From the description of the spark plugs. Over-fueling. Sticky valve problems? Screwed injectors?
Not sure really, but over-fueling bit sounds right.
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<font color="maroon">'98 Fiat Marea Weekend ELX (1.8 16v).</font id="maroon">
- Kenwood MP3 head unit
- De-Restricted standard air box
- NGK VX Platinum plugs (BKR7EVX)
- Toyo Proxes T1-S (205/45) tyres on Stilo 7-twin-spoke 16" alloys
- Quad LED blue sidelights
- Gaiters in a sorta silver/grey colour
- Richbrook Aluminium Red Uni-Hex gear knob with FIAT logo</font id="Verdana">