225 Hesitation in revs and lumpy under load. TDC?

2007 Megane 225 full fat.

Got a problem where the car starts ok but get a lumpy feeling at idle.

If I "blip" the accelerator I get a hesitation and then the revs pick up.

Once the revs have picked up they remain constant and I don't notice any hesitation or lumpiness. Certainly can't hear anything like a misfire.

However, the moment I put the car under any load (in gear and start to drive, either forward or reverse) I get a lumpiness that is constant in rhythm - like a misfire. If I disengage any load then idle feels ok again but if I blip the accelerator I still get the hesitation before revs pick up.

Changed all 4 plugs.
Had non-CLIP diagnostics - healthy

Have read that TDC could be culprit?

I'm not sure coils or injectors because idle "seems" ok, and so too does when I press the accelerator after any immediate "hesitation". I.e. it'll seemingly hold at, say, 3000rpm without feeling any lumpiness.

On the 225 where is the TDC sensor located? I get "Top Dead Centre", but I can't find in the downloaded workshop manual where there location and steps are.

Also, if I replace the sensor does any reprogramming or other procedure need to be done? I've found "something" in the manual that relates to TDC in the ignition section that covers diesel and petrol but it talks about some reprogramming and such steps as driving the car up to a certain number of revs and then taking feet off pedals to let the car stop and allow idle torque to take the load? Is it as complicated as this or have I misread/misunderstood?

 

Plugs changed. Coils not yet.

The diagnostics just had done (not CLIP) didn't suggest a faulty coil (no engine codes at all), but would they not throw up an error code?

Also, wouldn't a coil have the symptom constantly?

Cheers

 

P.s. idle is within normal. Certainly not higher than I've ever experienced.

 

Thanks for all the suggestions... Turned out to be a coil pack.

Phew.