Hi. Could anyone help with this problem. Bare with me. As previously mentioned my car goes into limp mode when going up a steep hill and going over 2000 rpm approx. I have had answers as to what this could possibly be with the Turbo etc. but now over the last few months the car struggles to start when it's hot and has been driven for a while and I leave the car for maybe 5-10 mins when i try to fire up again ,it may take maybe 2-5 times it feels as though the timing is miles out and it feels and sounds as though the engine is about to exit the car!! Massive vibration too.when it does fire up the revs are higher but drives fine. It Doesn't seem to have the same problem when the engine is cold. I have had a fuel filter just changed and cam sensor and the car drives beautifully when not suffering from these two problems. Hope someone can help

Thanks

Might be starter motor or wiring/battery. It may not be turning engine fast enough when hot. Another fault which I have read about is the coolant temp sensor. Sometimes if you unplug it when hot the car will start.

Have you had it scanned with vcds for any stored fault codes. If its going into limp mode there should be some stored somewhere.

Alasdair

Edited 16 August, 202516 Aug by Alasdair1

Hi thanks for replying with some possible areas to look at. I did have it scanned but it didn't show any issues which is strange so I'm hoping it's not a major issue like fuel pump, injector's etc.

Thanks

Its a long shot but could it be drawing air into fuel line when hot or perhaps the fuel tank vent/cap is blocked? Had an old van that did the same. Fuel cap vent was blocked and caused a vaccum in fuel system. It was enough to eventually colapse tank enough to block fuel pick up. Used to start when cold no bother but wouldn't start when hot. Fine when it cooled down a bit.

Alasdair

21 hours ago, Alasdair1 said:

Might be starter motor or wiring/battery. It may not be turning engine fast enough when hot. Another fault which I have read about is the coolant temp sensor. Sometimes if you unplug it when hot the car will start.

Have you had it scanned with vcds for any stored fault codes. If its going into limp mode there should be some stored somewhere.

Alasdair

Hi. Yes I'm thinking it may be possible it's drawing air in somewhere and I might get it plugged in again just to see if it shows up a fault code. I'll check the possible blockage of the fuel cap vent. Thanks again

When it does it again remove fuel cap to see if theres a vaccum and try starting without cap on. When my van did it due to the wrong cap being fitted it was worse with a full tank

Alasdair

Great . I will give that a try . Thanks

I had this problem when I first bought my 1.9PD 105 around 2012. I’ve still got it. 😉

When attempting to start a warm engine, the engine would start briefly but would then stop with a hell of a rumble and thump.

The problem was sorted by changing the battery.

From what I learned on here, a warm engine requires more power from the battery than a cold engine.

Try swapping the battery and see how you get on.

Good luck.

Hello,

I've had a relatively similar issue on my 2009 1.9TDI BXE.

Check the fuel pressure (right after the fuel filter).

The issue on my end was due to the cap above the fuel filter. It has some valves within it which, over time, can fail to function properly, especially when hot.

The issue itself was that not enough fuel was able to pass through the valves which caused my engine to die when attempting to start (it even died sometimes while driving).

I changed the entire thing about a year ago and all issues went away (but it took me a loooong while to figure it out).

On 23/08/2025 at 09:36, flying pig said:

The problem was sorted by changing the battery.

From what I learned on here, a warm engine requires more power from the battery than a cold engine.

The PD engine has a different start procedure to most engines. When hot it requires a high spin speed. The cpu allows any spin speed when starting from cold.

It is a well known problem from Mk1 Octavias with the PD engine. The cause is a tired battery. Replacing it will give higher spinning revs and a fast start.

On 19/08/2025 at 14:12, Alasdair1 said:

When it does it again remove fuel cap to see if theres a vaccum and try starting without cap on. When my van did it due to the wrong cap being fitted it was worse with a full tank

Alasdair

Hi. It hasn't been repeating the problem lately since stating the problem on here which is typical!! It did it once and I only let it not start once and removed the fuel filler cap. Instantly started so I'm hoping that is the issue but I need it to repeat a few times to be definite but I'll keep you updated. Thanks

On 24/08/2025 at 15:26, LaurMihai said:

Hello,

I've had a relatively similar issue on my 2009 1.9TDI BXE.

Check the fuel pressure (right after the fuel filter).

The issue on my end was due to the cap above the fuel filter. It has some valves within it which, over time, can fail to function properly, especially when hot.

The issue itself was that not enough fuel was able to pass through the valves which caused my engine to die when attempting to start (it even died sometimes while driving).

I changed the entire thing about a year ago and all issues went away (but it took me a loooong while to figure it out).

Hi .ok I have changed the battery in the last couple of years so I'm hoping the battery would last a bit longer as it's a good make. Maybe I can get it checked out on a meter

Thanks

8 hours ago, pikpilot said:

The PD engine has a different start procedure to most engines. When hot it requires a high spin speed. The cpu allows any spin speed when starting from cold.

It is a well known problem from Mk1 Octavias with the PD engine. The cause is a tired battery. Replacing it will give higher spinning revs and a fast start.

Hi

The battery is not more than a couple of years old so I'd be gutted if it's that but if it sorts it then it's 100 pounds well spent.

Thanks

On 24/08/2025 at 15:26, LaurMihai said:

Hello,

I've had a relatively similar issue on my 2009 1.9TDI BXE.

Check the fuel pressure (right after the fuel filter).

The issue on my end was due to the cap above the fuel filter. It has some valves within it which, over time, can fail to function properly, especially when hot.

The issue itself was that not enough fuel was able to pass through the valves which caused my engine to die when attempting to start (it even died sometimes while driving).

I changed the entire thing about a year ago and all issues went away (but it took me a loooong while to figure it out).

Hi thanks for the information. That's something I'll investigate that potential issue. Was it an expensive thing to change?

Thanks