Car mechanics - hel...
 

Car mechanics - help please ... VW Golf engine issue

 Aus
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Hi, wife has a a VW Golf 1.4 TSi dsg 2009 (7 speed auto gearbox), 75k miles. 

I took it today for a long journey and noticed if you accelerated hard/floored the accelerator there was a noticeable judder/jolt as it changed gears (after the first time noticing it I did a few experimental accelerates).  This was especially noticeable if cruising at 60mph and then accelerating hard, so 7th gear dropping to e.g. 4th.  Several times after this I got a flashing engine light warning, and then I've now got a peermanent yellow engine light warning.  Otherwise the car was great, cruised very smoothly, mpg good.

Also, there's (possibly) a slight roughness when pulling away gently from standstill and this disappears from 10mph up.

If one accelerates gently-normal it's smooth on all gear changes.  The idle is solid.  There's no random gear changing.

I'm hopeful for a coil pack fault or dirty injectors as it does lots of short journeys, but any suggestions from knowledgeable people?!

Cheers


 
Posted : 08/01/2026 7:44 pm
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First thing would be to get hold of a code reader and see what that says. May be a bit obscure but should give some clue to the source of the issue. 

IIRC yellow lights might reset and clear the OBD memory if you switch off the engine so you might have to try and force it on again. 


 
Posted : 08/01/2026 8:02 pm
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When was the last time the gearbox was serviced? 
Only just got into the VAG world after a few years with BMW but picked up that the autobox (is it a DSG) needs a service every two years.


 
Posted : 08/01/2026 8:28 pm
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Code reader needed. Sounds like what my 1.4tsi did a few days before the injectors stuck open, which caused more damage. So I’d get it checked for codes ASAP. 

Hopefully just coil packs or spark plugs though. 


 
Posted : 08/01/2026 8:37 pm
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Code reader first.

DSG might need an oil change, but pop the bonnet and see if you can rock the engine forward and back - the lower engine/gearbox mount may have deteriorated - cheap part but has rubber bushes that degrade. You may need to jack the car up and check.

Not so sure it would cause an engine fault, but repeated acceleration might cause a sensor to detect something.


 
Posted : 08/01/2026 8:43 pm
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Coil pack is a good possibility - took ages to get my car to throw a code when it developed some rough running, but that wasn't on gear changes. Once the code was up, I could change the coil pack.


 
Posted : 08/01/2026 9:01 pm
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IIRC the 7sp DSG may well be a dry clutch and, if so, doesn't need an oil change.  Although new oil is never a bad thing.


 
Posted : 08/01/2026 9:15 pm
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Posted by: GlennQuagmire

IIRC the 7sp DSG may well be a dry clutch and, if so, doesn't need an oil change. 

Even if the clutch is dry, the gearbox won't be and auto boxes have filters that need replacement occasionally too. I'd still be finding what any codes are first though. 


 
Posted : 09/01/2026 7:48 am
 Aus
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Morning, so headed off to the garage to get a diagnostoic check but when I started the car this morning, no warning light.

So experimenting showed:

- no problems with gentle driving

- flashing engine management light + a judder when accelerating hard (much less so in sport mode)

- and new today and haven't seen before, hard acceleration and the EPC warning light came on, and then very rough running.  Switched off for 2 mins, restarted, no warning lights and fine under gentle driving

Any clues? (and appreciate diagnostic check is good, trying to find a VW specialist to do this)

 

 


 
Posted : 09/01/2026 11:24 am
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Could be coil pack on the way out - the car should have stored some codes. Mine didn't store a code or even engine light. It wasn't until it actually came on could I plug in reader, misfire on No3 cylinder. New pack ordered, car fixed. Without getting it read, you'll never know.


