VS V6 cranks over slowly when hot

[Krilnik]

Starts fine first thing in the morning or when i hop in it after work. Cranks over fine. No dramas.

But if i cruise around town, go to the shops etc and have been driving for a while its REALLY hard to start. Sometimes she won't start at all. It cranks over really really slow. Usually does fire up after cranking for about 45 seconds though.

Have tried another battery - no difference.

Anyone have any ideas?

 

[Brett_jjj]

Try to get the highest CCA (Cold Cranking Amps) rated battery you can.I had a 420 CCA battery and replaced it a few weeks ago with a 600 CCA battery, and it winds over fast now.It used to wind over really slowly sometimes,mostly when hot..The battery was AC delco brand and cost $120.Also check that the earth leads that go from the battery to the engine block and body are clean and tight.Some people get thicker wire ran to the starter from the battery,this obviously helps get more power from the battery to the starter.

 

[Krilnik]

Thanks for the reply.

My mechanic wants to change the starter motor. Does this sound like a starter motor issue?

 

[Brett_jjj]

No,If it cranks over fine when its cold,and is only effected when its hot,then Id say its more to do with the battery leads,lead connections, or the battery itself having too low of a CCA rating.The main lead that goes to the starter is too small, and cant handle the load the starter puts on it once it gets hot..And as the lead gets hot, the resistance increases in this lead, and this is why it cranks over slower once its hot.More resistance in the lead equals less current reaching the starter.Thats why a lot of people run a thicker wire from the battery to the starter to overcome this problem,its a very common problem with these cars..Ive found that by making sure the earths and connections etc are all clean and tight,and by fitting a high CCA rated battery, that I dont have to run the extra wire.I have ran extra earth wires to the engine block and the body though from the negative battery terminal..

 

[admir87]

I had a similar thing, in the morning would crank fine, but once it was driven for abit, it would crank extremely slow if the motor was still hot. A member on here told me to change the starter motor, and it sure fixed the problem.

but it also could be other things too, such as earth wires loose, etc, like brett mentioned

 

[JAAV]

If you still have the old Bosch starter( not reduction drive) It could be the armature, new starter, old battery leads will do the same.
The battery when cold will be the hardest time to crank as once the engine has been running it will have an extra charge and warmed up. So a bigger battery will only cover up the problem un till it gets worse..

 

[justbad4you]

Yeah leads cause all sorts of probs when not workind as should be

if you still have the old bosch starter( not reduction drive) it could be the armature, new starter, old battery leads will do the same.
The battery when cold will be the hardest time to crank as once the engine has been running it will have an extra charge and warmed up. So a bigger battery will only cover up the problem un till it gets worse..