Evening all.

I won’t go into too much detail until I get a bite but I have an intermittent fault code of P0130 O2 sensor on my X reg 2.0 16v Vectra. My friendly mechanic initially diagnosed the sensor but when I took it for replacement today he is now not so sure.

LMGTFY?

http://www.obd-codes.com/p0130

http://www.astraownersclub.com/vb/showthread.php?t=157798

Hmmmm……actually I had been Googling for info for around two hours before trying the good folk here. What I found was way better than your effort as well.

By the way FOYTW.

HTH

Had you have thought to tell us this in your OP, you’d have saved me the bother.

Your assumption, not mine.

so what help are you after? The fault code tells you where the problem is, and links above tell you what might be wrong. You now need a mechanic/sparky and an open wallet.

Intermittent warning lights often just mean that the diagnostic is not running on every drive cycle, or that the fault is not always there. Still something wrong though.

I remember a friendly local mechanic commenting on my Vectra’s problems before it finally expired. He said something about the wiring insulation under the bonnet getting brittle with age and heat, and causing intermittent shorts. Some of the new bits had replacement wiring with them.

In case it’s of any help.

I’m after suggestions that are a step removed from the obvious action of changing the sensor. From my Googling it has become apparent that many people have changed the O2 sensor based on the same fault code I have and it has not fixed the fault.

As an example, I found that a common fault on the Vectra is the EGR valve body and gasket corrodes which lets unmetered air enter the exhaust. The O2 sensor picks this up as a lean mixture and fixes at a lean output for an extended period. The ECU then assumes the O2 sensor is faulty as its stuck low and not switching when actually its working fine and showing a lean burn. I will be changing the gasket this weekend to rule it out.

Any help greatly appreciated.

Your assumption, not mine.

ouch! A more magnanimous response like “you’re right, I should have described what I’ve done already’ would have elicited more help even though underneath you might have thought ‘do these people think I don’t have the power of Google at my fingertips too? What kind of fool do they take me for?’

Sounds like it’s a problem with the Vectra. 😉

Depending on the cost and ability to test the sensor reading veracity I’d opt for swapping the sensor first. This effectively eliminates the sensor as a source for the fault.

That the code is intermittent makes the job more exciting: is it that the sensor is telling the truth (perhaps your gasket hunch is right)? Or is it that the computer is getting duff info – the route for more diagnostics.

In the latter case (more diagnostics) I’d take an approach like simulating the sensor response using an appropriate device – wire, resistor or something more technical like a simulation device. If the fault lies with the sensor (duff readings) or the gasket (true readings of an intermittent, real, problem) then this might help as it might quickly reveal that the rest of the system is OK and maybe the sensor needs testing/replacing. If the problem lies more ‘upstream’ in the system then this exercise will be tedious as you wait for the intermittent condition to appear.

If the fault is not a real sensor reading and dodgy O2/gasket problems and is not a dodgy sensor then wiring and connections are the next place. Ugh! Get out the meters, scopes and lots of tea.

Alternatively, if the fault doesn’t affect the car running you could just live with it. Disconnecting the warning light can be the right approach to some ‘problems’.

*I have to say that I am not an auto engineer, but have done software and system diagnostics in my time. I’ve found that stepping back, breathing in, having a cup of tea and thinking deeply is usually the best start to this kind of weekend entertainment. Hope it works out.

farmers choice… the guy was trying to help you. A bit of gratitude and courtesy would not go amiss. Sounds like you are aware of all the likely causes, just need to get on and try some of them….wallet at the ready.