poor acceleration PEUGEOT 207 Hatchback (02.2006 - 12.2015)

Hello

My car has poor acceleration when first started, then it improves and drives well, has been like this for years. So far its been a mistery to all who have tried to diagnose the issue.

About the car:

– Appart from that it drives perfectly, up mountains, long drives, idles perfectly.

– Temperature solid, no fluctuations even up mount troodos in Cyprus.

– When running accelerates well, no driving issues, light and straight stearing. MOT all good.

– Fuel consumption very good 13km /lt

– No noice no engine issues, oil good no burn, water good.

– The car was my mothers, she was old so only got driven when I vissited, so for the last 10 years it “sat around” alot of the time and the temperature in Cyprus gets very hot.

– its had this issue for at least the last 8-10 years but no other adverse affects to its driving.

– To date120,000km

– I drive it everywhare

What have I done (mechanics) to solve the issue.

– Serviced

– Diagnostics x2 show no issues, all working perfectly, no electronic issues, fan sensor changed, all good.

– New battery

– New plugs

– New fuel pump.

– Changed timing belt at 100,000km

– Mechanic said he reset the computer.

My only guess now (am not mechanicaly skilled), given I was assured the issue was not electrical, is the clutch. After many years of sitting and not driven can a sticky clutch (if there is such a thing) be tha cause. The lack of acceleration seems to be much more evident during the first start of the day; then not so obvious.

Why its important to me, is that it can be dangerous during the first minute or two if the accelarion fails at a junction or roundabout.

Your input would be appreciated.

Thanks

Nick