VS 5L won't start hot??

[oosty85]

Hey, as the titale says I'm having a problem with my vs 5L not starting when its been running for a while..the only way to make it start is to give it throttle and even then it stutters and wants to stall for the first 20 seconds.

could this be incorrect spark plug gapping?? mods to the engine (if this helps) are:

stage 2 cam & injector package, extractors.

it cranks over fine, but wont start. SUGGESTIONS PLEASE!!!

cheers, josh.

 

[lukey383]

did you have it tuned after the mods?

 

[Brett_jjj]

Try doing an error code check to see if that shows up anything.Heres a link to a post that show you how, if you dont already know how to do this ,Its easy to do,and only takes a minute.Also if no error codes show up, then check the hall effect sensor (HES) in the distributor,and the actual ignition module itself.Also,does it blow any black smoke when it finally starts up when this happens?
https://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307

 

[oosty85]

hey mate, i've been changing plugs and leads all afternoon and still no change after it warms up.. and yes it blows HEAPS of black smoke because the only way to start it hot is by pumping the hell out of throttle!!

what about spark plug gap?? my previous cars had the exact same problem (s15 silvia) and didn't start hot until i gapped them more.

i will go over your error code attachment now

 

[oosty85]

oh and i only bought the car recently and i dont know if it got tuned..but there must be a simple reason why it runs perfect apart from 'hot start'

 

[Brett_jjj]

Do the error code check in the link I posted above to see if theres anything up with any sensors etc.

 

[oosty85]

i did the error code check and i got a 2 or 3 flashes of "12" which is OK from what i've read. and then it would do another 2 or 3 flashes of "16" which is VOLTAGE UNSTABLE???

i also put my ignition module in the freezer for 10 mins to cool it down because it was untouchable after 5 mins of idle.. still didn't start even when that module was stone cold!! (would this freezer test even work??)

 

[BlackVXGTS]

DTC 16 is engine coolant temperature voltage unstable. Replace your coolant temperature sensor.

 

[Brett_jjj]

The coolant temp sensor is most likely the cause of the problem then, seeing its temperature related. With the temp sensor not working, the ECU doesnt know what temperature the engines at, so it doesnt know the right amount of fuel to inject into the engine etc so it can run properly.

 

[Vee-ard]

leaking injectors?