Please Help. Problem with hot starting car.

Anees

Guest
Hi guys.

Hope you are well but could do with a bit of help :)

I have a 2007 Yellow Seat Leon Reference Sport - 1.4TDI.

The car runs well normally and I even had it remapped a few months ago - does go rather well after the remap.

The only problem I have is when I try to start the car when it is hot and has been running for a while. It really struggles to start up and it is annoying me big time now!

From cold it starts fine first time.

I have read about some kind of resister mod to the Coolant temp sensor which fixes this issue.

Can anyone shed some light?

Any help appreciated.

Thanks,
Anees
 

SeatDanny

Developing SEAT owner!
Oct 29, 2009
125
0
Northern Ireland, Belfast
Hi guys.

Hope you are well but could do with a bit of help :)

I have a 2007 Yellow Seat Leon Reference Sport - 1.4TDI.

The car runs well normally and I even had it remapped a few months ago - does go rather well after the remap.

The only problem I have is when I try to start the car when it is hot and has been running for a while. It really struggles to start up and it is annoying me big time now!

From cold it starts fine first time.

I have read about some kind of resister mod to the Coolant temp sensor which fixes this issue.

Can anyone shed some light?


Any help appreciated.

Thanks,
Anees


Mine also has problems starting occasionally, like ill turn the key and itl splutter a bit then pick up fine. I am interested to hear from anyone who knows :wtf: is up with that!
 

Anees

Guest
I am concerned incase it is the remap that causes it, but I highly doubt it.
 

Anees

Guest
yep I know what you mean mate - same thing with me :(

I have heard about a resister mod but can't find any info.

Anees
 

Nath.

The Gentlemans Express
Jan 1, 2006
8,619
16
EASTLEIGH, HAMPSHIRE
There are a number of sensors that monitor engine and or coolant temp (not just the one for the needle in the dash) these sensors are needed for the ECU to do it's stuff. VAG-COM would be good or go to your dealer and see if they can fine a rogue temp reading.

Another idea is to clear the water from the fuel filter.
 

JK1

Full Member
May 15, 2002
531
2
Bedford
Visit site
I've had this to, always starts first time, but when warm it sounds a bit rough.

Funny thing is it started from cold after 10 days sitting, -4c and starts instantly. But warm it always takes a bit longer (even when it was new) and now its sounding rough for those first few seconds.
 

Raz_187

Active Member
Apr 11, 2014
18
0
Thanks i got the battery and starter motor checked said it was fine, but did not clean it might try this,
 

mickey1

Guest
hot starting prob

i had a hot starting problem a few months ago in my 09 2.0 tdi FR, it was the camshaft sensor, had it replaced, not done it since
 

Speed-FReek

Active Member
Jun 12, 2013
1,110
18
United Kingdom
Assuming the starter motor is cranking the engine over at it's usual speed then this is the typical symptom on most cars of a failing hall effect sensor, usually the crankshaft position sensor and/or the camshaft position sensor. When these type of sensors start failing, the engine will still start fine when cold but becomes harder or impossible to restart once it has become hot. Let it cool right down and it starts fine again. This is because failing hall effect sensors tend to start breaking down when they get hot and as a result they then don't send the correct RPM signals to the ECU.

It's worth getting a diagnostic check done but experience with other cars has shown that the failing hall effect sensors don't always show up as faulty with a diagnostics check even if they are so bear this in mind. It depends how sophisticated the ECU sensor logging actually is.
 
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