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Discussion Starter · #1 ·
Hi

I have asked several times in someone could give advice on my turbo problem I have fitted a new turbo and the boost is all wrong it wouldnt acclerate but cruised ok Now i have adjusted it to what i think the old actuator is set to NOW it accelerates like a rocket but when it reaches 40/ 45 it dumps out on limp mode. Now its also smoking like a wreck. Before the turbo change it ran clean?

I belong to the Volvo owners club with my car and had problems with it -loads of members came forward and one guy drove 40 miles and worked thru the night with me to get my car sorted FOR A CUP OF TEA! NOW THAT IS AN OWNERS FORUM

PLEASE? I will be homeless shortly if I cant get the van running sweetly. I'll be living in a box under a bridge.
 

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Engine code? so we know what turbo is fitted..Altering the turbo actuator arm length or the stop screw can be a minefield without vcds and a pressure gauge on the exhaust manifold. These are nornally setup on a flow bench as a little adjustment can be a big pressure difference.
 

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Discussion Starter · #3 ·
Engine code? so we know what turbo is fitted..Altering the turbo actuator arm length or the stop screw can be a minefield without vcds and a pressure gauge on the exhaust manifold. These are nornally setup on a flow bench as a little adjustment can be a big pressure difference.
THANK YOU so much does that mean I have to strip out the turbo again?
the engine is the AXD 2.5 DIESEL
TURBO - GARRETT GT174

I cannot find ANY fault codes as the CANBUS is dead. So my OBD2 laptop wont work I havent tested it yet to see if theres 60 Ohms across the BUS and voltage to the high and low inputs.
 

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I cannot find ANY fault codes as the CANBUS is dead. So my OBD2 laptop wont work I havent tested it yet to see if theres 60 Ohms across the BUS and voltage to the high and low inputs.
What year is the van? I've been wrong about this before and been corrected, but I ~think~ that on the pre-facelift, the connection for diagnostics on the OBD port is K-line, not CANbus. The CAN gateway does the conversion from K-line to CANbus where needed.
 

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Discussion Starter · #5 · (Edited)
What year is the van? I've been wrong about this before and been corrected, but I ~think~ that on the pre-facelift, the connection for diagnostics on the OBD port is K-line, not CANbus. The CAN gateway does the conversion from K-line to CANbus where needed.
its a 2005.
Aaah so then would an OBD2 NOT WORK do I need another type of reader? The error code is CANBUS NOT VISIBLE? Or is that a comms/ conversion fault?

Is it possible Ive lost an EOL resistor? Can the BUS be repaired as It would help with fault finding please?

thanks
 

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Discussion Starter · #6 ·
Engine code? so we know what turbo is fitted..Altering the turbo actuator arm length or the stop screw can be a minefield without vcds and a pressure gauge on the exhaust manifold. These are nornally setup on a flow bench as a little adjustment can be a big pressure difference.
A) Who would be able to do this?
B) Anyone in Hants?
C) have i got to strip the whole thing again to get the turbo on a test bench😩
 

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The error code is CANBUS NOT VISIBLE?
What is generating that error code? What is the fault code number?

What you need to establish is whether the error is being generated by a control module in the van, or by the code reader itself.

If you have a major problem with, for example, the drivetrain CAN network, you should expect to see dash lights on, and multiple things not working quite as they should. For example, the ABS controller would not be able to talk to the ECU - and it won't like that at all.
 

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Discussion Starter · #8 ·
What is generating that error code? What is the fault code number?

What you need to establish is whether the error is being generated by a control module in the van, or by the code reader itself.

If you have a major problem with, for example, the drivetrain CAN network, you should expect to see dash lights on, and multiple things not working quite as they should. For example, the ABS controller would not be able to talk to the ECU - and it won't like that at all.
No idea I literally cant access the OBD2 system its dead. I working like a blind man in a dark room here trying to solve this turbo fault with NO CODES. I must try and get the CANBUS back to life somehow?
 

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It's just as Triffic says, your van doesn't use CAN for engine diagnostics so your scanner is probably just telling you that. It should be able to communicate with the engine via the k-line but if your scanner is simply trying to use EOBD to communicate that won't work either because the old vans weren't EOBD compliant.

I'm sorry but I can't help with the turbo because I have never fitted one that didn't come fully and correctly set up. I know tuners and mappers do this (with the help of expensive equipment) but I wouldn't risk meddling because that voids the warranty. I don't understand why didn't you just send it back if it didn't work? I don't think diagnostics will help much because all you will see is overboost codes and the live data showing a big overshoot of the specified MAP values. You might be able to tinker it better but really it needs setting up on a bench as Festa says.

It's worth checking to be sure you have all the small N75 vacuum pipes the correct way round so you haven't accidentally created a new problem! Good luck! :)
 

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Did you buy a new complete turbo unit or just a core and fit yourself? Where did it come from?

