ES9J4S Spark Plugs Replacement: Awesome effect on the Engine!

0.55mm +/- 0.2mm for the XFU and XFW, is what I have found.

I think you would struggle to get 0.1mm...
Thank you SLC206 but that figure is different to anything I can find. Sorry I wrongly quoted .1mm - in fact the recommended gap I found for the S engine is 1.1mm
 
Well you haven't said what engine code you have. What's the three letter code in your VIN?

I found another reference to an XFZ:
xfzplugs.jpg


xfwplugs.jpg
 
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From the French version of the same doc I posted for timing--
There's a Bosch number. You can look up equivalents. The gap is 1 mm.
bougies.png
 
Do you have an owner's handbook?

Go to the address below; change the language to English Australian in the bottom right corner; Select Handbook Pack; then Peugeot; then 406. The different models are shaded in the 406 image.

 
Do you have an owner's handbook?

Go to the address below; change the language to English in the bottom right corner; Select Handbook Pack; then Peugeot; then 406. The different models are shaded in the 406 image.

Thank you yes I have the original owner's handbook but can find nothing in it about plug gap. Mind you its indexing system is little short of chaotic.
 
One of our members from Nigeria writes about this ES9J4S engine. His blog is at
 
Thanks COL. On recommendation I have NGK plugs for my engine, but remain unsure about correct gap, which on-line sources quote variously as .8, .9 and 1.1mm. Grateful for any clarification.
Nothing wrong with NGK plugs. My manual for the Laguna V6 says 1mm gap.

Spark plugs come pretty much correctly gapped nowadays, I do check the gaps but rarely need to adjust them.
 
Further thanks Simon. The engine in my car is XFXPSA0132112. I am using NGK

PLFR5A-11 plugs as recommended by French car specialist here.​

I have ES9J4S / XFX and also use NGK PLFR5A-11, 1.0 mm gap. When measured new, they were all easily within tolerance (+/- 0.05 mm) i.e. 0.95-1.05 mm.
Being an OCD engineer, I try to make them all 0.99-1.01 mm o_O
 
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I have ES9J4S / XFX and also use NGK PLFR5A-11, 1.0 mm gap. When measured new, they were all easily within tolerance (+/- 0.05 mm) i.e. 0.95-1.05 mm.
Being an OCD engineer, I try to make them all 0.99-1.01 mm o_O
Sincere thanks. That is the margin I have adopted. Very grateful. Regards, Bruce.
 
Replaced the NGK iridium plugs in our 2002 ES9J4S recently for the Bosch 5960GO plugs. A noticeable improvement - super smooth.
 
As per the original text in this thread over 10 years ago by Ikenna351. 5960GO is the Peugeot OEM number or better known as Bosch FR8 SPP332. I managed to get 6 of them posted online from Automotive Superstore for around $100 delivered. Shop around as you can pay twice that. https://automotivesuperstore.com.au/bosch-fr8spp332?filterVid=18147
Apparently they have a double platinum electrode at both centre and ground. Gap is listed as 1.05mm
 
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