Doesnt start once hot

[52GTIPETE]

I will agree with S174 as because the coolant sensor is not working correctly the ECU cannot tell if the car is hot or cold and to put the choke on or off. Had the same problem on a 1.4 polo. Coolant sensor solved it.

[52GTIPETE]

Also missed the bit about slow cranking. Doh. 

[jamie16v]

Thanks for replies,

I have changed the coolant temperature sensor last month as i used to never get a reading on the clocks before.

When i try to start once its warm it does slightly crank very slowly and after around 3-4 tries it stops cranking.



Also where is the knock sensor located so i can investigate

Thanks

in that case it sounds like your battery is knackered. it could also be the rectifier in your alternator not charging the battery!...
knock sensor is bolted to the outside of the block, looks like a ring type plug with a bolt going though the middle of it.

[jazz5000]

Battery is uprated from a BMW X5 for my sounds.
voltage is at 12v when i attempt crank

[jamie16v]

hmmm....what voltage do you have when engine is running?

[jazz5000]

14.3v roughly

[jamie16v]

ok, so you got 14.3 volts from alternator, 12v when engine not running, it turns a couple of seconds then dwindles away?..

[jazz5000]

First time you start car it fires up after few seconds,

Once its hot and you stall    or just turn engine off and try to start 5-10 minutes later it cranks very slowly like maybe 1 turn per second. After few seconds of this it will stop and not crank.

Now you mention it , it does sound like a flat battery as in the sound it makes.
But cant be flat as voltage is 12v and ignition lights and music dont cut off, and it will start no problem once it cools down.

Had this happen as well the other day in a car park. Had to get help and get the car pushed into the bay, It then started after i got it in the bay    But turned off the engine and tried to start again and it wouldn't start. Came back 15 minutes later and it started no problem

[jamie16v]

have you checked the cable and connections going to the starter motor for corrosion?.
also worth checking the earth straps etc.

[kingaz]

Might be unrelated but my escort turbo did this..found out it was missing a heatshield and starter motor was getting to hot