Problem turning off

Have noticed over the weekend that whenever I stopped and turned off ignition it was like the engine wanted to restart, it wouldn't go the whole way to re starting by itself but engine made a couple of jumps before it finally cut out.... Any ideas? Seems to be after long runs. It's a series 3 petrol

Pre ignition. Glowing parts igniting residual fuel.

Jasper.....see thread on petrol additives....posts by myself and Kommer.....Chris

chris7 said:

Jasper.....see thread on petrol additives....posts by myself and Kommer.....Chris

Click to expand...

Cheers Chris I have been following those actually, as it happens I put the additive in on Saturday as a tester can't say I noticed that much change but I also adjusted the idle as it was a bit spluttery for want of a better word.... This was all done after the starting stopping started! Bit of a novice so any basic things I should look at?

Mines a rebuilt Engine..and set up correctly yet I experience run on after a long journey .....I find stopping and letting it idle for a couple of minutes cures the run on problem....but you can buy and fit an anti run on fuel cut off solenoid...the lead substitution additive wont have any effect at curing run on.....you might just need a head decoke...head off valve clean and regrind etc

X1 on the run on. I get it too after longer runs not all the time, unrelated to the unleaded/ leaded issue. For me its a non issue.

Thanks for all the advice, brought it to a local landy mechanic who cleaned all valves. If it's a non issue then I'll just try letting it idle before o turn off and see how it goes.