• Registered users are encouraged to enable MFA/2FA to add an aditional layer of security to their account. More information can be found here: https://www.ncsc.gov.uk/collection/top-tips-for-staying-secure-online/activate-2-step-verification-on-your-email

EP3 spark plugs a little too white?

Messages
2,229
Trying to locate the reason for my car being about 10% down on power so I took the plugs out. They are fairly white which indicates the engine running too hot or too lean. Is it worth me changing to a different heat range?
Anything else I could investigate if it's running too hot?
 

Attachments

  • 20190527_120349-1209x1612.jpg
    20190527_120349-1209x1612.jpg
    368.4 KB · Views: 22
Do you have a decent OBD II reader and the torque app (assuming android phone)? If so you should be able to test the lean hypothesis.

You're already running iridiums, if it is running lean then I'd be more concerned about getting it to the right stoichiometric ratio rather than about the heat as the first issue.
 
I do have the torque app and obd2, but I'm a bit useless with it. Can you tell me how I do what you suggest? Thanks Mike!
 
https://acurazine.com/forums/4g-tl-...-fuel-trim-affects-engine-performance-963982/ has some really good instructions.

In short, look at the STFT and LTFT readings once the engine is warmed up (take it for a 10 or so mile drive). Park it somewhere and leave it running and look at the STFT (short term fuel trim). If it's heavily positive (more than 10% like the posting says) then it's running more lean than it should be. The long-term trim might be worth checking to see if this is a longer-term trend too (your plugs might indicate it is, but it's worth checking either way) and whether it's getting worse.

Having someone in the car with you as you drive (or using a laptop with decent logging, or getting Torque to do the logging for you) might be worthwhile too, as being parked only shows you idle readings.
 
Back
Top