VL Commodore intermittent fault

**Bobby Slogger** · 12-01-09, 09:44 PM

Hi all,

didn't know where else to turn to so I thought I'd try here.

My father in law is having problems with his VL commodore. It drives fine. When he turns the engine off, sometimes it won't restart. This is after a 15-20min break if not longer.

The problem has happened on warm or cold days.

We bypassed the immboliser but the problem is still there. We've also replaced the CAS (twice) but the problem is still there.

I think the problem is electrical but it's so intermittent that the Auto Electrician can't find the fault.

Does anybody have any ideas or experienced simmilar faults? Other than this, the car runs brilliantly.

Thanks,

BS

**malrose** · 12-01-09, 10:13 PM

Originally Posted by Bobby Slogger

Hi all,

didn't know where else to turn to so I thought I'd try here.

My father in law is having problems with his VL commodore. It drives fine. When he turns the engine off, sometimes it won't restart. This is after a 15-20min break if not longer.

The problem has happened on warm or cold days.

We bypassed the immboliser but the problem is still there. We've also replaced the CAS (twice) but the problem is still there.

I think the problem is electrical but it's so intermittent that the Auto Electrician can't find the fault.

Does anybody have any ideas or experienced simmilar faults? Other than this, the car runs brilliantly.

Thanks,

BS

I had the same problem with a VT. It ended up beeing the crank angle sensor (located behind the harm wheel), but then again it could be anything..

It only occured when the engine was warm and then after that was very intermitent.. Would not start for hours, then in the morning would start..

Sorry, I dont know how to check these.

Cheers.

**Bobby Slogger** · 12-01-09, 10:15 PM

thanks for the note. It's just that we've changed 2 sensors in 1 year. Very unlucky to have 2 of them go so quickly.

**rob916** · 12-01-09, 10:25 PM

sounds like the crank angle sensor to me.
This is on the dizzy on a vl.

**Godzilla** · 12-01-09, 10:33 PM

LOL let the games begin.

The VL's #1 problem is the crank angle sensor.

Yes you have changed it but read what im about to write carefully, been there, done that.

Firstly the biggest cause of lack of spark comes down to the CAS failing due to bearing dust getting over the sensor, causing it to 1/ overheat and fail, 2/ the dust blocking the pickup plates, 3/ the worn dizzy bearing allowing the plate to rub up against the CAS and bugger it up again.

Solution, take the dizzy out and check the bearings for wear allowing shaft sideways movement. Also eyeball the CAS for contact marks, if found replace it again.

Next, the CAS can go haywire if the car has bad ignition leads that arc, this will send it beserk if not cook it.

Check your ignition leads for corrosion, make sure you check the coil main line in the coil and dizzy, you may find it full of green corroision, sand it out of the coil and leads.

Check all your electrical plugs, disconnect, look inside them and reconnect incase you have a bad connection. Heat under the hood builds resistance in your electrical system.

Connect a jump lead from your negative terminal to the block on bare metal, a bad earth connection will cause the ignition system to fail most noticably when hot.

When someone tries to start the car hold and move the plug at the airflow meter, these are known to get dry solder/cracked connections internally, it can be opened and resoldered if playing with the plug starts it.

When trying to start the car open the petrol tank and listen in the filler nozzle, when the ignition switch is turned you should hear the fuel pump start. No sound? Whack the tank from under with a rubber mallet to kick the fuel pump back to life.

Thanks for reminding me of the hours of hair pulling ive done on them.

Ps all VL Turbo owners carry a spare CAS or convert it to MSD ignition. LOL

**LeroyPatrol** · 12-01-09, 10:57 PM

I had 2 crank angle sensors go faulty in a matter of months a few years back in a VT!

Leroy

**hillbilly** · 12-01-09, 11:09 PM

its a common problem with the VL's (and all commo's by the sounds of it)

My folks had 3 done in 1 year, so it's very possible that this has happened to you, do what Godzilla has written.

**Godzilla** · 12-01-09, 11:19 PM

Originally Posted by hillbilly

its a common problem with the VL's (and all commo's by the sounds of it)

And Fords, and GTR's, and Mazdas, and, and, and.....all makes of cars except Toyota's.

What stands out about the VL problem is wear in the dizzy shaft bearings aggravating the problem.

**rastus86** · 12-01-09, 11:23 PM

change the crank angle sensor as well as the 4 pin plug to it they come as a kit the boot lets in the water and dirt ...ect make sure you get a good brand there are alot of cheep crapy ones from repco bursons ect

i have had heaps of these fail don't worry how long or how many you have changed get a good brand one you wont change any more of them end of story

**hillbilly** · 12-01-09, 11:29 PM

Originally Posted by Godzilla

And Fords, and GTR's, and Mazdas, and, and, and.....all makes of cars.

What stands out about the VL problem is wear in the dizzy shaft bearings aggravating the problem.

yes maybe, but never herd of the humble Toyota 4agze having a problem with it.

Toyota's over engineering would probably be the answer.

**Godzilla** · 12-01-09, 11:56 PM

Originally Posted by hillbilly

yes maybe, but never herd of the humble Toyota 4agze having a problem with it.

Toyota's over engineering would probably be the answer.

Yes i should go back and edit that post to all cars except Toyota's.

(And i just did)

I havent seen one fail on a Toyota yet, however i have seen the pin holding the dizzy cam gear shear on one 4k-j because a counter weight lost its spring and came into contact with the distribtor housing.

Nothing that 5 minutes and a new $1 pin couldnt fix.

Gotta love them Toyotas.

**Strada916** · 13-01-09, 04:00 AM

next door had a VL and in the space of about 3 weeks he change 2 of them. Not sure what was happening but ended up buy a genuine CAS and his problem got better. This time it took about 6 months be it failed too. He ended up replacing it and then selling it.

**Bobby Slogger** · 13-01-09, 08:09 AM

Thanks all. Will get it checked carefully on the weekend.

BS

**Jack Frost** · 13-01-09, 02:19 PM

The CAS has been covered extensively, my pennys worth.. My not so young BM had a similar problem. Turned out to be a worn ignition barrel. Our very new Vectra that would not start....CAS ! Let us know how you go.

**z80** · 13-01-09, 06:05 PM

just check for spark when it fails....

that's where i would be starting...

**littlejimbob** · 13-01-09, 07:05 PM

crank angle sensor,s can be a pain , mine played up on cold starts , hot starts, also would get into violent hops while driving as well .took a very long time to trace this problem,as was very intermintent.
if it isnt crank angle sensor , i would suggest checking some simple things like the condition of fuses , relays etc, from what you have said it seams to be happening after car has been warmed up and you return to it after a short time, could be getting what you call a hot soak .it is overheating an causing a short. or computer is picking up fault and shutting down, we have a prado that had similiar problems where after a short break it wouldnt start , would have to keep trying and eventually it would start or it would start and shortly after while driving along it would completly shut down leaving you to your own devices.it was a corrided fuse for the fuel injection , worked fine on first start of day , but after second start when it heats up more after stopping it would seperate or short, when it cooled down it was fine , even toyota couldnt trace this problem properly they traced to relay replaced it and still happened 2 days later .
hope this helps

**Bobby Slogger** · 28-01-09, 09:40 AM

OK - we decided to change to distributor on the weekend (got a secondhand one from the wreckers).

Leads and sparks are new and so far, no problems as yet. My feeling is the bearing in the distributor. We'll know in 3 months.

Out of interest, my father in law is now thinking of selling the VL.

What are they worth? This one is 1 owner - 113K and in very good condition for it's age.

Thanks all for your input.

BS