Lightmania

Hello,

I have Lexus ct200h 2011 3 months ago i changed my spark plugs from the main factory since then my fuel consumption is crazy before changing the plugs my average was 6.0L/100km now it is on 7.5L/100km so i went on checking everything but nothing is wrong...so i remembered i have my old plugs did not trash them so i want to compare between the new ones and old ones. So i found out that the new plugs are SC16HR11 my original ones SC20HR11 that must be the reason

i want to know what are your thought guys? what would you do in my place? any tips would be great

thank you all

KKM

Did you gap the spark plugs properly? That could make a difference.

qwerty66

iTrader: (1)

I believe your new plugs are a couple of step colder than oem
I recommend getting the correct ones

roadfrog

Did you use Denso plugs? If not, I would question the brand you bought. On the LS forums, many member had issues with anything other than OEM (Denso). In one case, the issue was severe (though I can't remember exactly what, other than rough idle, hesitation and the like).

Lightmania

Yes Denso plugs

so this time i decided to change the style of driving to check what is the problem.

so now kept the average screen on tried to go slow as i can and not push a lot of gas which now its forever to reach 40 or 60 km/h but i controlled the average to 5.5

but the things i noticed on highroads my fuel consumption is very low but while driving in the city is where the fuel consumption high

so now i controlled the average but i dont know how can i hold up this because it really takes forever to accelerate

do you guys recommend to change the plugs or no?

any tips?

roadfrog

Well, as QWERTY stated, it ounds like your plugs are too cold. Did you check on that?

Lightmania

how can i check it?

roadfrog

Ask your dealer what they recommend. I'd be inclined to go back to the hotter plug.

qwerty66

iTrader: (1)

The part number tells me that your new plugs are too cold (16 vs 20)
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Go to the dealer and get the correct plugs and your issue will be fixed

qwerty66

iTrader: (1)

I looked into the issue a bit more
The 16 is the recommended replacement for the CT as it's actually a hotter plug compared to the 20. The hotter plugs will keep deposits from forming on the electrodes and ground straps as the engines doesn't stay on all the time, therefore can't build up consistent heat to burn those deposits off.

So your issue could be the switch over of winter blend gas?