VT V6 Failed to Re-Start After Stalling

[boombaby]

I couldn't be stuffed reading all the posts.

Where are the parts coming from?

That couyld be a problem replacing parts that have seen better days with crap parts?

Thanks, Lex!


> Part are ALWAYS new.

> For all other Holdens I've had, I would do GMH wherever possible.

> For this VT it's been Supercheap, Repco or Autobahn - in that order, and depending
on who's go what.

> Of course, if parts are no longer made, then guess what?

> For the key, it was BatteryWorld.


Except for the Key not much of that is particularly relevant to my first post, but
you did ask.

So far, EVERYONE has given me some good advice to go on with, which I really appreciate.

I'll try to keep it shorter in future. (Pppphfftt! Like, yeeaah!)

Regards,
boombaby

 

[boombaby]

If you have a scanner have that in the car and when it stalls scan it and see what it says.

You may have more than one thing going on.

As far as I'm aware, once the engine has started the immobilizer can't kill the engine. When you go to start the car the PCM is looking for a signal from the BCM/key, no signal, no start. Now I have had issues with "new" keys (non genuine) where occasionally the key seems to loose contact/sync with the BCM (key works on a rolling code I believe) and this might cause a no start condition or the remote lock/unlock function not to work. Clean the contact strip around the ignition switch and the little steel stub on the end of the key. Sometimes just simply locking/locking the car will reset these functions and everything is happy as Larry again.

Now I know a guy who had the same problem and couldn't figure it out, a mechanic at work looked it over and tested it and eventually found there was oil in the CAS plug that was randomly causing issues. Remove all the plugs for the Crank angle sensor, Cam sensor and DFI and make sure all are clean and no corrosion or contaminants are present.

Electrical components don't last forever. The DFI and coils don't have an indefinite life span. Consider buying a new/spare set.

One thing often overlooked is the cam sensor. This sensor shares a power and earth supply with the crank sensor. I know of one case (and I'm sure there are plenty more) where a faulty cam sensor effected the power supply to the crank sensor enough to cause a bad 18x/3x signal to the DFI and PCM causing a no run situation (the person who found it had the fancy testing equipment including oscilloscope to accurately measure sensor performance).

Unfortunately the ignition system does seem to be a bit of an Achilles heal on these engines. Having said that (touch wood), our VX is still on the original DFI module, cam and crank sensors but has had 2 sets of new coils (290xxx km).

I do agree with the others though, on the face of it, this does sound like the typical CAS sensor fault.

I also keep sets of DFI modules and coils in the garage (I've had multiple V6 cars) plus a brand new CAS sensor and have not had to replace these. I don't like Murphy!

Thanks, Immortality!

On several occasions that the car stalled on me, and my scanner was plugged in, the single error was showing. So that's one reason I'm
not ruling out the fuel filter/pump - as contributing to problems too. (Same with injector issues, I guess. It's running a little rich.)

As you may have read (or maybe not, based on other replies) this is my first DFI vehicle. It looks like - from your's and other's comments
I will be looking at the CAS, but may also/eventually replace one or more coil packs (just as part of the DFI "maintenance" thing).

Thanks for all the great tips you gave. Outstanding! (I couldn't quite tell if you went "Key" or "Chilled Water" though. It was sort of 50/50 plus
all the fabulous extras - BUT it was all good stuff to think about. Excellent.)


Regards,
boombaby

 

[Fu Manchu]

New parts are no longer assured to be good. Quality control is now done by us, not the business who made them.

 

[Fu Manchu]

examples:

Everything @losh1971 bought for his VR.

 

[boombaby]

Rob’s skills are not in every workshop.

Very interesting. Like I said I am not discounting ANY of your advice.

 

[boombaby]

i read the second part of the story, had to stop for coffee and sandwiches half way
leads me even more to crank angle sensor
anything takes a while to cool down
to prove further
jack up front of car and place on stands
pinch your ladies hairdrier, or if you are woke, use your own
heat the crap out of the crank sensor, located where wiring runs behind harmonic balancer
so hot you cannot hold onto it
then see if car starts, whilst watching mode immobilizer light
if car starts, not hot enough or crank sensor is ok
if doesnt start and mode stops flashing then crank sensor is faulty
if mode light keeps flashing the immobilizer issue

Thanks for doing that lout. (I hope you're not gonna try charging for the meal!)

That's a neat tip and technique. Sort of goes counter to the concept of "cooling the CAS". Brilliant.

Kind Regards,
boombaby

 

[Immortality]

I don't think a fuel pump dying will stall the engine instantly, rather as the fuel pressure drops it will miss, pop and fart a bit before it actually dies.

If your scanner is showing x18 missing then that points at the CAS/DFI (the x18 signal comes from the CAS but gets processed through the DFI module to the PCM).

Just remember you are dealing with a vehicle that is 24 years old (give or take).

You've written a lot and it's toooooooo much to read back through, but I would do a full service off the car so you know the important parts are good.

New plugs and leads. New fuel filter and run some injector cleaner ( I recommend this ) Oil and filter and air filter. Clean the MAF and then see what it does. For a EFI motor, one of the most critical sensors is the O2 sensor in the exhaust as it is the primary sensor to control the air/fuel ratio.

 

[boombaby]

I don't think a fuel pump dying will stall the engine instantly, rather as the fuel pressure drops it will miss, pop and fart a bit before it actually dies.

If your scanner is showing x18 missing then that points at the CAS/DFI (the x18 signal comes from the CAS but gets processed through the DFI module to the PCM).

Just remember you are dealing with a vehicle that is 24 years old (give or take).

You've written a lot and it's toooooooo much to read back through, but I would do a full service off the car so you know the important parts are good.

New plugs and leads. New fuel filter and run some injector cleaner ( I recommend this ) Oil and filter and air filter. Clean the MAF and then see what it does. For a EFI motor, one of the most critical sensors is the O2 sensor in the exhaust as it is the primary sensor to control the air/fuel ratio.

All that has been done, except for the fuel filter and the O2 things. (I am a bit worried about the Cat with the "slightly-rich" readings on the scanner, but that will just have to wait.)

I will make further comment to you, that after doing all that - the final thing being the injector cleaner - things seemed to be fixed and the car was NOTICEABLY better. It was amazing. I was driving everywhere just fine. I even did a trip halfway to Narrogin (approx 100kms) and back - with various changes in driving - without any problems at all.

About a week or two later I did a trip into Fremantle (20kms) and it choked in the city. On the way back it stalled in peak-hour traffic just prior to a busy intersection. Since then it all fell to pieces. Conks out every second or third trip.

I heard all that you said, and I am pretty determined to get on top of this a quick as I am able.

Thanks a lot for all the advice and tips (to you and to all the others).

Kind Regards,
boombaby

 

[Fu Manchu]

Still, you’ve changed all those parts. One could easily be faulty straight out of the box. New parts does not eliminate a fault.

 

[lout]

Still, you’ve changed all those parts. One could easily be faulty straight out of the box. New parts does not eliminate a fault.

especially supercheap parts
i only buy my oils from supercheap when they have a sale
as long as you know what brand you are buying supercheap are ok
but their home brands and narva stuff straight in the bin