So how are the MTLs holding up these days, Dan?
All I can report is that the Beru's I put in easily more than a year ago now (replacing ruined OEMs which had gone in just before I bought the car) and have had lots of abuse are still A-OK. Not bothered at 30ish quid a pair.
What's this about needing official Renault plugs though? I wasn't aware they made their own
... just got whatever it is that GSF supply (NGKs? Champion? Beru again? erm...) and having no worries.
In fact now the alternator's been replaced I'm getting impressive economy for a 1.6 petrol (never mind an 11 year old one) and sustained good performance. The worst engine troubles I see are dodgy idling (the control servo's been knackered from day one) and occasional flat-spotting in the first few minutes of running in the cold and damp... again, the car's always had that and it clears up within a half mile.
IMVHO trying to play spot-the-difference in performance without using numerical instruments is a nonsense, particularly if you're trying to tell between two periods of good running with a bad patch in between as that distorts your perception. The "butt dyno" lies more often than not. Unless of course it's quite a gross change... e.g. when the first pair of
went, the car would barely move at low rpm / wide throttle and shuddered regardless below about 3500rpm. When the second set started to fail, it was a lot more subtle and I had to do a 2-way stopwatch measured 0-60 run to be sure I wasn't just imagining it... power was down enough that it was taking 14 seconds instead of 10! Unless you were suffering from gradual degradation/actually generally-crap
(to the point that the spark was only just strong enough to ignite just-enough of the metered fuel for smooth running) instead of a sudden failure, or are exceptionally sensitive, it seems unlikely that you could tell a difference in everyday use...