The T-Spark flatspot: fuel-related?
What's the current fix (or fixes...) for the cold-running, sub-3000rpm flatspot that a number of T-Sparks seem to suffer? I've not been on here much and as a result I'm a bit rusty.
I only ask because like many, my car has this low temp/rpm rough-running (<3000rpm, upon after which it clears its throat and runs fine), but not all of the time. I've only noticed it when back home in (south) Essex. Here, in west Wales, it's fine, only happening when I've got remnants of fuel from back home. Which got me thinking: could this flatspot be related to the quality of fuel used, or to be more precise, when the fuel is produced? Back home, the fuel from all of the stations comes from either the Coryton (BP) or Purfleet (Esso IIRC) refineries, regardless of where I actually buy it from. Yet, here in Wales, I'm guessing the fuel comes from Milford Haven (Texaco I think). Back home, there's the flatspot, yet here, nothing; as smooth as.
Any ideas? I know fuel can vary depending upon where it's produced, but would the T-Spark be that sensitive?