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help! heres a log i think my turbo's had it!

1361 Views 15 Replies 3 Participants Last post by  aham_uk
here's the log

Engine speedSpec. intake press.Actual intake press.D.cycle MAP
/min mbar mbar %


sorry can someone make this in to a graph for me?

it will be much appreciated


log graph
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sorry! having problems posting graph
get a link to the picture (direct link) and stick it in [ img] [ /img] tags...w.ithout a space
o.k. i'll try.

i've manage to post up the excel info
did it posted graph now

thanks for your help chris.
Looks pretty good from what the specified and actual are.

Im not too good with the diesels though.

Whats the problems you experiencing?
What's your car doing to make you think you have a problem.
It's clear that it's capable of boosting to 2.1 bar so it's doing what it should but there is a definate fault with the turbo not spoiling down in a controlled mannor. As the duty cycle gets upto the higher % the pressure should drop away and at 90% it should be really dropping like a stone.
I would say your car has the start of sticky vanes. Take it for a drive, get the engine upto temperature then hold the car in 2nd/3rd whilst driving at 4500 rpm for 15-20 seconds. Afterwards do the log again.
O.k. i'll give that a go.

The problems i'm experiencing is lack off power and whissling turbo as it spoils up but it isn't the normal whissling sound.

And also when the EGR valve cuts out it whissles like it does when it spoiling up at idle. i've change the two EGR valve gaskets the ones between the exhaust manifold and EGR but still the same.

it Sounds possibly like a split pipe but all the boost pipes seem fine and i've changed all the vacuum pipes and N75 valve.

If you had a blown pipe you would not get the readings anywhere near this. If the vacuum pipes had failed you would get random boost not almost constant or if it's off you would not get any boost.

It could be a faulty N75 Valve but this is unlikely since it boosts up well and appears to work at higher revs.

When the vanes coke up, they cause sticking (sticky vanes) which the car fights to compensate for, making your car feel like it's struggling.

Giving the car the hot blast will clear some of the coke out of the vanes which can free the turbo up again, if not you wiggle the turbo actuator rod until its free moving.

As a test for you, remove the top vacuum hose from the EGR and plug it fully with a golf tee or bolt (don't run it with this pipe open to the world or it will put a warning light on. Your car will run smoother.
o.k. i'll give that a go to.

hi aham_uk

I tryed what you suggested get it up to temperature and hold at 4500rpm it in 2nd and 3rd for a couple of seconds. And i also changed the fuel filter and put a drop of forte diesel treatment in with the fuel before i did it. It does seem a little better but havn't had time to do another log yet. I have also sauced a proper EGR delete pipe from a friend just need to put on.

thanks for your help so far.

Driving for economy causes the turbo to coke up. A blast per week clears this and improves over a few weeks.
i've now fitted egr delete and it feels ten times better and its better on fuel as said so i think its defently cured my problem[<:eek:)] and thanks for your help its been very much appreciated[:D]

i've now fitted egr delete and it feels ten times better and its better on fuel as said so i think its defently cured my problem[<:eek:)] and thanks for your help its been very much appreciated[:D]

I'm glad your fixed, it should get better but once a week blast the soot build up and youll not have any more problems.
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