Thread: Loss of power and economy - tdi auto Disco

Originally Posted by goldey

Camel Landy, where is this plunger pin you're referring to?? Is this something a garden variety home mechanic can check????

Yep, it's pretty easy for a DIY mechanic. This is one of the write-ups I did a while ago... Clicky...

Originally Posted by goldey

And on the subject of turbo hoses, I recognise the fact that mine need replacing as the originals are soft as butter (that's warm butter) especially the 90 degree elbow off the turbo housing itself.

The ones you need to be wary about are the ones which go from the air intake through to the turbo. These are the ones that are under -ve pressure and have the potential for collapsing while the turbo is 'sucking' the air through.

Originally Posted by goldey

A final question for you all, Can the timing (pump and engine) be checked without removing the timing belt cover and all other associated stuff? In case it has slipped from when the LR mechanic did it.

Yes, it can be checked... Basically, there's a timing point on the flywheel & fuel pump which can be checked to make sure it's all still in sync. However, you're probably going to need the special tools...

HTH

M

Pump timing is easy to check, you just remove the air conditioning tensioner pulley from the front of the timing cover. It acts as a window to the pump pulley adjusters and timing pin hole.
Slightly retarded timing can make the whole engine a bit doughy, and it can be the difference between the pin being tight and easy to push into the aligned holes.

Re the hoses, while the OE ones become oil soaked and spongy, they aren't likely to cause a power loss unless they have started to de-laminate internally, which can be reasonably common.

It may pay to run some good injector cleaner like Redline RL2 through your next tank of fuel. A poor spray pattern can make any diesel run like crap.

Originally Posted by justinc

If the belt is due to be replaced, make sure the pump plunger lift is set to 1.6mm. Factory spec is 1.54mm, believe it or not that .06mm makes a lot of difference. This is a must do for all auto Tdi's.

JC

Justin, what is the pump plunger lift? Is it a job where the injector pump needs to come out ?

Thks Rick130 and Camel Landy.

Anybody in the Newcastle Hunter area have the special timing tools?? that I can borrow?

Cheers

Goldey

Originally Posted by pawl

Justin, what is the pump plunger lift? Is it a job where the injector pump needs to come out ?

Sounds as tho you you could do with a manual ..... order a RAVE CD from this site // Try this link

http://www.davesitshop.com/davesitsh...iewCat&catId=1

Pawl,
Plunger lift adjustment basically advances the pump timing, the effect is rather like a petrol engine ignition timing advancement really.
Has to be done with the pump in situ and timing belt attached etc, and is measured through the back of the pump body on the Bosch pump using a special adapter tool and a dial indicator.

Adjusting is a bit fiddly, even the slightest movement gives quite large variations on the DI, and makes the job frustrating sometimes. The result is worth it though.

JC

Thanks Justin,
Bugger, need a special adapter tool and it sounds like it may not be so simple for a DIY.

A stall check is the easiest and cruelest test you can put an auto to....

Start it up and take it for a very short drive just enough to get the engine warmed up a little and the trans happy.

make sure you lock the CDL if you have one.

pull up the parkbrake as hard as you can.

put it in D for do hope this doesnt break the transmission.

mash the brake pedal into the floor.

floor the noisey pedal.... while holding the brakes on hard

the engine should rev up to about 2 grand maybe a bit more.

Dont do it for more than 5 or 6 seconds as that will bugger something.

if the engine spins freely past the nominated RPMS something isnt holding correctly in the trans somewhere.

if it doesnt rev then its not making full power.

Try this BEFORE you start doing plunger lift mods and everything else that makes the engine make more power as that will throw the stall test RPMs out.

If you dont have a tacho for your vehicle do the test anyway and then ask someone with the same setup vehicle as you to do it as well and give it a by ear.