For the last week I've been having an issue with my RPM boosting highly for no reason.
I drive a Peugeot 307 1.6 HDI S 90BHP.
Whenever I shift from 2nd to 3rd and start gassing it up a bit moving up to 1800 RPM the RPM will suddenly boost highly to 2200 for a few seconds and then drop down to normal RPM climb as you would expect. Now I'm not pressing the gas pedal any harder during those times, just keeping it as is as. This will also happen in 4th gear but not as much as 3rd. I've noticed this problem a month back but it happened like once a week however now it happens almost every time.
The car is not modified in any kind of way. Had its engine oil changed about 2 months back. I don't know if its the gears slipping or maybe air in the engine and whenever it circulates and pushed it through it skips ?
Is this normal behavior or am I missing something ?