Thread: Tdi turbo hoses replaced - lack of power still exists. Help?

Will do.

Yeah injector pump has been "tweaked" a fair while ago for extra power (ironic eh, but it did work for a while!). Smokes sometimes changing gears etc as a esult of thetweak, but nothing truly excessive to be concerned about.

Hmmmm, well the injector pump settings shouldn't just "change" so like you suggested first, check the intercooler hoses.

You could also cast your eye over the boost compensator and waste gate actuator hoses. Make sure they haven't detached, split, burnt through on the exhaust manifold, etc. This is more likely to cause loss of boost/higher end lack of power, and not specifically when cold, but worth a look while you're at it .


James.

any diagram showing what ones those hoses are.

It's pretty easy to spot them. Start at the large 2 inch-ish steel tube between the turbo and the intercooler (your rubber hoses either end of it). On top of that there's a small hose (approx 1/4") coming off. Trace that to the T-piece. From here it splits, one going to the wastegate actuator underneath the exhaust manifold, and the other around the back of the block to the top of the injector pump. Check that all of those 1/4" hoses are connected, split free, etc, etc.


James.

When were you tappet clearances last checked?

I notice it when mine need adjusting. As you said low down torque is affected, especially when cold

Most noticable was when I had a lash cap let go and one was way out

The book says every 20,000km I do mine every 10,000

my hoses are no good, they made their way under something heavy and now have a cross section that might feed an RC nitro engine.

Well I finally did the hoses. Wasn't too hard a job.... until I got to the bottom one. Talk about inacessible ! What a bugger of a thing to work on. Anyway finally got it done and problem with power is..., unchanged.

Where to look next? I really want to get this fixed asap.

So, let's just revisit the symptoms again - is it bottom end power, top end power, or just generally a "lack of power"? Are you making boost? You wouldn't happen to have a boost gauge fitted would you? Can you hear the turbo spooling up?

You could check the function of the boost compensator in the injector pump. On top of the injector pump, where the small hose from the intercooler pipe attaches, there are four screws (could be allen head or flat blade). Undo them and very carefully lift the top. The diaphragm underneath may be slightly stuck to it, so don't pull it all of the way up, and don't rotate the top while it's attached to the diaphragm. You'll need to separate it carefully. I use a Stanley knife, but you have to be really, really careful not to score, or puncture the diphragm, or score the mating surfaces of the injector pump. As soon as you have the lid off, mark the position of the diaphragm in relation to the pump body with a pen. It rotates to change the amount of fuel delivered as boost changes. This is very critical in the tuning so mark it, and then preferably don't rotate it. Now push gently directly down on the metal centre. It has a spring under it so it should slide down and spring back up freely.

Having said all of this, if you're not confident it's probably best that you don't do it. Trying to think what else to check . Did this suddenly start happening?


James.