 
Posted : 09/01/2026 11:39 am
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Google says

 

The EPC (Electronic Power Control) light signals a fault in your vehicle's electronic systems, often related to the throttle, cruise control, traction control, or engine management, commonly seen in VW/Audi models. It can indicate issues like a faulty throttle body, bad sensors (brake pedal, crank, ABS), wiring problems, or ignition issues, leading to reduced power, rough idling, or poor acceleration,


 
Posted : 09/01/2026 11:41 am
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I had juddering weirdness with my Yeti 1.4TSi when the throttle body failed, your issue definitely sounds fuel/ignition related


 
Posted : 09/01/2026 11:41 am
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Skip the diagnostic check at the garage - it'll cost the same as a decent VAG-specific code reader, and armed with that you can go in and say 'my mk7 Golf keeps doing this under these conditions. I've scanned it and it comes up with P0xxxx code. I can clear it but it comes back', and go from there. That's assuming it does come back - sometimes clearing them is enough.

Without a fault code it's anyone's guess.


 
Posted : 09/01/2026 11:41 am
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Have a look at Foxwell code readers. I have one that was £150 but it’s Porsche specific and covers both my Cayennes so was worth it for me. A friend has a newer version for his Boxster that is also very good. Cheaper less specialised Foxwells are available

I bought mine from the below link, no affiliation but good service.

https://m.gendan.co.uk/choose.php

 

 


 
Posted : 09/01/2026 11:55 am
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https://www.uobdii.com/wholesale/vident-v301-car-diagnostic-scanner.html?srsltid=AfmBOooXYk-hW4Rwbj1KasLNcS7YhpJleOuTiioQbdb-P3ddJsGAJ7V5

I've got one of these - I think it was 60€, but it's been brilliant. Can reset service indicators and wind back handbrake calipers as well.


 
Posted : 09/01/2026 12:01 pm
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I've had similar symptoms (on a very different VW engine) when the fuel filter was in bad need of changing. Doesn't look like that was a standard service item at the garage I use so no idea how long it had been in the car but swapping it out for a fresh one got things back to normal. 

 

Th other thing that might be worth considering (if you have one) because of the juddering under heavy acceleration is the clutch. Fairly sure I've had a bit of slipping when being enthusiastic with the accelerator just before a clutch master cylinder let go dumping all it's hydraulic fluid onto the plates. 


 
Posted : 09/01/2026 1:03 pm
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EPC often set by a low voltage issue. Give us your location, as I'm sure somebody on here will be close with a scan tool. Pissing in the wind without a scan.


 
Posted : 09/01/2026 1:16 pm
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Posted by: bigginge

Th other thing that might be worth considering (if you have one) because of the juddering under heavy acceleration is the clutch. Fairly sure I've had a bit of slipping when being enthusiastic with the accelerator just before a clutch master cylinder let go dumping all it's hydraulic fluid onto the plates. 

And on a dry clutch 7-speed VAG DSG this is surprisingly likely.

One of the reasons I sold our Leon with the same 1.4tsi ACT with 7sp DSG....Great engine, lovely driving car, nice gearbox, sooo smooth and rapid. £3k bill when the dogily designed 'sealed for life' dry plate gearbox shats itself...


 
Posted : 09/01/2026 2:01 pm
 Aus
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Thanks all.  Had the car booked in for a scan this Weds, but on advice above, will buy a scanner and post up fault codes.

Much appreciate the guidance (and fingers crossed it's relatively minor as it's a lovely car)


 
Posted : 09/01/2026 2:09 pm
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MAF sensor or Fuel filter would be my guess. If its a turbo then MAP sensor.

There are some reasonably priced smart phone code readers now, most will also clear codes but reset service lights


 
Posted : 09/01/2026 6:21 pm
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Has similar with my 1.4tsi 2009 manual. 

new plugs to start and then new coil packs. not expensive from euro car parts.


 
Posted : 09/01/2026 6:53 pm
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We have a 2010 Jetta with the DSG box and it's noticeably jerky in 1st or reverse gear. I had a quick search and apparently it's a pretty common issue, with people suggesting a warped clutch plate? DSG apparently has 2, so should only happen on odd gears. Maybe similar to yours?

I haven't done anything about it as it sounds expensive 😐 


 
Posted : 09/01/2026 7:26 pm
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Slight thread hijack but kind of related.  But my car is playing up now.

Seat Leon 2014 1.8tfsi petrol.

Went to start it this evening and after starting, for maybe 2-3 seconds, there was quite a loud rattling/metallically noise - quite loud as I had the door open when I started it.

