sluggish 300tdi

Google back, not too far, as this has been done a few times recently.

Yours sounds like a hose internals collapsing ...

Yeah found some messages thks, sounds like turbo hoses is a good place to start looking.....

cruise control not working either, possible related? Is the cruise control vacuum system connected somehow to that of the turbo?

Mine's not quick, the 200 was faster.... TonyB

Yes, a 300 Tdi auto is pretty slow even when A1.

I had a similar problem with my manual 300tdi. It was the upper turbo host. The lower ones seems a lot more resilient because it doesn't have to do so much bending.

Can you hear a whizzing/whistling when revving over 2000rpm? This would suggest a turbo hose.

I also blocked out my EGR hosing this morning - I've only driven 10 miles or so since but it seems to be a lot more responsive and no longer lurches when slowing from 3mph to 1mph (when you're in a queue and really can't be arsed using the clutch but need to virtually stop) so I'm guessing the engine is breathing a lot better now.

If the hoses are ok, It's also worth checking that the fuelling and/or turbo boost have not been messed with. It's quite common for people to turn the fuelling up in the belief that in it will improve performance, but unless there is reason to do so it will usually actually slow you down. The turbo boot needs to be matched to the air temperature/volume to be optimum as well. Also, there's no harm in giving the intercoler a good clean out......

Richard

Richard

I can, on mine, hear a turbo whistle, only quiet but as the 200 did it too I assumed it was normal. I have indeed carefully twiddled with fuelling and have improved performance considerably. Richard is quite right, overtweaking will cause a performance loss and too much smoke. Having tweaked the 200 very successfully I know what a 2.5 litre engine of this type should be capable of, the increase in boost pressure from the 200 to the 300 should compensate for the increase in weight and performance ought to be at least similar. But it isn't. The engine is not willing and only starts to become so after many miles of driving when it smoothes out and starts to pull nicely.

I will be checking the hoses in greater detail although a cursory inspection hasn't revealed anything. I may try bypassing the intercooler to see if there's a leak in that.

I'll report back in due course. TonyB

is it worth removing the egr valve assembly?

Can you give me someinstructions/diagramsfor tweaking the turbo?

Thanks,

David

okay, I ordered a new intercooler hose and egr blanking plate.

I will remove the egr assembly this weekend and clean out the intercooler. A three hour soak in paraffin should do it.

On or around Wed, 14 Feb 2007 21:16:51 -0000, "TonyB" enlightened us thusly:

Check the pump-and-valve timing. What I did on our 300 TDi, which is now elsewhere, was to set the timing per book and then advance the pump timing "a few" degrees. Make sure you advance it rather than retard it and don't over do it. ISTR leaving the locking pin in the pump, removing the other(s), loosening the pump pulley and winding the engine back about 3 degrees worth, then tighten the pump pulley again. summat like that. reverse the engine compared to the pump is the same as moving the pump forward WRT the engine...

made for better pick-up off-idle, among other things. As with the fuelling, go too far and it'll lose power and sound like a bag of nails.

The tractor pulling boys do this; I've seen one which was so advanced as to pre-ignite and stall the starter motor, making it difficult to start. I think they do this to get maximum burn time at full overboosted overfuelled power. About as ungreen as you can get, pulling-tractors, but immense fun to watch.

On or around Wed, 14 Feb 2007 22:20:33 -0000, "tiscali" enlightened us thusly:

yeah, I can: "don't".

Unless you know for certain that the turbo is wrong, leave it be and sort everything else first.

The EGR can be blanked off neatly with a 2p coin in the pipe joint.

By all means, if you have access to a boost gauge, check the boost and see if it's to spec. But going above standard boost leads to big problems, and to get goo results you need an uprated intercooler, from my understanding.

turn it up too much and you can melt pistons and other not-nice stuff.

"Austin Shackles" wrote in message news: snipped-for-privacy@4ax.com...

Think I'll leave the tweaking to people with the appropriate gauges!

But I will remove the egr and clean out the intercooler.

Is it possible to clean the turbo?

There's very little to benefit from cleaning. Just oil/soot off the blades. There's also the risk that if you don't do a proper job and leave the rotating assembly out of balance you could be worse off than had you done nothing.

Forget the idea!

okay thanks! bottle of slick in the fuel tank should deal with the rest I guess.

At 100,000 RPM plus, thats very sound advice.

Steve

overfuelled

Thanks Austin, It certainly feels like the timing is out a bit. I'm not too familiar with the bits you mention so I'll be doing a lot of research before I get the spanners out on that one. Better pick up off idle would be great, funny enough it's worse in the evening after work than it is when cold first thing. Havinf said that, the morning start is on the flat and the evening start is uphills, that's when it really belches smoke. 2 miles later and it's sweet again.

Any idea what the throttle position sensor does? ( Apart from sensing the position of the throttle of course ;-) )

TonyB