Technical 500 Twinair late 2011 feels like it's in Eco mode all the time

[johnsimister]

Hi, I haven't been on here for a while thanks to my Twinair's good behaviour, but recently the performance has dropped right off. The symptom is that it feels exactly the same in terms of turbo response and hillclimbing ability in normal mode as it does in Eco, which means quite lethargic, as if it has defaulted to the Eco map.

Is that possible? A couple of years ago it had a new turbocharger owing to wear in the wastegate shaft and actuating rod, following a period of slightly gutless and hesitant acceleration, after which it felt fine if never quite as punchy as it did when I bought it at just under 8000 miles. (It's now coming up to 50,000.) The performance then started dropping off again, and it suddenly got worse when cruising on the M1 a couple of weeks ago upon which the engine managment light came on.

My local garage took out and checked the filter in the Twinair unit, which was perfectly clean. They also ran a diagnostics check, which revealed fault code 'P0244: overboost solenoid valve intermittent 1'. They cleared the fault and performance was back to its previous slightly less weak state.

I have now replaced the solenoid valve (part 55203202), in the hope that a fault in the old one was preventing boost from building up as much as it should. I was hoping this would be the final cure, but no. The car does go a bit better, doing that good impression of being permanently in Eco, but there's obviously still something wrong.

All ideas gratefully received.

Thanks, John

 

[jrkitching]

it suddenly got worse when cruising on the M1 a couple of weeks ago

E10 fuel?

 

[johnsimister]

Good thought but I doubt it. The performance was poor before E10 arrived, and why would E10 trigger that fault code?