Mk1 Ka Failing To Start

[Alexsimpsn]

Hi all, new on here but I've been on as a guest quite often looking for advice :)

my problem is this, The engine will turn over, fail to fire and cut out. also whilst cranking it if you even so much as touch the throttle it'll make this god awful sort of grinding noise and immediately die. any clues?

recently had to change the thermostat housing as the old one ruptured and leaked coolant everywhere (this of course caused it to overheat and cut out at the roadside).

also recently replaced the plugs and HT leads as the old ones had corroded causing misfiring, but this was at least a month prior to the coolant issue.

oh and it's the Duratec engine.

hope at least someone will have a clue as I'm stumped frankly.

Many thanks :)

[Alexsimpsn]

quick update, seeing as there's still no response lol :)

checked all the fuses, no faults there. gonna check the plugs when the weather allows as I don't have a garage and don't feel like standing in the !Removed! rain messing with electricity, but as I said they're new plugs so I doubt that they're at fault. You never know though!

also dashboard diagnostics is showing a Dt 412 code, which I'm led to believe relates to the air intake/ air-fuel mix? if so could that be the cause of my problems and if it is how would I go about fixing it? note that in order to replace the thermostat housing I had to take the air filter off, but it all went back in place and connected nicely so I'm unsure.

any help would be REALLY appreciated as I don't want to resort to forking out for a garage lol :)