I'm thinking maybe the starter motor hasn't disengaged quickly enough?  Although it didn't sound like grinding gears but maybe?

The car is going into the garage for an MOT soon so will mention it to them but any pointers would be useful if anyone has any ideas?


 
Posted : 10/01/2026 9:21 pm
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Went to start it this evening and after starting, for maybe 2-3 seconds, there was quite a loud rattling/metallically noise - quite loud as I had the door open when I started it.

Isn't that a chain driven engine?  

Problem cam chains often rattle when cold.  

Some of the TSI engines had a reputation for chain issues (although mainly a certain generation of the 2.0's iirc).  I might not leave that too long before someone takes a look.  


 
Posted : 10/01/2026 9:28 pm
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Sounds like either a- stretched chain or chain tensioner needing some oil pressure to get it to take up the slack or a hydraulic tappet also in need of oil to work correctly 

If it was metronomic then tappet , random rattle possible chain or tensioner 


 
Posted : 10/01/2026 10:07 pm
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Thanks for the advice, appreciated.

I'd say more random noise so the chain could be culprit.  I'll keep a close eye (or ear) on it, if it persists I'll take it into dealer (car has an extended warranty so hopefully replacement is covered).


 
Posted : 10/01/2026 10:35 pm
 Aus
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Hi, so I've bought a diagnostic tool and it's come back with:

"P0300  07E8  Generic  Random/multiple cylinder misfire detected"

And scrolling thru the other various checks, no other faults were flagged (albeit it's prob a limited range of checks).

So is a good step to replace the 4 plugs and coil packs?

Cheers


 
Posted : 12/01/2026 6:23 pm
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First thing i would do is to remove and visually check each plug for cracks in the ceramic , clean then and gap them.

If this does nothing and its still missing then its parts darts , If they look ancient then new plugs first . If they look Ok new coil packs.

 

 


 
Posted : 12/01/2026 6:42 pm
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No. Clear the code, take it for a run, and see if it comes back.


 
Posted : 12/01/2026 8:14 pm
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Posted by: misteralz

No. Clear the code, take it for a run, and see if it comes back.

And if the light does come back on again, don't turn off the engine before you plug the reader in and do a new scan. 


 
Posted : 12/01/2026 8:27 pm
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Nah, if it's thrown a code then it doesn't matter.

FWIW, P03xx codes are misfires. 300 is generic, 301 is cylinder 1, 302 is cylinder 2, and so on.


 
Posted : 12/01/2026 8:50 pm
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when were the plugs and coil packs last replaced? 

id be spending a few quid for piece of mind


 
Posted : 13/01/2026 9:40 am
 Aus
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Hi, thanks again.

So I cleared the fault code, took it for a spin, misfire under load.  Ran diagnostic check and gave me:

P0301 Cylinder 1 misfire detected.

Hoping this is good news as narrows down the parts options? So am I sensible to focus on cylinder 1 - check spark plug (cracks and gap) and replace, try the car.  If misfire continues, replace coil 1.

Good plan?


 
Posted : 13/01/2026 10:11 am
 kilo
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can you swap the coil to another cylinder and see if the fault follows the coil? (IANAMechanic!)


 
Posted : 13/01/2026 12:11 pm
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can you swap the coil to another cylinder and see if the fault follows the coil? (IANAMechanic!)

Is the correct answer ✅


 
Posted : 13/01/2026 12:33 pm
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Yep, swap the coil packs from 1 to 2, see if the problem moves. If it does, it's the coil pack. If it doesn't, it's the spark plug OR the loom to coil pack 1.


 
Posted : 13/01/2026 1:00 pm
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 Aus
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Excellent, will do and report back


 
Posted : 13/01/2026 1:30 pm
 Aus
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Ok, so I've switched the coil pack 1 with coil pack 3.
Same symptoms and error of cylinder 1 misfire.
So presumably coil pack ok.
Time to replace spark plug, and should I replace all 4 or just no.1?


 
Posted : 14/01/2026 1:29 pm
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All plugs, not just one !

