1. Home
  2. Car Maintenance
  3. Lambda / O2 Sensor Questions.

Lambda / O2 Sensor Questions.

Hi Guys

I'm new to this petrol engine stuff so bear with me (I'm more used to old fashioned diesels)

Car is a Vaux Combo Van 1.6 PETROL/LPG. Recently i had the rear section of the exhaust replaced, then as per normal a month later the front section developed a small blow near the flexi and given that much KERCHING was required (odd ball engine/vehicle combination) it had to wait for a couple of weeks.

During this period the engine warning light decided to come on i suspected due to the exhaust flow disruption, a couple of days after i made a temporary repair with exhaust paste the light went out.

Now, a few days after i have had the section replaced the light has come back on (as i changed gear and the revs fell) i have had the codes read, and the two current faults logged were o2 Sensor and EGR.

Before i dash out and replace one, or the other is it likely that the systems are just re-learning the proper settings and will sort themselves out.

Is one or the other a more likely culprit?

Whilst i can find the o2 sensor sticking out of the exhaust I'm a little more befuddled by the location of the EGR, on previous cars this has been a noticeable branch from the exhaust to the inlet manifold, but on this i see no sign? - That said haven't had change to look properly in daylight.

Are there any Gotchas with the sensors? I seem to recall the OEM / Branded units are recommended as the cheap ones can be s**te, is this true?

Whilst being a tight arse I'd rather pay twice as much and it last three times as long!

Finally, I sometimes notice that the van hesitates before accelerating and sometimes feels like it is ever so gently surging periodically when tickling along at 40mph could this be related?

All thoughts welcome

Bloody petrol's....

TIA

Tom

Incidentally, the annoying rattle i was struggling to find a few weeks ago turned out to be a loose pinch bolt at the base of the steering column.

Reply to
Tom Burton
Loading thread data ...

Tom Burton used his keyboard to write :

A very nice man from the AA diagnosed an EGR as faulty on diesel engined version I had. That was mounted somewhere close to the radiator and did not seem to be too closely connected to the exhaust system. It looked similar to smaller version of none pre-engaged starter motor solenoid.

Reply to
Harry Bloomfield

Before you buy another O2 sensor whip the old one out and give the sensor a good five minute blast all over with a blowtorch, especially in the three cutout gaps. That sorts out the ones that are clagged up. You can even wire up a multimeter to it while you're doing it and you really notice a big difference in the reaction speed.

Si

Reply to
Mungo "Two Sheds" Toadfoot

Nedavno Mungo "Two Sheds" Toadfoot napisa:

I have read somewhere that connecting a multimeter to O2 sensor will kill it. I do not know if that is correct, but you may google for it.

Reply to
Yvan

no, of course it won't.

Reply to
Mrcheerful

I don't see how - it won't be putting anything into the sensor.

Si

Reply to
Mungo "Two Sheds" Toadfoot

Well it would put in a small voltage to see what the resistance is, usually

1.5volts, certainly not enough to do any harm. If reading the voltage output then nothing goes in.
Reply to
Mrcheerful

Zirconia sensors output 0-1v according to O2 concentration and can be tested by voltmeter set on a 0-2v scale. Titania sensors don't work without a supply current so will show 0v.

GM are one of the makers that have/do use Titania.

The rule of thumb way to tell the difference is Titania sensors have a red wire (some have yellow). Nissan Zirconia 3 wire sensors break this rule by having a red wire on the heater.

Reply to
Peter Hill

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.