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Hi guys,
my 110 hdi drives great most of the time but over the last couple of weeks with no warning
every now and then when I go to accelerate it just slowly picks up, which can be dangerous when you are expecting a surge of power!
then a mile up the road its ok again?
Its is as though the turbo has not kicked in at 1500 rpm
Is it the turbo failing or an actuator if there is a such thing ??????
Any ideas

just thought I would say there is no fault codes showing up on my cheap code reader

Sounds like a vacuum leak on the pipe that feeds the turbo, or elsewhere in the system which is making the turbo vanes/wastegate slower to react....

This would normally put the engine management light on though..

Is your EGR blanked? If not you can disable it so it's permanently closed ( a sticky valve will stay open so not all of your exhaust pressure is feeding the turbo to increase the boost, it's diverted back into the engine bypassing the turbo instead)

Thanks, The egr is blanked off ,will check the vacuum pipes.

Do the brakes work well? If the servo is leaking it will diminish the amount of vacuum available.

Peter

the brakes are working well

Hi there, have you checked the maf (air flow meter) sensor? Could be worth unplugging it to see if the car drives normally. When plugged back in if the problem comes back... your maf could be on its way out.
Hope this helps mate.

Just got the car through its Mot ! only needed a couple of brake pipes on the rear and a front anti-roll bar joint £100
will get the chance to check a few things this weekend

egr blanked
brakes are great
will start with vac pressure???

I tend to start with the easy stuff first...

Replacement vacuum pipes will be about £5 for silicon ones from eBay - may not fix your issue but it's piece of mind for the future.

While you are swapping the pipes ( just do one at a time ) check the restrictor on the servo - just press in the two grey tabs and it will slide off. There are pin holes that restrict the amount of vacuum being drawn down the pipes - easy to get blocked.

As your EGR is blanked, swap the solenoids on the bulkhead round - only 10mm nuts - this may eliminate the solenoid as being faulty.

As suggested, the MAF can be unplugged to determine if it's worn - replacement ones are around £70 from local motor factors, cheaper on eBay but not always the correct quality. To be fair if you can afford a new MAF then I would suggest it - only as it I feel it should be changed every few years to keep everything in order.

Lastly, as a bit of a curve ball, check to see if your rear calipers are sticking - quite common and will certainly drag the car down when you are expecting a bit more ooomph.

Good luck - please post up your findings.

Thanks for the info:
did some tests with my vac gauge before reading your post:
vac pressure is 60+
took reading feeding turbo and constant 60 at tick-over and only reduces to about 40ish after reving it a bit and letting of the revs, is this how it is supposed to work ???
did notice bracket holding the 3 solenoids had broken , so had to tie-wrap it up
The problem seems to be getting more regular, so needs sorting !
will try and source some new vac pipe and try your checks

cheers

ps :
I put new calipers on the rear last year

ps2: fitted new MAF 02/2018

I think I have located the problem,
the vac pipe feeding the turbo solenoid seems to be not sealing at the vac pump end ! did a temp fix till new vac pipe comes from ebay and the turbo loss only happened once all week going to work
when I said my vac gauge was reading 60+, that equates to 500 mm-Hg, the manual says MIN 500 mm-Hg so ok

if weather ok next weekend will replace vac pipe, pipe should arrive on 21st fri

Sounds good, well done for spotting it.

If I remember correctly, I was getting 700mg of vacuum on tickover - increasing with revs but if the gauge is plumbed in after the solenoid, the reading will go down - this is how the system works, vacuum is reduced via the solenoid to move the corresponding parts...

I would be tempted to remove the 2 way restrictor from the servo, and fit it to the vacuum pump instead ( the solid pipe direct to the servo, the restricted outlet direct to the turbo solenoid ) - then you will have a better vacuum supply to the turbo without compromising the brakes..

Good luck.