Lumpy idle [Resolved]

[coupcoup]

My van has developed a lumpy noisy idle. Sounds almost like it’s missing a beat. Come out of nowhere. Drive 200 miles at the weekend no problem. Filled up at shell. Ad blue is topped up. No reason for a problem. It’s done 41,000 miles and is a 2018 150 4motion


Any help would be much appreciated as I’m about to tow a caravan with it in a couple weeks for 400 miles.

 

[DaveD]

My van has developed a lumpy noisy idle. Sounds almost like it’s missing a beat. Come out of nowhere. Drive 200 miles at the weekend no problem. Filled up at shell. Ad blue is topped up. No reason for a problem. It’s done 41,000 miles and is a 2018 150 4motion


Any help would be much appreciated as I’m about to tow a caravan with it in a couple weeks for 400 miles.

Do you have any lights on the dashboard, like EML, when it runs lumpy?
Does it have normal power when under load?

 

[Howzat]

Your 1st point of call has to be scanning for fault codes via the OBD. DIY with carista, obd11 or vcds or scanned at a workshop.

 

[coupcoup]

No lights on dash and it does clear up after it’s driven. It’s a bit lumpy to start.

 

[Loz]

Is the idle slightly raised? It could be trying to complete a regeration.

 

[coupcoup]

Idle not raised I don’t think. I took it for a drive and after a mile it felt normal with full power. Stopped it started it again and all was good. But when it’s cold it’s really lumpy. Could it be just rubbish diesel?

 

[coupcoup]

Another thread suggested they’d had a similar problem and it was a cam belt issue the timing had slipped. I know this is a couple months overdue a timing belt but that would be a coincidence wouldn’t it?

 

[Elparkerio]

Had similar a couple of months ago - one garage diagnosed faulty EGR valve, another diagnosed faulty injector. Ended up replacing two injectors (ouch) and it's been fine since. Fingers crossed it's not that! (2016 Shuttle 84)

 

[coupcoup]

So started it yesterday evening and it was all Over the shop. Coughing and farting like no tomorrow. I contacted Brads garage in Aberfeldy. Callum, the trained VW tech there told me to buy a specific bottle of injector cleaner. A vw make. He supplied it actually and I put it in thinking there was no way it would do anything but unbelievably after a couple miles the diesel knock had gone and it was running smooth as. So highly recommend both the product and brads garage in aberfeldy.

 

[Leeabr101]

I had a similar issue recently. No errors kn vcds, no lights on dash. Never been a believer in v power etc however i filled up on this (that hurt the wallet) and added a diesel additive and after 4-5 days I've not had a lumpy start since so very happy!