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Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22899
Experience:  BEng hons Mech engineering, in auto industry 22 years
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Hello. I have a 2010 Caterham Roadsport 175 SV which has been

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Hello. I have a 2010 Caterham Roadsport 175 SV which has been factory upgraded to 220 bhp. The car/engine has done 6000 miles from new. It has had Caterham factory services at specified milage.
Most of the time the engine is great and responsive but occasionally, on some journeys at speed it hesitates/falters/seems to loose power in 6th gear, responding to increased acceleration although sounding a bit rough. Dropping down to 3rd gear and accelerating give more reliably better acceleration and after doing this up and down shifting a few times seems to clear the problem. Recent blats of 200 miles or so have shown no problem but a more recent 200 mile blat showed the above symptoms after about sixty miles, verified by my passenger.
About a year ago, Caterham factory collected my car on a low-loader due to this, but on test driving it for a few miles, servicing it at the factory,and then test driving it again for a few miles could find nothing wrong. Any ideas would be greatly sppreciated. Harry Davies
Hello Harry

I'd 1st suspect that there's an issue with the fuel pickup inside the tank

if the issue goes away with a full tank then this woudl bear this out

and if that’s OK then get the fuel pressure checked at the injector rail with the engine running. This will show if the electric fuel pump and regulator are in good condition.
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