14cux running very rich

[john hamblett]

hi all need some help please 4.0 running very rich 9.5 percent got rovergauge showing 100% for more fuel airflow seems way too low but really not sure any help appreciated

[john hamblett]

just checked lamda probes no earth on white wires and only have battery voltage on red wires when ignition on not when engine running obviously not right does anyone have wiring diagram for engine loom

[blitzracing]

The heater wires only have 12v when the engine is running, or during the 2 seconds during ignition turn on, its the same supply as the fuel pump, so if thats running the lambda heaters should have power. Its the red wire to ground. The trim shows "adding fuel" so the ECU has 0 volts from the lambda sensors, and no heater will do that, as the heater supply is linked to the lambda output. Check fuses in the 14CUX loom near the relays.

Manuals here:

https://www.dropbox.com/sh/i0acxr8nwr10ow6/AACcZ2H...


White is ground, red is heater, black is probe output. RoverGauge should be throwing fault codes for no lambda outputs.

Edited by blitzracing on Wednesday 21st August 19:43

Edited by blitzracing on Wednesday 21st August 19:44

[Penelope Stopit]

john hamblett said:

just checked lamda probes no earth on white wires and only have battery voltage on red wires when ignition on not when engine running obviously not right does anyone have wiring diagram for engine loom

A missing supply to the lambda sensors from the fuel pump relay could be caused if someone has fitted the wrong fuel pump relay

fitting this type below would cause a problem




fitting this type below would be ok



or the same relay as above with two terminal 87's would be ok

[blitzracing]

He makes a very good point here, and you will end up with a flat battery if the heaters are live with the ignition off.

[john hamblett]

thanks for info checked relay it is correct however when metering at relay if the fuel pump is running the 12v feed to relay is dropping to below 1v though fuel pump runs fine begiining to suspect fusebox issue

[Steve_D]

john hamblett said:

thanks for info checked relay it is correct however when metering at relay if the fuel pump is running the 12v feed to relay is dropping to below 1v though fuel pump runs fine begiining to suspect fusebox issue

At which relay pins were you seeing the low voltage?

Steve

[Penelope Stopit]

john hamblett said:

thanks for info checked relay it is correct however when metering at relay if the fuel pump is running the 12v feed to relay is dropping to below 1v though fuel pump runs fine begiining to suspect fusebox issue

I have never witnessed a 12 volt car relay holding in at below 1 volt, a fuel pump won't run on 1 volt

Please check again and post back

[blitzracing]

The FP relay has 12v as soon as the main relay closes when you power on the ignition, but the FP relay is then energised by being grounded by the ECU, You wont get a sensible reading unless the ECU is grounding the coil. Take two steps backwards and listen to the relays- Both the main relay and fp relay should click closed as the ignition goes on and then the FP relay should drop out after a couple of seconds as long as the engine is not started. Put your test meter on the red wire on a lambda probe to ground and you should just see 12 v for the 2 seconds the FP relay clicks in for, or permanent 12v if the engine is running.