SinisterKid97

Not sure the remap type - just done by a remap/diagnostics guy at a nearby garage. I could drop him an email to ask? I always run the car on Tesco/Shell 99. Very occasionally 97, if 99 is unavailable, but never 95. Usually Tesco because it's cheaper, but Shell V-Power every couple of months or so. The warm restart 2-3 second chugging/struggling sound first occurred back in May, on the first very warm day of the year. The remap was done about 8 months prior to that.

Car back from the garage. The startup chugging was nothing to do with the diverter valve, and is still present after the GFB DV+ has been swapped for a 'Rev G'. So... I'll likely live with the startup chugging and rattling until its next MOT, and get the timing chain/tensioner replaced, if there's nothing else major that needs doing. The 'Rev G' seems a bit smoother than the GFB DV+. I haven't yet driven it enough to say whether I prefer it on not - "subtly different", rather than "better/worse". The performance is still there, but it feels smoother in its power delivery now, rather than the torque/boost all arriving in one big lovely lump. And as for the lift-off/overrun jerkiness... the engine mount and upper+lower gearbox mount needed to be replaced. They said that the engine mount was 75% worn, and the others were showing signs of aging. I'd already had the lower dogbone mount/bush replaced earlier this year, so that's now all of the mounts done. Jerkiness gone and the lift-off and gear changes feel sharp again.

Is your car chugging during normal driving/operation? Mine only does it for 2-3 seconds, when it's restarted after already being warmed up. Normal driving is fine, idle is smooth, and performance is generally strong. With regards to parts... I haven't bought many myself, but have used Autodoc and AwesomeGTI in the past. Both recommended. Autodoc is often cheaper that garages quote for parts, but takes 2-3 weeks for delivery to the UK.

The car is finally back in the garage to have the GFB DV+ replaced with a 'Rev G'. Fingers (and toes!) crossed that this is the offending item and the car drives more smoothly again afterwards. I've asked them to also check the engine/gearbox mounts for any sign that those need replacing too (lower dogbone mount/bush was replaced earlier this year, so that should be fine, but the other two are possibly still original). Just looking for anything that could cause the off-throttle/lift-off jerkiness. I'm fairly convinced that both the warm restart chugging/stumble and the metallic rattle on cold start (it either does one or the other, sometimes neither but never both together) is the timing chain and tensioner. I'm not expecting the diverter valve replacement to change either of those, but hopefully it makes some positive difference. We shall see!

Yeah, sounds like you'd make good use of it - that's quite a collection. I'd like to be able to do things myself, but bulbs, wiper blades and cabin filters are about my limit! Maybe replacing the odd bit of trim, and I've replaced a few switches myself - centre console central locking button and the on/off toggle for the cruise control. Both were intermittent for years until I wondered if I could fix it myself, rather than just putting up with it. Turns out, I could. I probably could do more, but I've got a healthy awareness of my lack of ability and experience - I'm capable of following instructions accurately and carefully, but it's the whole "what to do when something goes wrong" bit that scares me. I can't afford a new one, can just about afford to keep this one running... I don't want to start tinkering with engine stuff myself, in case I break something, or damage it in a way that's hard/expensive to put right. Changing the diverter valve looks easy enough, but I'm probably best to get the garage to do it.

I've owned this car for 14 years and have a growing appreciation for it. Loved it for the first 3-4 years, then for a while it just became another tool to be used - partly for financial reasons, I just kept it going with the bare minimum (cheap tyres, interim services instead of full, etc). But then 2-3 years ago (as electric and hybrid cars were becoming more common), I looked into getting a new car and realised just how expensive that would be! Thought I'd rather try to keep this one going for as long as possible, even though my wife doesn't quite see eye-to-eye with me on that one - haha! "I hate that car - I don't understand why you don't just get a new one??" ...like I've got £30k tucked down the back of the sofa...?! So... I started looking into the key wear-and-tear and long-term "engine killer" items for it, and have been trying to remedy as many of them as financially possible over the last 12-18 months. I'm under no delusions that I can make the car last forever, but it feels like it's got a fair bit of life left in it, as long as I start proactively looking after it with some preventative maintenance... rather than just living MOT-to-MOT and only fixing what I'm told to. Trying to find the balance is a bit tough, though - not being a mechanic, knowing where to draw the line between what's worth fixing/replacing, and what is just throwing money away.

