vulnax999

iTrader: (7)

Had a problem, now seems worse than thought!

For months the water temp gauge on the dash dropped to cold when the revs rose above 3000 - 4000 rpm! Odd, so ordered new sensors.

Car was running rich, getting worse to very rich - so changed Lambda.

Car is mapped and running Apexi PFC so sensors can be checked on it.


At new lambda ( when hot ) get the "right " volts, around 0.84, 0.86. At the SAME time on the Apexi O2 semsor value I get 0.6 to 0.66! AFR gauge shows very rich ( ties in with lambda voltage! ).


So question is, looks like I have a wiring fault, would it be a particular loom run or bad earth?

For info, the car has multi earth set up wiring to both inlet manifolds, block, gearbox/starter, both wings, ECU mountings and case.


I'll check earth continuity from various points against battery earth to try and identify where there is a break/poor connection.


Any one got a clue where to start or had similar?

Car is MY94 JDM wagon, quite modified now!

vulnax999

iTrader: (7)

Checked battery earth to all engine bay points, some loom earth pick up points and all have good continuity.
Still to try and check ECU earth and dash earth, if I can get into it!

Checking lambda sensor output voltage against PFC and there is a 0.2 volt difference across the range.

Would this be possible for a poor earth??