel.

Given the variance over the plugs, I'd also do an injector flow test. Sometimes one injector has less flow, which results in 3 rich cylinders and one lean cylinder since the o2 is averaged over all 4 cylinders. However, none of them look lean.

If there is a problem you'll see carbon in the plugs after a single driving cycle.

The car runs fine, sound good, no smoke, temperature stable, pulls better than my wife's stock one from 2k to 7k.

no difference before/after changing the plugs.

i will check the plugs soon, will post picture and careful about order, 1, 2, 3, 4 this time.

leaking valve or poor injector...

the only clue i have for the moment is that oil is used (1L for 10 000 km), faster than before we did the camshaft/springs.

if I don't see the oil go in the can, then that would be a problem.

please elaborate "leakdown" what is it ? look for a leak ?

1 l per 10000 km or 1 l per 1000 km?

A leakdown tester will tell you if the rings or valves are sealing effectively.

http://www.amazon.com/Pittsburgh-Automo ... B005T4JMYM

Thank you very much for information. (i think my friend mechanic mus have that in his toolset)

my oil use is 1 liter for about 10 000 km wich is on the edge of "normal" oil use from the service manual.

even if not catastrophic, it is way up from almost zero oil used before the camshaft/prings & retainers surgery.

will post plugs photo and leakdown results.

Here is a new shot of the spark plugs in the right order
plugs are new + 1000 km.

please write if the folowing is ok :

1 - ok = 0
2 - ok = 0
3 - a little lean = +5 % ?
4 - rich = -10 % ?

do you think i can go for those values in fuel cylinder trim ?

Judging mixture from spark plugs is not a precise science now that lambda meters are common.

Did you do a leak down? Have you had the injectors flow tested?

sadly no, i have neither flow tested injector nor done leakdown. (will try and do that when i can)

would be great to have one lambda per cylinder...

the only thing i can say is that the car emit absolutely no smoke nor smell.

ans it runs fine both pull and sound.