supercharged vx starting and general driving issue

[mel83]

Hi,

I have a 2000 VX commodore S supercharged auto. for the past 12 months its had a starting issue when cold. it will crank but wont turn over until the power train light goes out. i have replaced the crank angle sensor as that is what comes up when you plug it into a computer but is not the issue as it has been replaced three times. i've replaced the coils, ignition module and throttle position switch. at the same time this happened it has also developed a problem with the trasmission where it will not change from 3rd to 4th gear properly (ie will slip as it goes in) but it mainly does this in heavey traffic when i have to be on and off the throttle, when it does finaly get in it will labor until i kick it down to third. it over revs as it changes from 3rd to 4th. when driving on a flat road at a steady speed it will drop out of 4th and back into third then up to 4th again for no reason, it's deveopled an intermitent ticking noise when it goes from 3rd to 4th, and sometimes it will crunch when it engages 4th. When i replaced the throttle position switch it helped but not by much. my mechanic and the auto elec thinks its either the bcm or the ecu, he's leaning towards the ecu but wants to do more research so i dont waste money on replacing it if i dont have to, also latley when its been plug into a computer alot of codes come up that aren't related to the issue when it was cleared the car ran fine for a day but has gone back to what it was doing. If any of you have had or heard of this issue advice would be apriciated. thanks

[Tree cutter]

I would be checking the wiring that goes to the crank angle sensor if it keeps coming up as a fault after you have replaced the sensor. There could be a wire that has rubbed through the insulation so it only shorts out at certain times when it touches. Sounds like a hard one to find. Is the ticking noise on gearshifts coming through the radio or does it sound like it is coming from the trans. Your auto electrician should be able to check with a multimeter to see if one of the crank angle sensor wires has shorted or is broken.

[mel83]

The ticking sounds like it is comming from the transmission. its intermitent. if its going to make the ticking noise it does it when the car is under load.

[mel83]

my mechanic tested the wiring to the crank angle sensor after it was replaced for the second time and all seemed ok.

[boby]

leaning towards computer hey
because the trans and engines are not working right and it's giving errors which have nothing to do with the problem,,,, think somes stuffed thier
but then again if it ran fine for the day the computer, might just be getting some random signals making it do wierd crap, maybe over look the comps wiring looms might have some contaminates causing unusual inputs. water, or condensation whcih mayhave ended up their.
has it had a sterio installed or re-adjusted reciently ?

[mel83]

no, stereo is the original and hasn't been adjusted.

[mel83]

Just thought i'd give an update on the starting issue I've had with my VX. Issue has been fixed. it was a couple of contacted relays for the DFI module and transmission.