hot start problem ibiza ASZ pd130

[joop200789]

mine dint do it to when i first got it only in the last 5k is starting doing and ive had ot since 78k and it now on 120k

 

[mick-fr]

Thats maybe why... Mines only got 61k Still not worn in yet!

 

[joop200789]

Thats maybe why... Mines only got 61k Still not worn in yet!

its only a baby engine lol

just read this
fuel isn't injected at crank speeds below 250rpm with engine temeperature above 70'C

so thinking maybe a odd legged starter motor might not be able to turn the engine over fast enough when it higher pressure inside the engine due to heat slowing it down and also the extra heat in the engine bay creating more electrical resisstance

so am guna use this guide hear http://www.montreal-vdubbing.com/forum/viewtopic.php?t=43 in next couple of days see if it improves any

 

[canis_lupis]

Hi, I have known crank sensors to break down only when hot, well worth considering this and using vagcom to try and compare cold with hot readings from crank sensor. Also just because the battery shows 12v when not under load does not mean its good, check the volt drop on crank it should still hold at around 10-11v whilst cranking, if not it may be droping a cell when warm, plus is the battery the correct rating for the car? eg does it have enough cranking amps?

 

[Lee g]

mine starts straight off the bat when cold and also struggles when hot sometimes, didnt think it was a big problem though.

 

[digby130?]

so have identified two more things that could be wrong:
outside air temp sensor
and coolant sensor

i presume the coolant sensor is different to the engine temperature sensor?

cheers guys for all the replies! hoepfully i will find the fault soon lol!

 

[digby130?]

@ lupis, battery is all ok!

 

[joop200789]

went to do a drop test on my battery last friday couldnt not get a connection on the battery so i took the terminals of got some 240 sand paaper and roughed the terminals up and the battery poles (on the todo list fo ages)replaced them did the drop test battery was strong needle barley moved (7 year old battery according to SH)

but since i cleaned the up ive only had the hot start problem once (but lights must have been left on for 15 min)and ive done 400 mile since then. still not a fast as firing up when cold but now its only taking 3 or so cranks before firing now

have a check of the poles and terminals clean them up and also check the starting and charging cables for corrsion and over all resistance

 

[canis_lupis]

Good call joop, resistance test is good but voltage drop when under load is the best way to test as bad resistance doesnt always show up when not under load, but any significant corrosion on starter positive or earth cables would give slugish turnover! To do this set multimeter to volts dc, place red to the battery positive then the black to the starter connection, turn engine over, the reading you get is the amount of volts that have been lost over that circuit, it works for earth too! Using this method you can narrow it down to a specific connection, once the engine starts the reading will change as the circuit is no longer loaded. hope this helps!