300tdi sluggish in mornings

hi chaos,
my 1996 300tdi defender runs very sweet.
no smoke at all on start or running-no leaks, serviced every 6000miles, new filters and battery etc and I've also flushed out intercooler and fitted silicon hoses. my boost gauge is showing good turbo pressure...

so....why in the mornings does it drive like I'm towing the titanic for the first 5mins until it's warmed up a little-seems like no turbo even though boost gauge reads good! is this normal or shall I check turbo oil lines for blockages?

I have no egr on this model

thanks all

perfectly normal. everything is stone cold so the oil is thick and can't move around so well. Just think of it as like when you wake up, you don't spring out of bed and go straight out to work as soon as your eyes open, you need a little time to wake up too

Yeah, mine does to and I'd say its normal. In fact every car I'd ever had is the same.

Engines are designed to work at an optimum temperature. As Jase750 says, the oil will be cold and viscous and will take a while to get pumped up from the sump to around the engine. But not only that, all the engine components need to get up to temperature also.

For example, pistons are not perfectly round when cold. They are microscopically oval and irregular, designed such that when they are up to temperature, they've expanded to become round. Also when fitting piston rings you have to leave a tiny (manufacturer specified) gap to allow for expansion when hot. They basically close the gap when up to temperature.

All other internal engine components are designed with the same principles in mind. So until they get up to temp, all engines will run a bit rough.

Try changing the Cat for a De Cat pipe. For a 1996 Disco there is a possibility that the cat may have collapsed and causing back pressure.
But that can be very noticable with a very hot smell when hot and no power pretty much consistant

Ive changed the injectors at 130-150k on my last two Disco's that seemed to cure sluggishness at all times...
Both 6k serviced & manifold/intercooler degreased.
Both without cat & EGR.

Either the cold start mechanism isn't working or it needs the fuel turning up a sniff.

It's purely down to engine temperature, you need heat in the engine for good combustion - hence the need for glow plugs on a cold morning. I've driven new L200s that are exactly the same!!

I always try to start my truck up 5-10 minutes prior to going anywhere that way by the time I've trundles 1/2 mile up the drive the needles in the right place (the only sluggishness on mine is the tuning lol )

On all the diesels that I have worked on the glow plugs only work pre cranking the engine, at all other times they are dormant so once the engine has fired the glow plugs wont affect the running.

I agree you need heat but you also need fuel

cheers for your input guys

landowner said:

On all the diesels that I have worked on the glow plugs only work pre cranking the engine, at all other times they are dormant so once the engine has fired the glow plugs wont affect the running.

I agree you need heat but you also need fuel

Click to expand...

Also most diesels will not start without preheat of somekind as the cranking power provided is not great enough, it's not until you get on tractors n the like the crank power and battery ah are great enough


Try changing filter ( unless you have) this cold weather and the new 3% diesel available at petrol stations gums up the filter

landowner said:

On all the diesels that I have worked on the glow plugs only work pre cranking the engine, at all other times they are dormant so once the engine has fired the glow plugs wont affect the running.

I agree you need heat but you also need fuel

Click to expand...

Glow plugs are needed pre-cranking because everything is stone cold, and the diesel is pretty thick. The Glow plugs heat the jet of diesel, allowing it to burn more easily. Yes the engine will start without a pre-heating system when cold, but when temperatures drop to -10, you'll be cranking that engine for a little while, thereby introducing heat into the engine, until it finally starts. As the engine warms up, so you get better combustion and better performance. If it was a fuelling issue, the gentleman would have continued problems regardless of how far he'd driven.

Obviously it depends how bad this sluggish problem is. If it's as severe as you not being able to pull off from a junction safely, then there's probably another problem; lift pump, turbo, timing out, any number of things.

Just to say mine is the same (1998 300tdi with Twisted intercooler and silicon pipes) - and also the sluggishness extends to the gearbox.

I have always put it down to being cold / a slow starter, as it picks up once you get going.

Cheers,

Caddy.