 


 
Posted : 14/01/2026 1:50 pm
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If you still get a misfire, there could be a wiring loom fault or something more serious in the ignition.  Once you change the plugs, do the coil swap again, but maybe a different cylinder, just to be sure.  The thing is, once a coil pack starts to go, it usually means the others are getting long in the tooth.

I replaced one pack, then a year later, another went. 


 
Posted : 14/01/2026 1:53 pm
 Aus
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Will do and thanks.
And genuinely out of interest, why all 4 if assume just 1 cylinder misfiring?


 
Posted : 14/01/2026 1:55 pm
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Yeah, do all the plugs and coil packs. Why not just one? Because this one coil pack's starting to go and they have a finite life. You could replace one, but you'll just expose the next weak link. Toss the known bad one, and keep one of the old ones  in the car as a 'poor spare'. That way you're guaranteed to never need it. 

I'd also inspect the state of the multiplugs to the coil packs when you replace them. Quite often they get gorillad off which can lead to poor connections.


 
Posted : 14/01/2026 2:03 pm
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Plugs are cheap(ish) so replace all 4 and eliminate that. Coil packs can be expensive, although looks like they are about £40 each for a 1.4 TSI. Worth getting one with a mind to change all of them ?


 
Posted : 14/01/2026 9:28 pm
 Aus
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Hi, thanks for all the guidance.  

I replaced all 4 plugs yesterday (couldn't get the coils locally so thought I'd try just plugs), 15min spin and all seems good.  Obvs need a bit more testing but fingers crossed.  Will update in a few days...

 


 
Posted : 15/01/2026 12:23 pm
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This thread's prompted me to get fresh plugs and coil packs for my Golf. I think I've changed the plugs in the last 60k, but I can't say for sure. The (actually cheaper) Audi R8 coil packs are at least 100k old now.


 
Posted : 15/01/2026 12:29 pm
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Sort of related. When I had an Octavia (so a VW engine in disguise) 1.8 tsi, I had to change a coil pack when ai had a mis-fire (doing as other said of swapping coil packs and seeing if the mis-fire changed cylinders - which it did. Swapped out for a new one, all good.

Then had a 2nd one fail within about a week. Different cylinder.

So just to say that if the fault re-appears not too long afterwards- don't assume you didnt fix the problem - it is quite possible that a 2nd one happened.  


 
Posted : 18/01/2026 1:24 am
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Posted by: Aus

Hi, thanks for all the guidance.  

I replaced all 4 plugs yesterday (couldn't get the coils locally so thought I'd try just plugs), 15min spin and all seems good.  Obvs need a bit more testing but fingers crossed.  Will update in a few days...

 

What was the condition of the plugs?

 


 
Posted : 18/01/2026 8:48 am
 Aus
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Hi all, 

Car running well so far after changing all the plugs.  Plugs had no obvious cracks, the gap on each was close or accurate (0.7mm), the pin of the plug where it sparks slightly corroded/grey, the plug itself a little sooty ... 


 
Posted : 18/01/2026 10:16 am
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Posted by: Aus

Hi all, 

Car running well so far after changing all the plugs.  Plugs had no obvious cracks, the gap on each was close or accurate (0.7mm), the pin of the plug where it sparks slightly corroded/grey, the plug itself a little sooty ... 

Good stuff. Were any of the plugs dirtier/cleaner than the others?

 


 
Posted : 18/01/2026 11:14 am
 Aus
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The threaded section on each plug consistent. But 2 plugs (cylinder 1 &3) had 'soot' on the white body of the plug


 
Posted : 18/01/2026 6:52 pm
 Aus
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All running v well so fingers crossed.  Thanks for the advice


 
Posted : 23/01/2026 9:59 am
anorak reacted
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Thing with plugs these days is they last a hell of a long time with the modern electronics. Dare I say it, we've not replaced the plugs in MrsF's Qashqai (1.6 VVT) in 10 years. Why, it's an absolute pig of a job that needs loads of stuff removing, including the throttle body, and then that needs re-setting (either a ODB reader or a magic accelerator and button press sequence). When they do fail you know about it, same with coil packs.

Glad it's been a simple fix.

 


 
Posted : 23/01/2026 2:07 pm