2.5 TD No Boost - Wastegate stuck?

[dark legend]

Coming home from racing today, pulling along quite happily, the engine note suddenly changed (best way to describe it is probably it sounded more diesely) and the van is now down on power. It just went from full power to nothing in a second, not a gradual decline, it now struggles harder than the wheezy old 70ps DI it replaced.

When I pulled over and got the Mrs to rev it, there was no Turbo whistle.

No faults up on the EPIC, just no power and i'm thinking no boost by the feel of it. Temps stayed happy and there was plenty of oil, so I limped home.

I'm hoping it's a stuck wastegate actuator, but then would it not stick at a position giving some boost? Or perhaps a failed diaphragm inside stopping it from working, but would that overboost?

I don't want to consider the fact that the Turbo is nailed!

I'll get the grille and air intake off tomorrow so I can have a good look at the turbo and see if it's spinning up at all. I've got a boost gauge for it which isn't fitted yet, may help with the diagnostics..

Anyone got any suggestions, other than knackered turbo (fingers in ears, i'm not listening!!) Also, shouldn't the EPIC have thrown up a fault light for something as major as that?

What a great day, the racecar engine seized up soild so needs a full rebuild and then the camper dies towing it on the way home

[jacka]

hi the wastgate arm pin came of my cosworth once had no power i slid it back on and used a panel pin sounds same problem cheers ,jacka

[psv-hgv-flt]

egr stuck open.?? take the air box off and see how turbo sounds

[AndyG]

So you have the "engine" light that works in the dash binnacle when you turn on ign. and goes out when the engine's running

Could the timing belt have slipped

[LSi]

If the engine note changed, could you have cracked the exhaust manifold?

If the exhaust gasses are escaping before the turbo it won't spool up as much.

[alanwh]

Sounds like it's blown an induction pipe off

[dark legend]

So you have the "engine" light that works in the dash binnacle when you turn on ign. and goes out when the engine's running

Could the timing belt have slipped

The ECU light comes on with ignition and extinguishes a couple of seconds after starting.

Still running the old belt which I re-fitted due to a long time getting the replacement, so that could be an option.

If the engine note changed, could you have cracked the exhaust manifold?

If the exhaust gasses are escaping before the turbo it won't spool up as much.

Worth a check -thanks..

Sounds like it's blown an induction pipe off

Didn't look that carefully at the top end actually, that'd be a nice explanation, or a split.. But wouldn't the turbo still spool up? I guess you need the boost to generate the boost though? so perhaps not.

Fingers crossed it's a simple explanation!

[dark legend]

Perhaps the boost sensing electronic bit has packed in? would still expect a fault light mind you...

[mrepson]

i would check the boost pipe clips or the pipes for splits .as when 1 of my pipes came off,it was dead slow,

[billybun]

Mine came apart the bolts snapped as i was driving along,and even snapped where the bracket bolts to the block,the only thing holding it on was the oilfeed pipe, the same happened to my mate Teds td ...

[redeemer]

Did it changed smoke colour, or intensity?
Maybe a sliped belt,
But once when I fitted my turbo to a 70ps di, my home made induction pipe blown off, even though it was thightened by a jubilee clip. I noted that something was wrong , when it came to a hill, but because I have the boost gauge connected to the wastegate acyuator pipe, it still marked 0.6 max boost.
For worn turbo, shouldn't the intake and exahust be full of oil??
goodluck!

[dark legend]

Had a play with it today, with the following results:

Turbo spins freely by hand, no significant play.
Turbo spins up with engine running, changes speed with revs.
Turbo whistle can be heard when revving under load.
Boost gauge connected - turbo putting out 0.7bar at 3500 revs loaded up hill.
When disconnecting the electronic boost sensor, EPIC fault light comes on and stays on. Re-connect, it goes back out.

All hoses look intact, breathing a bit of oil through the rocker breather, oil on the inlet blades, but nothing bad.

So i'm concluding the Turbo is fine, it's boosting (boost gauge tee'd into the ECU's electronic boost sensor line)

It's still flat as fck however, so i'm guessing the pump isn't putting in the required fuel for some reason, boost sensor is connected, and EPIC fault comes up if disconnected, doesn't mean it's working though... Would you expect smoke of any colour if it was lean? OR the slipped belt which is the next port of call...

Only other suspects are the EGR side of things, but i'm not sure how it would affect. I'll just dig out a picture and then explain my findings on that section in another post...

[dark legend]

Right, one possible culprit is this:



Can anyone explain what it's for? It sits on the plate next to the boost sensor and is connected to the airbox, the EGR flap actuator and the other pipe marked ???? is not connected to anything but sits down by the injection pump. Should this line be connected to something or is it a bleed / drain?

Also the EGR flap actuator appears to be kaput as i sucked on the pipe and it was pulling a bit then passing, certainly no movement on the actuator arm.

It looks like that flap closes to let more exhaust gas through though, so being knakered shouldn't affect the power? Is this open ended pipe bleeding pressure off something it shouldn't though?

I'm guessing the little black bit is some sort of solenoid valve that opens to put a vacuum onto the egr actuator and pull it open, but does that vacuum come from the airbox or whatever the other pipe should be connected to?

[trans9]

Turbo whistle can be heard when revving under load. quote

I have been told; if you hear turbo whistle, in any case, it`s broken or assembled wrong

Exhaust side of tbo, is craked, when/if it whistle.

[Guy88]

that pipe goes to the brake servo vaccuum line and is used to operate the EGR, just T's into it

May affect performance if the ECU is confussed