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Td5 Sluggish - Poor Acceleration - Nanocom Readings


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Hi all - my new (to me) 1999 Td5 Disco ES is very lovely in every way except for a lack of 'balls' or 'guts'.

It starts on the button with very little smoke, runs smoothly and generally seems happy except that acceleration is what I would describe as pedestrian.

Pulling away is painfully slow at times and it struggles to hold more than 70mph on the motorway. On some motorway hills it will slow to below 50mph with my foot flat to the floor.

Things that have been checked/done:

- MAF sensor unplugged, no noticeable change. (Reads 4.4 g/hr on Nanocom).
- MAP removed and cleaned, was quite black and gungey - very small improvement.
- AAP removed and cleaned, wasn't dirty, no change.
- Injector harness changed - no improvement.
- Checked for oil at red ECU plug - very small amount, cleaned with contact cleaner twice. No change.
- Checked intercooler pipes - they seem 'soft' compared to old Tdi ones but are sound with no splits or leaks.
- Checked turbo impeller for play - very little, normal amount.
- No EGR present (would a 99 have had one?)
- Will rev up to 4,750rpm/governer cleanly (perhaps a little reluctant but does get there).
- Turbo wastegate is free.

With my newly acquired Nanocom I have ascertained that the correct level of ambient air pressure (~100kPA) and manifold turbo pressure (~210kPA) are being registered, and the turbo wastegate actuator begins to open at around 160-180kPA with a reading of between 30-40%.

The only recurring error I get is 'EGR valve stuck open' which I presume has something to do with it being removed?

Any suggestions as to what I can try now? I'm at a loss really and would be overjoyed to be able to sort this and get it going properly!! tongue.gif

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Certainly worth checking out the EGR has been done properly, but with loss of power like that the next thing I would do is look at the fuel pump pressure. It can drop away and not show as a fault on the electronics, you need to plumb in a sensor at the back of the engine where the fuel temp (?) sensor goes, it should be 58psi all the time, if it drops under load (or with the engine running) then the pump is on its way out. New fuel pump time.

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Check that the intercooler isn't clogged.

Someone I know with a TD5 he retro-fitted into an old Rangie had terrible performance problems. The intercooler came from a different engine to the one he had fitted - and it turned out to be full of black, oily, gritty snot and sludge. Pulling the intercooler, filling it with heating-oil, then spending several days giving it a good shake every few hours followed by draining out all the nasties and steaming the thing through - restored full performance.

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