Some of these experienced timing chain problems which stretched ( Renault)
You have to remove sump on these which is a pain because gear box stops it removing !!
Therefore need to move lossen gearbox to improve access.
Hi have done several of these two of my families and my own a few years back
Allow a day agree with Tony can be hard to get back on but if 2 pairs of hands just for putting gearbox on (did it on own after first time Replace release bearing why gearbox is off) it’s basically in Haynes manual but...
Before you remove speed sensor check battery isn’t on way out can cause fluctuations
If ok remove sensor held by 10mm screw/bolt You may need to slightly twist sensor to remove it
Disconnect plug now Check speedo by using a multimeter set at ac across two terminals in Block if you turn speedo...