Denso Iridium IXUH 22 Spark Plug for Peugeot 308 THP 140

The plugs arrived today ... in an very conventional box ... nothing fancy except probably the coating on the spark tip.. got it regap at 0.7mm before delivery and reconfirmed again myself.

I have bought some tools just to remove the oem plug and also fit in the new one. OEM requires the bi-hex 14mm tool, whereas Denso uses the 16mm hex.

Also propped myself with a gap gauge ...for future gapping purpose ...

First thing to do is remove the old plug (remember to do this when your car is cold else you risk damaging the thread - I have to wait till early in the morning), there are some residues on the tip ... but it is not hard residue apparently it drop off after some movement. Brownish means normal. No melt or excessive carbon, combustion is healthy - measured the gap as well, apparently around .75mm exactly like Peugeot recommended.

Initial run ... it certainly does add a bit of oomph ... very subtle but it is there .some inherent smoothness as well. Definitely recommended for those looking for something extra. But i guess if you add normal plugs after 10k also you will feel some difference but anyhow i feel that it is more obvious than when i change the plugs at 40k. Anyhow since this is only a tad more than OEMs .. im gonna stick to this in the future.