Quick remap cures 2.0 HDi 160 flat spot.

[Dublin Tony]

Dropped my C5 in to my friend Mr. Woods for a service. He offered to put it on his rolling road to check the output and seeing as this was the car's first service since I acquired her last year, I thought why not?
The good news is that even after 200,000 kilometres the engine was putting out 161 bhp and about 245 FtLb of torque. The bad news was the big flat spot. Max torque was available at 3000 rpm (way to high). I had noticed a reluctance and poor throttle response from the car, but thought that was just the way she was made - it is a heavy car after all. Woodsie sent me a photo of the dyno screen and you can clearly see the flat spot and late torque curve. I thought I'd be looking for a new MAF sensor or some such, but my pal came up trumps - a remap sorted out the power and torque curves and found an extra 28 bhp and an extra 60 FtLb of torque! That's about 190 bhp and a whopping 300 FtLb of lovely torque.
The throttle response is much improved and the car pulls like a train from just over 1000 rpm like it should, with a nice even power band. All in all, I'm a happy bunny .

http://postimg.org/image/xwsslzut5/5311ec46/
http://postimg.org/image/gl35d8m3f/207add7c/

[Lighty]

That's a decent result, but you shouldn't remap a car to cure a fault ??

[Dublin Tony]

Fuel economy has improved too. The trip computer was giving me a respectable 5.8 l/100 km (48.7 mpg). Post remap, it's reading 5.2 l/100 km (54.32).
I know that the trip computer is not that accurate, but it does give a reasonable idea of my fuel economy.
A few days on and the car is just so much more driveable. I don't have to down-shift to overtake and all in all it's a nicer drive. Let's hope the clutch agrees!