vs statesman ls1 cutting out!

[pma9193]

hi first post here, i have a 96 statesman that has had a ls1 put in it.. it has a t350 beefed up g/box, but ive had issues with it cutting out (literally as if some one has turned the engine off), but starts and runs fine after. the ls1 has a mild cam, exhaust and mafless tune

it used to happen every once and a while and only once in a driving session. but recently in mornings on way to work as im driving along it would try to cut out or would cut out but save it self from dying. this would usually happen when the engine was still abit cold. i used to just let it idle for 5 or so minutes in the morning and it would usually be fine after that.

i took it to a mechanic and they recommended a performance shop as it may be a tuning issue. conversion was done at street torque in perth, i decided to take it to wa performance, the bloke had a quick look at some of the settings and noticed alot was incorrect. he dyno'd it a few times but the engine wouldnt cut out and it ran fine (WTF!). i got him to re-tune it anyway and replace 2 o2 sensors that were f***ed.
he did say that he noticed the heater circuit for the o2s had wired up be we both didnt think it would cause cutting out.

it was fine for about aweek after it got tuned but then the same process repeated. would just cut out once every now and then, and then would cut out and save it self while actually driving, and now when i go to when i go to warm the engine up in the morning i cuts out. like literally shuts off
then it will start up fine and cut out again. I repeat this sometimes twice or sometimes 10 times before it runs properly. sometimes when it cuts out after idling it does run a bit rough, but the evens out. (or cuts out)

im hoping that now it cuts out at idle aswell it may be easyer to troubleshoot! its such a pain in the ass. sometimes it runs fine straight away, or it dies, or runs rough then dies, or runs rough then fine

anyone got any ideas or similar experience of what may be going on here, im completley stumped dont even know where to start!!

cheers guys!

 

[SavVYute]

Crank angle sensor :thumbsup:

Typical symptoms. Soon as they warm up a bit they fail, then start working again after they've cooled a bit.
But check the wiring connections to it first. Make sure they're tight.

 

[pma9193]

Hmm, this occurs when the engine is cold but I.e first thing in the morning. I do believe the crank sensor has been replaced since the conversion had be done anyway though..
Possibly wiring to crank sensor maybe?? I'm not sure if fuel pump had been upgraded from 5l yet either but I'm not so sure it's a fueling fault, as it starts virtually straight away after cutting out?
Thanks though I will deffinatley have a suss out of the crank sensor!!

 

[Cpt Awesome]

Fault could be induced by heat or fault might be sensitive to load. Keeping that in mind there's a few other items that could cause these symptoms. Throttle position sensor, coils, not sure if they have some sort of ignition module like the 5L but if it does it probably needs to stay cool and if it's transistorized those thing break down over time and display little sign before failure. Those are a few that I'd be testing by sounds of it.

 

[luckyvt94]

My girlfriends mum had the same sort of problem. Was doing exact same as yours. Took 3 months of changing parts and realised that a wire for the crank angle sensor had broken. Patched it up no problem since

 

[pma9193]

Cheers guys will have a look at crank sensor wiring for a starting point I think!

 

[pma9193]

hmm been having a play around after work on it, nothing found as of yet

dont know if this points anything obvious out just yet, but also sometimes when i stab at the accelerator it cuts out once ive backed my foot off (basically like a quick rev, let foot off, cut out)....

 

[pma9193]

Fault could be induced by heat or fault might be sensitive to load. Keeping that in mind there's a few other items that could cause these symptoms. Throttle position sensor, coils, not sure if they have some sort of ignition module like the 5L but if it does it probably needs to stay cool and if it's transistorized those thing break down over time and display little sign before failure. Those are a few that I'd be testing by sounds of it.

had a scanner on it today, showed codes for;
maf sensor -tuned out
vehicle speed sensor - also been tuned out
and EVAP Emission purge solenoid'

diagnosed the purge solenoid to be stuck - was running it plugged and unplugged (harness) revving the engine and it would either want to stall or completely cut out
removed solenoid and revved engine and ran lke a dream!
just going to plug the port in throttle body and then see if my issue is fixed. i have a feeling the issue is deeper than this but fngers crossed.