Altitude is not a problem here in North Wales. I am probably about 50ft above sea level! Are those tempratures internal? I work in the Aluminium industry and that is close to melting point!

The thermocouple is poking into the exhaust manifold quite close to no 1 valve. You are right, those temps are high. If you run over about 750c for long it is bye-bye engine. The local diesel tuners reckon anything over 725 is pushing it.
I can't tell you what the piston head temp is though. Aren't pistons made of high-silicon alloy or something like that?

ps In Wales you also get free water injection, not the dry air we have here

Yes very damp and humid here all year round. The temp gauge is plenty accurate enough!

Well, I took the EGR off and the pipe off that the EGR feeds into, the one thats about 55mm in diameter and goes between the intercooler and the intake manifold. It was full of orrible black slimy gunge (what is it? its oily which is a worry), anyway, I replaced it with an 8" length of scaffold tube which I had sprayed black and it looks the part. However, would I be better off getting a length of the correct diameter hose and going straight to the intake from the intercooler with it as I have dropped to the internal diameter of the scaff tube which I reckon can only be 40mm at best. Will this have a negative effect?

revjames said:

Well, I took the EGR off and the pipe off that the EGR feeds into, the one thats about 55mm in diameter and goes between the intercooler and the intake manifold. It was full of orrible black slimy gunge (what is it? its oily which is a worry), anyway, I replaced it with an 8" length of scaffold tube which I had sprayed black and it looks the part. However, would I be better off getting a length of the correct diameter hose and going straight to the intake from the intercooler with it as I have dropped to the internal diameter of the scaff tube which I reckon can only be 40mm at best. Will this have a negative effect?

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Nice one revjames!
That black crap is a mixture of oil from your engine breather that sticks to the soot from the exhaust gases to form "Marmite" yep that's where it comes from

You can get silicon replacement pipes of flea-Bay for about a tenner.

If you pay to have engine upgrade fitted, a metal pipe is installed where you have put scaffolding pipe. [ Allbeit the correct diameter]

The power upgrade I was offered included cutting out the cat, removing the EGR, installing a K&N filter and tweaking the pump. £200. The only thing left is the filter and the pump adjustment.

revjames said:

The power upgrade I was offered included cutting out the cat, removing the EGR, installing a K&N filter and tweaking the pump. £200. The only thing left is the filter and the pump adjustment.

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And a chip which will give you even more ooooomph

ooomph improved already. I have noticed a distinct improvement on hills and particularly when you get above 1500rpm it really starts going.

Have visited my mate this aft who has upgrade fitted by twisted Performance, list is, Chip, Intercooler, Turbo Pipes and Air Filter.

He has it fitted on S reg 300 Auto. Have had a drive and it is Scary, yes Scary. it just sets off and goes and goes, I would be scared of it blowing the engine up if it was mine.

I would go as far as to say it would be dangerous in the hands of an inexpirienced operator.

That does sound scary. To be honest, I am pleased with the performance and if I get better mpg with the egr and cat gone then I will leave the filter and pump settings.

Take your intercooler of and rinse with white spirit.this will have oily deposits in it from the egr.Also remove the inlet manifold and see the soot that is left in there from the egr,it can be cleaned by soaking overnight in parrafin then scrubbing out with a bottle brush.BUT YOU MUST DRY BOTH PARTS COMPLETELY BEFORE RE-FITTING,OR ENGINE WILL BE DAMAGED.
My manifold openings were 50% coked up with carbon,and it had only done 75000miles.If your impressed now see how it runs when youve done that.
Hope this helps

To add my $.02, I bought the 'EGR Blanking Plate Full Kit' from 'Phillipstuart33' on eBay. £9 inc P&P.
It's a plate, gasket and 2 (longer) bolts - with instructions. Delivery was next day.

The kit is actually designed to be inserted on the hose side of the EGR valve - leaving the valve in place.
I completely removed mine so used the new plate and gasket against the manifold (a la Difflock) but found even the existing bolts now slightly too long (or just not used to screwing in that bit further) so I used the metal gasket from the original to pack out a little.

I also bought a replacement top pipe from Allisport - again friendly, next day delivery but I was slightly taken back by the price - £50 for a hose. Bloody hell...

I soaked the bolts in WD40 the night before which was well worth it - by far the longest part was undoing them - grazed knuckles ahoy!
I left the valve's wiring and plug tucked in by the jack and sealed the now empty pipe hole on the nearby unit (?) with a bit of sealant.

Mine's a basic 97 manual 300tDi with about 128K. It wasn't blowing out smoke previously but did feel a little 'lumpy', particularly in the lower gears. When I removed the old top pipe there was an amount of thick black gloop, which took some cleaning - I advise gloves

I have noticed an immediate improvement in response - and not all that subtle like I thought it would be. Going through 1st and 2nd is definitely smoother and it pulls up hill much more evenly.
I've not had the Disco that long and have only ever measured the MPG over 50 miles, which returned about 23mpg. Not brilliant. I'll be interested to see what I get now - I'll do a more accurate reading over 200 miles next.

So, an easy job (I'm no mechanic) and an immediate benefit. Result

Now I want a new intercooler.........

Hi, has anyone any experience with this kit on ebay
eBay.co.uk: 300 TDI Discovery Alloy Intercooler Pipes (item 150111234937 end time 20-Apr-07 18:30:25 BST)

it seems fairly good value compared with 1 silicone hose costing £50

well not sure if its all down to the EGR but I have driven over 400 miles the last couple of days and returned an amazing 31mpg. Is this good? It wasnt all plain sailing. First there was an annoying whistle which developed into a throaty rasp as the gasket I placed under the blanking plate blew apart. This was because the bolts were too long and thus were not putting sufficient tension on the plate and gasket. A tub of exhaust paste, some washers and an allen key fixed the problem. I have heard legends of 36mpg with K&N filters and pump settings altered. We will see.

Well guys I got round to fitting my blanking plate today on my TD5. I got the plate in ok minus a few grazed knuckles but couldn't get one of the engine cover bolts out to get some measurements to fabricate a new intercooler pipe out of stainless so will sort that at a later date.
The main differences i've noticed is it has lost the lumpy tickover and the missfire syndrome at low revs, the flat spot has gone when you put your foot down on the motorways it now wants to go when you shove your foot down and find yourself backing off, I tried a hill by me that needed to come out of 5th to 4th but now It flew up in 5th no probs, will have to do a few more miles before I can get some fuel reports, all in all it was the best £9 i've spent and when I can get this bloody bolt out of the engine cover will replace the intercooler pipe with a nice shiny number.