Almost total loss of power during regen?

My Passat seemed to lose almost all its power today driving home which coincided with a DPF regen. Couldn’t get above 2,000rpm and could barely get up hills, had to drive on 60 roads topping out at 20 with the hazards on.

No warning lights, no stored codes and turbo boost showing what it should.

At the time it was about 26C outside, I had the air con on max, bikes on the roof and a few passengers and was driving up a few steep hills so perhaps it just got too hot but I feel like that shouldn’t happen and the temp gauge didn’t go above the normal 90C position.

I pulled over after a bit and let it finish it’s regen after which it seemed back to normal straight away.

It’s booked in for a heater core exchange next week so I’ll mention it but wondering if anyone has had similar and what it was.

2.0tdi 2015 Passat estate, 126,000 miles.

Anyone?

No, the ex’s passat (b6?) was faultless my 159 would clog the dpf constantly and need a forced regen every month.

What you describe sounds exactly like when an injector went on my transit connect a few weeks ago, but that also threw up awarning light.

which coincided with a DPF regen

I don’t own a Passat, so maybe they do something that other cars don’t, but one of my bugbears about DPF regens is the the car doesnt generally tell you that its doing one. So whats telling you the car is in regen rather than anything else?

Not having a warning light means theres not really anything for anyone to suggest (could mean your Engine Management light has stopped working maybe – do it light up when you turn the ignition on?). If it is DPF related then the cause can be the DPF itself – they don’t last for ever – the particulates that the filter catches are a mostly soot and little ash. Soot is combustible and is burnt away when the DPF regenerates. Ash isn’t combustible so will accumulate over time until the filter is full and needs replacing. 126k could easliy be the useful lifespan of a DPF. Using the wrong grade of oil at at anytime in the life of the vehicle can cause premature ash build up. Issues experienced during a regen itself could be the extra fuel introduced during a regen clogging what little filter capacity is left

But a DPF related issue could actually be anything upstream of the filter – injector problems, turbo problems and so on

telling you the car is in regen rather than anything else?

I would regard myself as mechanically hyper sensitive – I tend to notice every little change in noises, rattles etc so I might notice more than average but on my 2012 (same gen as OP ) Passat.

– exhaust note gets boomy / sounds like it’s blowing

– the dsg hangs onto gears like a teenager with a dustbin exhaust

– it develops a clackety idle

– fan noise

– sluggishness (but not as much as the OP)

– start stop deactivates

– range drops sharply 5+ miles of range loss to 1 mile driven

Our SMax (a manual) mostly had the same symptoms and it used to really boom from the exhaust and stutter at idle as well.

Back to the OP what you’re describing sounds to me like it could be a split or loose intercooler hose.  Get your friendly local garage to check them.  When I had one go on my old Mondeo it had many of those symptoms and was loads worse under load as the forces on the engine opened the split further.

Sounds like when my Touran died, whole exhaust system had clogged up, started with being a bigger tk start some mornings then odd loss of power moments. Eventually packed up completely on a hill. We did have an engine management light come on and a MAF sensor error on the diagnostics.

– exhaust note gets boomy / sounds like it’s blowing

– the dsg hangs onto gears like a teenager with a dustbin exhaust

– it develops a clackety idle

– fan noise

– sluggishness (but not as much as the OP)

– start stop deactivates

– range drops sharply 5+ miles of range loss to 1 mile driven

So a bunch of symptoms that seem like could seem like a fault that the driver has is to extrapolate as the car doing something it’s supposed to. Would be so much more helpful if there was a light on the dash to tell you the car was doing that for a reason. If I turn my lights on theres a light on the dash to tell me the lights are on. If I put fuel in the dash informs me theres fuel. I’ve never understood why regens aren’t signalled.

I knew it was doing a regen because of the reasons garage dweller has mentioned above, it’s really obvious when you know what to look for, but I also have an app that connects to my code reader and shows you the regen in progress so I could see it. Almost as soon as it completed the regen cycle the car went back to working normally.

I’ll get the garage to check for any split or loose hoses in case.