Starts First Time But 'Rumbles' For First Couple Of Seconds?

[EViS]

A handful of times over the past couple of months, my 2005 mk2 Ranger starts first time after the glow plugs have heated up however it doesn't start 'smooth'. The engine seems to 'rumble' in a jaggedly manner for a couple of seconds and a light 'rattling' sound can be heard from within the engine bay. This only happens every now and again in the morning from a cold start and the truck drives fine there-on-after.

I probably haven't explained that too well (?), however if anyone does understand what I mean, do you have any idea what may be causing this?

Edited by EViS on Thursday 15th November 10:57

[one eyed mick]

What mileage ? if its starship ,injectors ,valve probs ,hydraulic cam follower , change and flushe with Forte or sim and treat fuel system to flush also my routes before spending lotsa £'s

[EViS]

Mileage is 75,000 miles.

[MGJohn]

Had your engine been a petrol my first thought would have been worn main and/or big end bearings. Many moons ago had a petrol engine do as you describe on cold start up and it had an accurate Oil Pressure Gauge. It would sometimes be four or five seconds before the gauge would register any pressure and a few seconds later, pressure would be up to near normal for a cold start. I suspected than with worn bearings the oil took its time to fill the gaps. The engine flew once warmed up though but, sounded like a high mileage diesel on cold start up.