Random stalling issue with vn 304

[lb9]

Hello brains trust, I am experiencing a very annoying issue with my 304 where it randomly stalls out (like someone has turned off the key) while driving. It is run by a haltech platinum gm sport ecu. I have replaced the following - dizzy (twice, thinking I had bad luck with hall effect sensors), coil, ign module (tried 3 different ones), fuel pump filter, and regulator. Pressure is steady at 45psi. It's a very weird issue where it will drive fine for maybe 10 minutes, die and then it will start straight back up again like nothing's happened. It will run for another 5 minutes before stalling again, and after that it's at random. I have logged the stalling with the haltech and all sensors seem okay. Really lost as to what this could be and its doing my head in.. any ideas?

 

[MikeC]

Fuel tank vent? Coil HT lead?

 

[Deuce]

Battery clamps are worth a check. I've had a dodgy clamp before and it caused similar issues.

 

[lb9]

Fuel tank vent? Coil HT lead?

New lead with new coil. the motor is in a gq patrol.. so the fuel tank vent is the standard setup that goes up to the charcoal canister. fuel pressure doesn't drop when the car stalls. its a hard cut on ignition i just cant find where the problem is.

Battery clamps are worth a check. I've had a dodgy clamp before and it caused similar issues.

battery terminals are tight. accessories stays on (doesn't flicker or anything) when it stalls. plus, the ECU + coil are powered off a secondary battery. ECU doesn't lose power either.

 

[VS 5.0]

Do you have any way of reading error codes ?

 

[lb9]

Do you have any way of reading error codes?

No codes pop up per say, but I can view and monitor in real time what all sensors are doing and log it. everything looks to be working fine until it stalls. nothing in particular goes out and triggers the rest to stop. the logs look the exact same as if someone was turning the motor off.

 

[VS 5.0]

Checked earths ?

 

[lb9]

Got 3x 50mm earth straps from battery to body/engine/bus bar. coil and ecu earths are to bus bar. I have wiggled every single wire in the car trying to get it to stall to see if there is a split cable shorting out but no avail.

 

[MikeC]

EFI relay dropping out?

 

[lb9]

weird thing is, if I remove the efi relay while the car is running, it stays running. clicks after the car has stalled though.