My (more than usual) sluggish 300tdi

Just read this thread and you have nothing to worry about the smoke at start up, all 300tdi's do this as they start up rich to aid starting and mine also has visible smoke at idle, faint but visible. Mine used to run hot which also made the auto run hot because of a partially blocked radiator, I got it rodded out and that fixed the problem.
I was wondering if the pin that runs on the tapered shaft below the boost compensator diaphragm could be stuck or seized which would make it feel sluggish but I'm not sure if that would allow your egt's.
Re torqueing your head bolts, I'm not sure if you need to or should do that with the composite head gaskets, as the head bolts are torqued to spec and then turned a specified angle (60 deg?) but someone else may know the answer to whether you should or not.
14 psi is close to original spec, mine ran 13.5 standard, until I upped it to 18psi.
Have your valve clearances been checked lately?
Are there any restrictions on the air inlet side?
Injectors, well they could need a clean, they may not be atomising the fuel properly allowing a good burn of the fuel, they could be dribbling, or releasing fuel at too low a pressure. Does it smoke badly under load?

Thanks for the reply Pawl,
Re the pump, I'm getting hot egts so I assume that it's getting fuel ok... But I'm sure there's more to it haha.
Have checked valve clearance in a long time so I'll do that. While the rocker cover is off I may as well check the torque on all the head bolts.
I'll clean the inter cooler, replace the the pipes, new exhaust... Then I'm pretty well out of ideas - and cash!

I'm with pawl on the head bolts. Don't touch them. The symptoms you're describing aren't a typical head gasket issue, so I would be hesitate to start playing with such things. If it ain't broken, don't fix it. You dont want to add to the list of problems. Part of the difficultly here might be that you have more than 1 problem... Adding more will make it a nightmare to diagnose.

Valve clearances are a good one.

Have you taken all the intake and turbo hoses off and looked inside them? I still say that's a easy and $free check before anything more serious. Blocked intake or blocked exhaust sound plausible, but I have no idea how an exhaust gets blocked. Intake hoses can come apart inside though.

Yeah I took them off, cleaned them out. They seemed in tact, but I don't have a whole lot to compare them to. They did however feel "warn" or brittle. I'll be replacing them anyway. The main intake hose from the air filter to turbo looks like its being sucked in, as in, the walls of the hose are coming together. If that is a result of it being weak and not coping with the sucking force from the turbo, my guess is that will drastically reduce intake capability. Sound legit?

Need more time at home to actually get my hands dirty!!

Edit: re exhaust, I think the cat converter honeycomb can break down, but the aus diesels don't have one! (Afaik)

Quote:

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Originally Posted by Flexual

Yeah I took them off, cleaned them out. They seemed in tact, but I don't have a whole lot to compare them to. They did however feel "warn" or brittle. I'll be replacing them anyway. The main intake hose from the air filter to turbo looks like its being sucked in, as in, the walls of the hose are coming together. If that is a result of it being weak and not coping with the sucking force from the turbo, my guess is that will drastically reduce intake capability. Sound legit?

Need more time at home to actually get my hands dirty!!

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Mate, what you have there is a delaminated hose! This is quite likely a large portion of your issue. I was having high EGT's and seriously :censored: performance when I had intercooler\turbo hose issues (one of mine was starting to delaminate, the other had a hole). Swap them out with a decent set of silicone ones and you may find most, maybe even (hopefully) all of your issues gone!

The silicone hoses will stand up to a pretty damn good workout, plus, they are pretty to! I got mine from British 4WD in Tasmania via their Ebay store. They are reasonably priced and the shipping was quick. Three choices of colour as well from memory.

I cleaned my intercooler out with some carby cleaner at the same time as I did the hoses, wasn't heaps dirty, but the carby cleaner in the bucket at the end was still pretty dark.

Good luck,

Chris

Thanks Chris I hope you're right!
I'll report back:)

^ x2!!!!

That hose is almost certainly the problem, quite possibly the entire problem.

Also, I will refer you to post #2 in this thread. :p

Haha yeah yeah:p I did go through and inspect them at that point, but not really being aware of what to look for I guess I looked passed it. I didn't see any delamination, but without having seen it before, I wasn't what I did or didn't see.
The hose sucking in was only noticed this morning!

Yeah fair enough, I've never actually seen one either, just going on theory. Not long after I purchased my Disco I purchased a set of silicone hoses and haven't touched them since. They're not that much more expensive if you buy online, so I would definitely recommend them.

Bought some silicone intercooler pipes, a new air box - turbo hose and getting a friend to give me a hand with the valve clearances and were going to put in a timing belt kit with all the peripherals.
Fingers crossed:)

Thanks for all of your help with this issue guys. It's great that you've all so willingly passed on your knowledge to such a green Disco owner!