Help needed.

[Reyne111]

Originally Posted by S60D5-185

+1 Boost leak seems highly likely.

Check the orange seals on both ends of the resonator box which leads off the Turbo. Very common issue.

Going in the Garage on Tuesday to go onto the smoke machine. Hopefully will get to the bottom of it.

[Reyne111]

Originally Posted by SwissXC90

That doesn't rule out a boost leak. Check it with a smoke machine.

Back from the Garage, no boost leak.

Driving it home from the garage going up a hill the car suddenly got full power back and about 3 minutes later lost it again.

I am banging my head on my desk as we speak.

[SwissXC90]

Time to do some live data logging in VIDA

[Reyne111]

Originally Posted by SwissXC90

Time to do some live data logging in VIDA

They did that as well.

The car has been re-mapped due to a DPF delete, they thought that the mapping was bad as the car was only asking for small amounts of a boost once being driven and data being logged, (maxium 1.6bar at full throttle) however, the full power spell today would blow the ECU theory out the water no? When I say it had full power for a few minutes, I mean, it flew!

[XC90Mk1]

Originally Posted by Reyne111

They did that as well.

The car has been re-mapped due to a DPF delete, they thought that the mapping was bad as the car was only asking for small amounts of a boost once being driven and data being logged, (maxium 1.6bar at full throttle) however, the full power spell today would blow the ECU theory out the water no? When I say it had full power for a few minutes, I mean, it flew!

I would be tempted to stick it back to normal map (Volvo) and add the DPF back in. I am not going all ‘environmental’ or anything it’s simply the observation that mine is now on over 120,000 with original DPF and no issues.

Incidentally….. and perhaps adding 2 and 2 to make 6 my seals on the resonater (as s80-185) mentioned above went and it logged a fault code with the DPF (common). The seals were fixed and the DPF has been fine over last 10k plus.

I wonder if the seals are leaking and the previous owner junked the DPF thinking that was at fault.

The 185s are punchy units and I am not sure I would remove a map from Volvo and replace (each to their own however).

[Familyman 90]

The issue is people suffer a DPF problem, can't afford to diagnose and repair the car properly, and thus do the delete and remap without first fixing the fault that had caused the symptoms in the first place.

As aforementioned, the DPFs on these are very robust systems and simply do not cause problems on their own. Its inevitably a fault elswhere that causes the DPF to act up, and if some previous owner has done a DPF delete I would think likely there is still a problem somewhere to be identified.

Boost leaks are indeed very likely to do this and cause revving and/or power problems, and cause the DPF to soot up as it runs rich.

[Reyne111]

Originally Posted by Familyman 90

The issue is people suffer a DPF problem, can't afford to diagnose and repair the car properly, and thus do the delete and remap without first fixing the fault that had caused the symptoms in the first place.

As aforementioned, the DPFs on these are very robust systems and simply do not cause problems on their own. Its inevitably a fault elswhere that causes the DPF to act up, and if some previous owner has done a DPF delete I would think likely there is still a problem somewhere to be identified.

Boost leaks are indeed very likely to do this and cause revving and/or power problems, and cause the DPF to soot up as it runs rich.

Smoke machine has been put on and no boost leaks were found.

Im in between two diagnostic solutions, I have a very caple mapping guy who can go in and check the map to see if anything is wrong.

Or, remove the DPF and physically look inside to see what is happening in there. I dont think it is a coincidence that since owning the car (2 months) its had no power, the first time someone has taken part of the exhaust system off ( back box) to check for a blockage, the car decides it has full power again for 3 minutes.

I live on the isle of wight, we have no duel carriageways or motorways so if i can avoid having a DPF its better in the long run. All the garages here are full of cars have static regens

[arcascomp]

Digging back through my grey matter here, so someone else please correct me if I'm suggesting nonsense!

I seem to recall that the rubber pipe from Turbo that goes down to connect up with the air pipe that runs under the engine can soften with age. The pipe itself will look fine and doesn't leak any smoke so all seems fine, but because it's aged it becomes floppy and collapses on itself causing airway congestion under harder driving conditions.

You should be able to feel down and try to squash the pipe, I recall a good one should feel pretty firm and resistant to squashing, but a worn one will be easy to squash.

As I said at the beginning, I may be talking utter rubbish here!

[ltec]

Your mapping guy is the man to go to. If he's any good he will be able to tell exactly whats happening or not happening. Removal of the dpf will leave you more power and better mpg.
Just spoken to someone last week that removed a dpf from a volvo, not a xc90. He's had it from new and its pretty old now. He says she drives better than she ever did, even when new and big improvement on mpg. Wished he done it years ago.

[Reyne111]

So here is another spanner to throw into the works....

I just suddenly thought about the MAF. So I unplugged it and did a quick test drive, no difference and no warning light.

This is a bad MAF if I am correct right?