False Crank Sensor Triggering

[alistai_Westy]

It looks like im stuffed.

My only suggestion is to plug another ECU in and see if the problem is hanging around like a bad smell.

Anyone got one to try?

Sparrow:

Can you help with this?

Cheers

Al

[Rob Stevens]

Can you try a new dedicated +12v ecu to battery supply just for testing.

[stevieturbo]

Can you try a new dedicated +12v ecu to battery supply just for testing.

Not a bad idea.

And perhaps even a power supply completely isolated from the car itself unless that's what Rob means.

ie a battery sitting away from the car, and in no way attached to the car, just the ecu.

[alistai_Westy]

Good idea.

I will pull the battery out the car and supply the ecu with two new leads and then put an electrical load on the battery and listen for the injector firing.

Cheers chaps

[alistai_Westy]

I've found the root cause of the problem. This is what I did.

I left the car battery in place and used it to power the cars electrical loads as normal.

I totally removed the ECU and loom from the car except the crank sensor. I then powered the ECU from another battery. The two systems are now separate.

The fault still remains.......

I then disconnected the crank sensor and plugged the loom connector into a spare sensor that I have. I moved the sensor around the car. I found that the fault appears when the sensor is less than 12 inches from the car battery.

The crank sensor on the engine is less than 12 inches from the battery (in its normal position on the car).

Does anyone know how to shield the battery? What materials etc?
I don't have another position in the engine bay for the battery. I could reposition it in the rear of the car but don't really want to do this.

Chaps, thank again for all your thoughts and help.

Maybe this pain will help someone else out there at some point.

[corsaboy]

Euhm..... I know that these sensors could be sensitive but not so much..
Is the shielding correct of the sensor and/or correct wired to the DTA??

[stevieturbo]

Weeeiiirrrdddd !!!

Try a different battery in the car ?

Try a different sensor ?

Are you using proper twisted shielded wire ?

Could you switch to a hall sensor ?

[ignitionautosport]

Sensor mount vibrating... could be small voltages are filtered out when running but treated as triggers when not. More thinking out loud and not electrical related, but heard of it happening.

[Alex DTA]

I'm stumped.

Worth Googleing to see what others have done?

[lumley32]

is the battery in a box of any sort? if not then try a grounded sheet of aluminium in between.

i cant see that a battery thats working correctly can make any inductive noise could be a lose plate inside?