Hi. I purchased a 2011 Octavia 1.6 tdi estate this year and I've noticed that when going around a corner and then down a steep slope, the car slows & starts kicking back. 

If I take it out of gear & coast down it doesn't do it, so I feel that it's engine related. 

 

I'm due to change the coolant temperature sensor, as I've had issues with the revs going up & the fan coming on from cold, so I'm not sure if this is related to the above. But the above happens when the engine is at normal temperature.

 

If anyone has experienced the above I would appreciate some feedback on what you might feel that it could be.

 

Many thanks

mine does exactly this never got to the bottom of it but it seems to be designed in and doesn't appear to be a signal of any problem.

 

if your revs are up and the fans are on it's probably trying to do a DPF regen - when a cts fails it tends to just drop off

 

what sort of journeys are you doing?

Hi. Thanks for the reply

 

It seems to have improved since the CTS was changed, but I'll see how that goes.

 

My main issue is that the fan seems to come on when the revs go up. Which is most noticeable after a cold start after 5 minutes or so, and this can stay on even after a 14/15 mile journey. Which causes a vibration through the steering wheel. Most noticeable when stationary. Which seems to be caused by the balance of the cooling fan! 

 

I haven't had the car that long, so lately it's just driving on A roads etc. On a daily basis.

@Tezza2020 It's a VAG thing, plenty of threads about this issue. Here's one linked with vw and audi forums, it's normal.

https://www.pistonheads.com/gassing/topic.asp?h=0&f=86&t=1424280

Ok, thanks Kris82. I'm pleased to hear that it seems less like something to worry about now!

 

Have you come across any other owners having the issue that I've described in my other post about the cooling fan coming on from cold.

At the moment the car seems to run a bit rough for a few minutes after a cold start, and then after driving it for a little while the fan comes on.

It drives better when it's warm, but the fan can sometimes stay on for a while.

 

There is only one fan on the radiator

 

You say the coolant temp sensor has been changed so rule that out. 
Obviously as the temp rises in the engine you would expect the water temp gauge on your dash to rise!? Does it?
 

As simple as this sounds, the two prongs inside the coolant tank can build up with grime, thinking the coolant is empty therefore setting off the radiator fans.

 

So to start ruling out problems starting with the simplest first I would clean the two prongs in the coolant tank by scraping off the grime with a flat head screwdriver reaching in.

(Done this myself because I had low coolant light coming on even though it was full).

 

Also could be thermostat not opening (but would show light on dash).

 

Mine after 188,000 miles always a bit rough from cold lol so can’t answer that one.

 

Could be stuck on a regeneration which on our older cars will keep trying to regenerate regardless of cold starts and attempts.

 

Personally if my car, clean prongs in coolant tank first (easy job).  
Drive for at least 30 mins or more if you can quite harsh (with over 1/4 tank) or even more if you can to trigger a regen (even though it’s probably trying to do one).
 

If it was me, check coolant,  check oil, fill up over half , take car for a blast for an hour, to rule out blocked dpf.

 

 

Hi Kris

 

Many thanks for your feedback again.

 

I've checked the prongs in the coolant tank, which were totally clean.

 

There is one thing that I have noticed today, which is that the single large cooling fan doesn't come on when the air con is switched on. I tried this at idle for around 5 minutes and the fan only came on when the engine started to get hot.

 

So I'm just wondering if it has something to do with this!

You should get the car scanned for fault codes, this should make diagnosis easier.

 

If you don't have access to an OBD diagnostics code reader, VCDS etc. then take a look at Carista.

On 02/04/2020 at 17:51, Tezza2020 said:

Hi. I purchased a 2011 Octavia 1.6 tdi estate this year and I've noticed that when going around a corner and then down a steep slope, the car slows & starts kicking back. 

If I take it out of gear & coast down it doesn't do it, so I feel that it's engine related. 

 

 

My view is different to other posts. Does your car have auto stop/start - ie. greenline model?

If so then your car is working normally. On these eco versions, when slowing down by lifting off the accelerator, the alternator is used for energy recovery back to the battery. The effect is like you have gently pressed the brakes. Happens on cornering too but does not happen if you coast out of gear as then the engine is not connected to the wheels.