VT 5L Error code 31 theft deterrent but VATS are off

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
Jackson.
Posts: 26
Joined: Mon Jul 13, 2015 3:03 am
cars: LX Torana

VT 5L Error code 31 theft deterrent but VATS are off

Post by Jackson. »

Hi, the car was running, rough but running. Playing with the distributor to adjust timing and the car died.
Will no longer start no matter what.
Spark is getting to the plugs and the injectors are working as far as a multimeter is concerned.

Upon checking the error codes, error code 31 are appearing on 2 different memcals with VATS turned off.

What could be causing that?
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 2:57 am

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by 'quipt4it »

Hi Jackson
Check if the plugs are wet. No chance of start if saturated.
Code 31 would disable fuel pulses.
Try pressing unlock on key before start attempt (if plugs are clean/ dry).
Is there a delay between key turn and starter engage.
Re-seat connector at the dist., you may have bumped it.
Did you clear codes between memcal checks.
Jackson.
Posts: 26
Joined: Mon Jul 13, 2015 3:03 am
cars: LX Torana

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by Jackson. »

'quipt4it wrote:Hi Jackson
Check if the plugs are wet. No chance of start if saturated.
Code 31 would disable fuel pulses.
Try pressing unlock on key before start attempt (if plugs are clean/ dry).
Is there a delay between key turn and starter engage.
Re-seat connector at the dist., you may have bumped it.
Did you clear codes between memcal checks.

Its not in a commodore so no BCM or normal key
No delay from ignition to turn for start
Have checked distributor connection
Cleared codes.

Will check if plugs are getting wet

How can i test the hall effect sensor
brindo
Posts: 333
Joined: Sun Jun 28, 2009 11:43 pm
Location: Western Queensland

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by brindo »

If you are confident you have spark and fuel, is the fuel pump running and pressure ok?

Not sure on testing the hall effect sensor, but is it a genuine distributor or aftermarket? I had a Fuel Miser one that wouldn’t run right. It should bring up a different code though.

Also maybe check the wires in the connector to the ignition module to make sure they haven’t pulled out. And is the ignition module ok?
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 2:57 am

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by 'quipt4it »

Make sure the ALDL test terminals bridged are 5+6.
5+12 will bring up error code 31, but relating to ABS module LOL.
There is a test for the hall (Holden service manual), but it involves an ammeter and DMM.
Jackson.
Posts: 26
Joined: Mon Jul 13, 2015 3:03 am
cars: LX Torana

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by Jackson. »

Yeay bridging 5 and 6

Its an aftermarket distributor, couldnt find a genuine one anywhere. Have tried a different ignition module.

Definitly spark with a spark tester. Was confiident i had fuel but im going to pull an injector use some wires between injector and plug to visually see it fire.
brindo
Posts: 333
Joined: Sun Jun 28, 2009 11:43 pm
Location: Western Queensland

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by brindo »

If its got spark, and sparking at the right time, must be fuel I guess.
I don’t know the brand but got a good quality distributor from EFI Hardware. Was delivered overnight too which was exceptional service.
Jackson.
Posts: 26
Joined: Mon Jul 13, 2015 3:03 am
cars: LX Torana

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by Jackson. »

Ok i pulled the fuel rail up and tried starting. On the passenger side at least. 1 injector is firing, 1 is trying to and 2 arent at all.

Now these injectors were all removed cleaned and tested about 2 months ago

Will hall effect sensors do this or do i need to look at stripping my wiring loom down
'quipt4it
Posts: 675
Joined: Sun Oct 28, 2012 2:57 am

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by 'quipt4it »

It sounds odd that there is one injector pulsing.
A code 31 would/ or should cut them all.
I would pulse one of those non-firing injectors with 12v just to be sure it's OK.
Only very briefly touch on + and - with jumpers, as they will overheat if held on. A distinct 'click' should be heard.
Hall sensors are very unpredictable, sometimes a code will set, sometimes not.
Another thought, you only found there was a code set when it was a no start. The code may have even been set when it was running?
Also, what was the longest you've had it running.
I've also heard bad things about Chink distributors, however RAE brand are probably the best of these. Some swear by them.
kojab
Posts: 445
Joined: Sun Mar 22, 2009 1:52 am
cars: VT V6 supercharged in a corolla
Location: Sydney

Re: VT 5L Error code 31 theft deterrent but VATS are off

Post by kojab »

If Code 31 is set it will not turn off injectors providing Vats is disabled in the bin. If you don't like seeing Code 31 just turn Code 31 off in the bin

The VT 5L uses a special distributor. From memory it has one extra wire which supplies a cam signal to the PCM. Can't remember if no cam signal negates start up or over fuels engine. Yes I am getting old.

Were your injectors professionally cleaned and tested? I have often come across customers who have had plastic bodied injectors serviced only to find they have been totally destroyed. Possibly over pressured during flow test.
Have heard but not confirmed that plastic bodied injectors cannot be serviced successfully like the steel bodied injectors . I know most places will service them.