Warm starting Issue

[richardw]

So my 2012 260S Trend Euro 5 is causing some grief when warm starting

Cold doesn't miss a beat , started on first turn of the key no hunting or other irratic behaviour

Warm / Hot I need to hold the key on crank for a few more seconds and eventually will start and tickover as normal but during those few brief seconds sounds like a bag of bolts

I've changed the injector leak off seals and cleaned the cam sensor so far - no joy

I'm fairly sure this started after clutch and DMF install , but it had a new crank sensor at the same time

I'm getting RPM and Sync on cranking ( see attached ) and fuel pressure seems ok - so now lost - anything else I can try on ForScan ?

Any other ideas ? - could the crank sensor be too close to the flywheel ?

[TheCake]

might be worth checking dpf/egr

[richardw]

Its a thought - although I'd of expected codes in forscan - and I don't have any

[richardw]

Well swapped out the crank sensor this AM for genuine ford , alas no progress

Great cold starter , tricky when warm

So that leaves me -

Air getting in to the fuel system , somewhere ?

Injector issues ? - Although why just an issue when warm

I note I get no glowplug light at all when the engine is warm , even momentarily - is this normal ?

[Col 52]

I had this on my 2008 350 rwd. I thought scv or prv. But turn out the starter motor pinion cog teeth were wearing making it difficult to start when warm. But started fine when cold. Might be worth undoing the two 13 mm bolts etc to have a look at the starter motor pinion?

[richardw]

Now there’s a thought - starter motor , especially as had new flywheel

[richardw]

It was the starter motor , swapped out and its resolved - I still can't get my head around why as its not cranking any faster

Thanks all for replies

[Altransit]

I still can't get my head around why as its not cranking any faster

It's because the old starter was probably needing more effort to turn the engine over, which "robs" critical volts from the system during starting. If the PCM doesn't see enough voltage during cranking, it won't allow the injectors to fire.
I've recently had a similar issue with my Mk7, and a new starter sorted it straight away