Overfueling identification & correction

[peterlonz]

Hello,

1996, VS Series II, Commodore Exec. 125,000Km
In use as daily drive, it starts & drives well, but fuel use has increased & exhaust tailpipe shows soft substantial black carbon deposits.
No obvious oil burning.
My guess is fuel is too rich but I am unsure how to easily confirm this.

If I am correct what is the best procedure to remedy this.
I am considering new oxy sensors (2 required I think), new fuel regulator & tested & cleaned injectors.
What other components might need replacement, & what else may require checking.

Very much appreciate any help & suggestions.
Thanks

 

[deserthead]

o2 sensors!

 

[LAP004]

coolant temp sensor can also cause them to run rich

 

[Bowen]

You can take off the vacuum hose for the regulator and smell it if it smells like petrol (the regulator that is) then the diaphragm is busted and you'll need a new one otherwise I wouldn't replace it if its not broken O2s are a great place to start especially the age of your car I would almost say if you have no record of them being replaced the might be originals!!

 

[peterlonz]

OK guys,
It looks like I need oxy sensors.
How do I identify the correct GM part no for this vehicle and
what is the best source of OEM quality equivalent sensors, best deals usually From US?

Many thanks

 

[deserthead]

I just replaced mine again after killing my old engine. (Water through the exhaust).
I got genuine ones from Holden, $88 for the pair.

You should need four wire ones. I prefer genuine and you will probly find most people here will recommend genuine.