[Owain]

I recently bought a diesel Corsa 1.7 CDTI from a second hand dealer in wales. After the first 500 miles I have noticed the following symptoms;

1) On start-up (cold start) the car struggles to pull in second gear between 1-2k RPM

2) When motorway driving, the car will sometimes slip into limp mode and will not surpass 3k RPM. This can be quite dangerous is moving to overtake.

I have searched the internet relentlessly for a solution to this issues have been identified as one of 3 potential things;

1) Faulty MAF sensor
- Bought electrical contact cleaner, and then used an OBD sensor to collect data and plot air mass flow vs rpm. This correlated almost exactly.. so I doubt this is the issue.


2) Faulty EGR value
- This was replaced before I purchased the car, so I’m hoping this is not the issue – but I have read that blanking the EGR can improve performance in the scenario I have on a cold start.


3) Cracked hose tubing between the turbo & intercooler
In respect of issue 3, I found that the connection between the turbo manifold (component 48) and the hose leading to the intercooler (component 32) appeared not to create a perfect seal when revving.

http://imgur.com/a/EHEZ3[/IMG]

This joint is not air tight under acceleration, and component 32 moves back and forwards roughly 1-3mm. Should this connection have zero give, or is what I have in the video below normal?

I have seen a video online that states that once component 32 it removed from 48 - its not possible to reattach it with a successful seal. Video below - is this true?

Has anyone had any experience with this? How would I go about tightening the seal.. or do I need to replace the whole of component 32?

Any help is greatly appreciated.

 

[Koicarpkeeper]

Your image is not loading so not possible to see what you are referencing.

Your video sounds like you have a loss if boost.
When you took your live data did you not retrieve any fault codes?
What equipment are you using for the diagnosis?
If it is dropping into limp there should be fault codes set.

 

[Owain]

Hi, This is the diagram I tried to include in my post - http://imgur.com/a/EHEZ3

Before I bought the car, all fault codes had been wiped - and no new ones have appeared. I'm going to go back to the car now, connect, and check just to make sure.

 

[Koicarpkeeper]

My 32 and 48 have been disconnected a few times with no issues.

 

[Owain]

How do you remove the clip which holds these two components together? Its not like one I have seen before.

On your cars.. is this connection at all loose, or are they fastened tightly together?

Re-checked this - There are also no fault codes on the car http://imgur.com/a/j1Iq8

 

[Koicarpkeeper]

Are you using that crappy Torque app?
If so that is why you are not picking up the faults correctly.
Go buy a decent code reader
http://www.ebay.co.uk/itm/162252954795?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

Torque is fine for the basics - I have a dongle sat in my glovebox but I also have an OpCom and a VauxCom sat next to it for when I want to do some real diagnosis.

 

[Koicarpkeeper]

My top connection is a jubilee clip, not sure about the bottom one because I have never split that one. Neither have any movement - that is your issue you are loosing pressure (boost).

 

[Owain]

Its a OBD Auto Doctor app with a wifi dongle from eBay.. I expect you are right, and it won't pick up Vaux specific codes.

I have just been out and taken more photos of the clip that I have at the engine end of the hose;
http://imgur.com/a/9Hcgf
http://imgur.com/a/TS0G2
http://imgur.com/a/DWjiY
http://imgur.com/a/Euicy

It looks like its the same fitting as the pipe in the second video in my first post above.. but I've got no clue how to get it off without damaging it. It doesn't look like a standard jubilee clip. Any ideas?

 

[andyl]

The pipe clip has a steel clip going around it , the ends of the clip are inside the black plastic, the other part of the clip that needs prising out is out of view due to the way the hose is fitted, its the same type of clip as the one in the first picture of this link, you just need to prise the metal clip out and pull the hose off.....http://www.ebay.co.uk/itm/like/3218...=1006567&device=c&campaignid=707291931&crdt=0

 

[Owain]

So should I remove the black plastic in order to release the clip.. or should I move it forward and back to try and prise it off?

I'm wondering whether its worth replacing this part with an equivalent from a scrap yard.. just incase it has damaged which is only really visible during loading. It seems strange that the clip shown in my video moves around so much when just revving the engine?! Maybe I can mess around with the clip once I have got it off in order to re-fit it a bit tighter.

 

[Owain]

So I took the car to a parts dealer, and they had a look at the top fitting of that hose, and said that it was fine. They suggested it could be an issue with the turbo wastegate. I am getting no ECU error codes relating to turbo boost, but I checked this today.. and the actuator opens and closes fine when revving.

I did notice the following actuator does not appear to move at all.. does anyone know what this relates to / what its function is? From what I can see the turbo is fitted on the underside of the front of the engine - and has nothing to do with this actuator.

http://imgur.com/a/at3AK
http://imgur.com/a/oOmkl

 

[andyl]

Thats the egr cooler bypass actuator.
Do you have a good vacuum at the turbo actuator and do you have the ability to record live data.

 

[Owain]

Thats the egr cooler bypass actuator.
Do you have a good vacuum at the turbo actuator and do you have the ability to record live data.

Ah ok, so you wouldn't expect this to function until the car has been running for a while.

The turbo actuator moved about 1cm at 2k RPM, and about 2cm at 3k RPM - whilst revving the car out of gear. I have got an Auto Doctor app.. I will go and check the variables it can measure now.

Thank you for your help on Christmas eve!