What scanner or software are you trying to gain codes with, does it show live data?

Sent from my SM-A528B using Tapatalk
 

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Discussion Starter · #11 ·
It's just as Triffic says, your van doesn't use CAN for engine diagnostics so your scanner is probably just telling you that. It should be able to communicate with the engine via the k-line but if your scanner is simply trying to use EOBD to communicate that won't work either because the old vans weren't EOBD compliant.

I'm sorry but I can't help with the turbo because I have never fitted one that didn't come fully and correctly set up. I know tuners and mappers do this (with the help of expensive equipment) but I wouldn't risk meddling because that voids the warranty. I don't understand why didn't you just send it back if it didn't work? I don't think diagnostics will help much because all you will see is overboost codes and the live data showing a big overshoot of the specified MAP values. You might be able to tinker it better but really it needs setting up on a bench as Festa says.

It's worth checking to be sure you have all the small N75 vacuum pipes the correct way round so you haven't accidentally created a new problem! Good luck! :)

cheers mate I think its time to cut my losses and sell it. I'm rapidly NOT wanting a VW as they arent as reliable as I thought!

Its really dumped me in the **** I have been given notice to move out of my rented room as they are moving so I cant even strip the turbo out and return it. Ive got to live in the thing. Well its going to be 40MPH everywhere followed by smoke! I wil have nowhere to even get it up on ramps again🤷‍♂️
 

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Discussion Starter · #12 · (Edited)
Did you buy a new complete turbo unit or just a core and fit yourself? Where did it come from?

What scanner or software are you trying to gain codes with, does it show live data?

Sent from my SM-A528B using Tapatalk
I fitted a new CHRA core (which I have done several times on Volvos without a hitch) plus a new actuator and VNT ring. Set it up on the bench IDENTICAL to the old actuator length and setting. Only thing Ive NOT done is a vacuum set up on it to see if its hitting the stop. All adjustments on the actuator have to be done leaning over the block with a mirror and a 10mm spanner. I then get 2 goes to see it ifs right before the turbo gets too hot to be near. Got the parts from Turbo Rebuilds and London Turbos the 2 best suppliers.

I couldnt afford a complete turbo so mistakenly I thought I could save money this way HAHHAHA its going to cost me a LOT more than a turbo now to sort it what a retard I am! That engine is such a pig to work on too. I worked on everything from Minis to V24 Caterpillars NOTHING as awkward as an AXD. I replaced the alternator as well as the old one was fried thats was also a job you have to virtually dismantle the WHOLE FRONT END to get to

I got the best scanner I could find actually tried 3 - mates brought over and same result no codes.

Pretty likely I will sell it im out of options/ money/ workspace/ home with a dead useless vehicle.
 

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Hi, if I were you I’d buy a cheap boost gauge and see if your getting anything and work from there ( makes adjustment simple ). It sounds like you haven’t put it together correctly so you might want to get a rebuilt turbo and do a straight swap, 2004/2005 AXD ran KKK turbo so I’m not sure you have the correct one fitted ( can’t be sure on that ) make sure you have connected the actuator pipe correctly and that it doesn’t have any holes or perforations, same goes for the oil gasket as they can slip out of line when you fit them. Good luck
 

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Discussion Starter · #14 ·
Hi

Thanks yes Ive ordered a new warranted turbo! Its all balanced and set up. They will get my old one back. Not sure about this KKK turbo?
Mine is a Garrett 720325 so it will be a straight one for one swap out. I just have to strip the engine all down AGAIN.
Oh well that will teach me to be a clever dick wont it!! Trying ro save a few quid its now cost me DOUBLE to get the van running right.
 

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Cheap Bluetooth OBD2 dongle, could be sub £10, Torque App on an Android phone and see if you are getting real time data for boost, voltage etc. This will be dependant of data (not fault codes) available/coming out of OBD port (a post on years vs data availability which forum members could add experience too would be usefull) but may allow you to watch boost pressure in real time. The dial headed vacuum shows boost when engine loaded, not ticking over as example.
Vehicle Speedometer Gauge Odometer Motor vehicle
 

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Discussion Starter · #16 ·
Hi There


Cheap Bluetooth OBD2 dongle, could be sub £10, Torque App on an Android phone and see if you are getting real time data for boost, voltage etc. This will be dependant of data (not fault codes) available/coming out of OBD port (a post on years vs data availability which forum members could add experience too would be usefull) but may allow you to watch boost pressure in real time. The dial headed vacuum shows boost when engine loaded, not ticking over as example.
View attachment 206848
I did buy an OBD dongle and tried to use this TORQUE app but it doesnt work on iOS. Plus my OBD port is totally dead which is a big problem as I DTC codes would help me.
 
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