When idling, it was fluctuating between 690-720... so yes, hopefully that means that the fuel side of things is all OK for now. Thanks again for your help and quick replies - very much appreciated. I'll post an update when I've had the DV replaced.

Checked it again a little while ago - no pressure spikes. Turned it on, idled at around 700 psi, turned it off. Let it climb to 1000, then turned it on again - immediately dropped to 700. Turned it off, let it climb back up to 1200, then turned it on - dropped back to 700 again. I'll see if my local garage can replace the diverter valve with a 'Rev G' and see what happens.

Ah OK, thank you. I'll give that a try. So... do the same as I did before, but wait 5-6 minutes for the pressure to build up to 1200, start the engine, and see whether the pressure spikes or drops. When I first plugged the OBD in earlier today and turned the ignition on (just to position 2, not actually starting the engine), I noticed that the pressure was around the 1500 mark, then dropped to around 700 when I started the engine. I wasn't properly looking or checking at that point, though, so I'll try it again and see what happens with a proper test.

Back in July/August, I did some OBD tests to monitor coolant temperature too, and those came back fine. The coolant temperature readings matched what I was seeing on the dashboard gauge, and the rise in temperature was normal/linear and consistent with the driving type. Warmed up fine during slower town driving, then started to drop when driving at faster speeds and therefore more airflow. The over-cooling also seemed slightly stronger when the aircon was on - second fan causing even more airflow in the engine bay, perhaps?

I just went for a little drive to get the car up to temperature, then restarted it after 30 seconds or so to check that it still made the chugging/stumbling sound. It did, so I restarted the car, monitoring the fuel rail pressure with the OBD gadget. It idled at around 700 psi, then after I switched the engine off, the pressure gradually began to climb to 1200 over the next 5 mins or so. Google Gemini tells me that is the sign of a healthy and sealed HPFP and PRV, and that it would've likely climbed a bit more if I had monitored it longer. Also says that a leaking injector would've also caused the pressure to drop, rather than climb... suggesting that they're likely fine too. Does that sound accurate? Given these results, Gemini suggests that the prime candidate for the chugging sound is the GFB DV+, sticking/binding when the engine is warm. I'll see if I can get it swapped for a 'Rev G' and check if there's any difference.

OK, thanks again for your help. Yes, the chugging/stumbling startup noise happened before the injector replacement. First noticed it towards the end of May (first day of really warm weather), then the injectors were replaced at the end of June, along with the carbon clean/walnut blasting. The DV+ was fitted around mid-September last year, shortly after the stage 1 remap. So... it'd been installed for around 8-9 months before the problems started. Given the unusually warm summer we've had, maybe that timescale fits with the time it likely needs a bit more oil? Or maybe they are generally supposed to last a lot longer before needing any additional maintenance. No idea.

I've got an OBD gadget (the Veepeak OBDCheck BLE+), so I'll see if I can monitor a drop in fuel pressure using that. My local garage have been paid twice for diagnostics on the stumbling/chugging noise and neither time have found anything, so I'd rather run a few tests myself at this point. I'm not confident enough to remove the diverter valve myself (I've read that it's under the car, accessible via the driver's wheel arch?), so I'll see if the fuel pressure readings will point me one way or the other. If it maintains pressure, then that largely rules out the HPFP and PRV, and the GFB DV+ is likely to blame - correct? Swap that out for a 'Rev G' and the problem should go away? If it drops, then likely get the PRV replaced first (as it's cheaper), before moving on to the HPFP. Does that sound like a reasonable plan?

