Tickover speed increasing

[Trev the farmer]

Since yesterday I have noticed the tickover speed has increased. When the engine is warm it revs faster. I noticed today a sulphur smell, so I took the car for a decent run keeping the revs around 2500-3000. When I got home the tickover speed was really revving. Any ideas ???

[amer6R]

Dpf regeneration

[Trev the farmer]

Does the engine speed increase during regeneration ? What do I do to fix it ? Thanks for your help, much appreciated!!!

[amer6R]

Diesel right?
When the car is at operating temperature and the revs at idle are 1000 rpm, take it on a motorway or open road drive speed 60 km/h and revs 2200<2800 rpms and drive about 30 minutes and your idle.revs will go back to 800.

[Trev the farmer]

Ok thanks, I have just been on the M54 following your instructions. When I pulled of the motorway after 35 mins I stopped at the roundabout and the tickover was at 1800, I touched the accelerator with with my toe (lifting the pedal) and the revs went down to 800. I got home and checked the accelerator pedal, it moves freely doesn’t stick but every time you touch the accelerator you have to apply pressure upwards to slow the revs. Inside the car smells of diesel.

[Trev the farmer]

Could it be something like this ?

CD135365-DD88-4DF0-93E0-F27E7E3D6EB9.png (403.06 KiB) Viewed 1006 times

[amer6R]

I would inspect via diagnostics throttle position sensor while car not running 0%, and 100% fully pressed.
If you have it reading more than that then it has an issue. -Diagnostics
Surely it can be checked via multimeter but im not sure how to do it.

Diesel smell can happen as many say dpf rengen, and egr clogg.

[Trev the farmer]

I have taken the car back to the dealer, I have only had it a week so they can sort it out. Nevertheless, I appreciate your help, it’s good to know all this knowledge is available when needed. Thanks again !!!

[Trev the farmer]

I have just been informed my car is ready for collection. They couldn’t find any fault codes etc. They said the car was part way through a regeneration process which has since been completed. I will be interested to see how it drives now.

[amer6R]

Hope it is

[Trev the farmer]

Well, I got the car back. The problem was still there, ticking over at 1800rpm then if you blip the throttle it drops to 800. I ordered a new accelerator pedal from ebay. I then went on youtube and looked at loads of videos regarding vw accelerator problems. I found one video, albeit for a 2.0 TDI, the video said to get in the car, push the accelerator to maximum with your foot, then keeping your foot on the pedal turn on the ignition (don't start the engine) keep the ignition on for a minimum of 10 seconds, then release the pedal and turn off the ignition. I tried this and then drove 6 miles to fill up with petrol, the problem has not occurred since. its early days but its hopeful.

[Trev the farmer]

I went to work in the car today, tickover fine. I noticed that when you brake hard the revs increase slightly, when you take your foot off the brake the revs go back to normal. Weird !!!

[amer6R]

Ah its like anti stall control, this will also hapen when clutching. Pretty annoying

[Trev the farmer]

Yes you are right, it does the same thing when you use the clutch. Is this normal ?

[amer6R]

Yes it is