white spark plugs?

[NeX]

hi all,

what does it mean if the ends of your spark plugs are white?

i used to know but now i can't remember lol,

just changed my plugs and the old ones were bleach white... i think that means it's lean doesn't it.

thanks ppl

(BTW i thought this would be best in general chat rather than k11 tech cos it includes any car )

 

[Arnold]

Check the back of the haynes if you have one mate. I dont have one to hand, but there's a picture of different types of plugs and will tell you what it means

Mine were slightly white recently and i think it was a sign of a weak mix, but not bleach like yours

 

[sonic]

its a sign of the plugs being overheated, often associated with a weak mixture.

 

[NeX]

thanks ppl,

surely ECU engines should adjust so the mixture is always level?

 

[sonic]

it should do, have you got the right grade of plug in ?

 

[NeX]

ooh grade, now you're getting complicated lol,

they are them four point ones... now upgraded to these irridium ones? i think thats right...

 

[bobsp16]

White plugs mean that the engine is running lean,have you fitted an induction kit this will make it run leaner or is it could be because your lamda senser is play up,
I no somebody that fitted an induction kit and it also run lean so he fitted some bigger injecters out an 1.6 along with his induction kit and it made a big differents and the plugs were the right browny colour.

just an idea.

 

[Ian]

that wouldnt work with a k11 bob. it would just overfuel the car.

 

[lewic]

some pics here! http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

 

[Fordy]

if someone wants to try it ive got some fully working 1.6 injectors with the fuel rail for sale

 

[bobsp16]

that wouldnt work with a k11 bob. it would just overfuel the car.

why mate it work with vauxhalls

 

[Ian]

because its opening the larger injector for the same amount of time as the standard one which overfuels the car, i know from first hand experience.

also, a k11 with an induction kit won't exceede the maximum flow rate of a standard injector. I'm not fully sure on how the CG ECU works, but i would have thought with a higher flow of air, the ECU would up the fueling. But im sure ed/pete/micra charge could asnwer that question.

 

[micracharge]

You are quite right Ian, larger injectors on the stock ECU will simply open for the same duration as the stock ones, and thus depending how much bigger they are than the stock injector - could overfuel like a good'un. A great misconception here is that the lambda sensor is the all-seeing eye that fixes fuelling, that sadly isnt the case. Lambda control is only active at cruise and light load and does not govern the mixture on full load, this is the time when the plugs will start to tell the tales of how the engine is running, mixture wise. The stock sensor is narrowband and can only accurately meter a range from about 14.5 - 15.5 AFR (basically a little either side of the stoichiometric point of 14.7 for Gasoline fuels), this is nothing like rich enough for full load so the lambda control is turned off and the car reverts to its mapped data only, which it cross references in a table of Airflow vs. RPM.

What I have noticed since I have been on this forum is that with the Micra being such a cheap car, very few people put money into tuning them properly (understandably too, for financial reasons, and often just commonsense) so the standard of tuning in the Micra scene is actually quite low. Fit the bigger injectors by all means if you have sufficient mods to utilize them, but get something to control them properly. Hopefully soon my Megasquirt project will prove that you dont need to spend Skyline-style budgets to have a well sorted properly controlled standalone management system on your Micra

As for your plugs, if they are white ONLY on the tips and black at the base, dont worry too much, if they are white all over. Worry.

 

[59 bhp is more than enough]

ah now i see how the ecu is open and closed loop. when you done with the mega squirt post up a review if you have time.

 

[NeX]

some pics here! http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

that is a top site

mine look like number 20 so thats ok, just me being paranoid lol

 

[Yom]

The other problem I have identified in your post is you appear to be using Bosch spark plugs.

 

[NeX]

The other problem I have identified in your post is you appear to be using Bosch spark plugs.

LMAO yea well i do shop at hellfrauds lol,

BTW what would you recommend? i know nout about good makes of spark plugs

and HT Leads, i have some VERY budget ones :down:

 

[Ian]

get some regular NGK's they are like £1.80 per plug or something.

 

[NeX]

cool thanks

 

[Ed]

What I have noticed since I have been on this forum is that with the Micra being such a cheap car, very few people put money into tuning them properly (understandably too, for financial reasons, and often just commonsense) so the standard of tuning in the Micra scene is actually quite low.

So true,
Its understandable for people with bolt on stuff, but it fustrates me to see this with turbo conversions etc, almost always resulting in a meltdown.

Ed