Thanks for your help. If it was the HPFP, would that show any other symptoms? i.e. loss of power when driving, misfires/stutters during heavy acceleration, etc. I haven't noticed anything like that. I don't know if it would show any warning lights or error codes along those lines, but haven't seen any of those either. If it's just the pressure dropping off (rather than any of the other symptoms), I saw another suggestion online that it could be the fuel PRV with a slight leak/bleed - does that sound plausible? When the weather is cold, there is sometimes a 1-2 second metallic rattle on cold startup and maybe 2-3 times out of 10 it will crank longer than usual before starting. I'm assuming that's the timing chain/tensioner that might need looking at, but it's not been enough of a problem to warrant further investigation so far - it's hardly done it at all during the summer. And thanks also for the info on the GFB DV+. I too have read a bit about the piston sticking if it's not properly lubricated. I supplied the part to the garage when it was fitted in September last year, and mentioned the need for oiling the brass piston, so I assume that was done. When I questioned about the need for oiling it routinely, the mechanic dismissed the idea, saying that it was supposed to be a "fit and forget" part, and he'd be surprised if it needed anything at all in the next five years. That doesn't fit with what I read online! Feedback suggests that it's a good part whilst working well, but it does need oiling every now and again. I'm very tempted to have the VAG/Pierburg 'Rev G' diverter valve fitted, but I don't want to throw more money at it if the GFB is actually fine and isn't the problem. I suspect that it might be the solution with the slight lift-off/overrun jerkiness that I'm experiencing, as some of the symptoms and timing of the fitting/issues seem to fit.

I'm trying to troubleshoot a niggle with my 2006 Octavia VRS, that only happens when starting the car after it's already warm. I'll try get a decent video/audio of the symptoms as soon as I can, but wondered/hoped if anyone would recognise the problem from a brief description. Octavia VRS 2.0 TFSI / MK2 2006 / EA113 / BWA / Manual / 123k miles / Stage 1 remap. 2-3 second stumble/chugging sound when engine is started whilst already being warm/recently used. Sounds like the engine is either getting too much or not enough of something, before sorting itself out and settling. Normal cold starts are generally fine. Normal running/driving is fine and still pulls strongly. Symptoms first occurred in May 2026 - the first day of the really hot weather (I'd spent around four hours throughout the day driving mostly short journeys, some fairly "spirited" driving). No relevant error codes. Work already done in the last 12 months (some required, some preventative maintenance): cam belt and water pump, four new injectors, cam follower, PCV, intake carbon clean, spark plugs, coil packs, stage 1 remap and diverter valve (GFB DV+), new battery, EVAP valve checked and clear, vacuum system passed a smoke test. Other minor niggles: throttle lift-off/overrun feels a little rough/jerky sometimes; temp gauge sometimes drops to 70-80 on motorway journeys. My local garage have had the car in twice for diagnostics and couldn't identify the problem. Had it earlier this week, after I asked them to check for the thermostat sticking/failing, to double-check the EVAP valve, and to check that the GFB DV+ diverter valve wasn't sticking (all suggestions from forum research, and ChatGPT/Gemini), but the garage couldn't find anything obviously wrong. I was very tempted to get them to replace the thermostat and EVAP/N80 valve anyway, since they're fairly inexpensive (parts and labour), but they advised that unless I want a full engine rebuild, it's probably best to stop chasing little niggles if the car generally runs fine. A separate VW/Skoda/Audi specialist also had the car for a week (a couple of months ago, to replace the fuel injectors and perform a carbon clean/walnut blast) and couldn't replicate the chugging sound either. Presumably because they didn't restart the car after it was already warm. They also mentioned that the intake manifold motor/actuator was sticking a bit, so they took it out, cleaned it up, lubricated, etc and put it back in (doing whatever reset/coding was necessary too), and said to keep an eye on any related error codes popping back up. So far, nothing. Does this startup chugging sound familiar to anyone? I'm trying to not just throw parts at it and hope for the best, as I've spent enough already. I'd just like to get these last few niggles sorted out, then I can relax a bit - until the next time, haha! Thanks in advance. I'm very much not a mechanic - just stuff I've read online. Any help is greatly appreciated.