AFR and hot oil

On the way to Llandow at the weekend my AFR guage started to behave strangely and struggles to show a reading, its normally off the scale (weak / lean) and never gets anywhere near the normal readings.

Then on the circuit I noticed my gauges showing the oil temp as 120 degrees, then on the M4 on the way home it would creep up to 120 when I went over 80mph.

Car is running fine and doesnt feel different in any way, if it wasnt for the gauges I wouldnt be bothered. But since they are there they have me worried.

Is the AFR sensor just broke and oil temp normal, or could they be related and i have a sick engine?

my oil temp was normally around 80 ish. i think it depends where your sensor is

my oil temp was normally around 80 ish. i think it depends where your sensor is

the oil is usually around 90, however on the track and the motorway its suddenly got a lot hotter.

Not sure whether its normal or if the engine is running very lean.

Its not normal for the oil temp to suddenly run a lot hotter, sounds like there was some problem on the track that has caused the sudden rise to me.

What make is the AFR and oil temp gauge? AFR have been know to go out/loose there setting, oil temp sensors can fail but not usually just change the reading by a few degrees.

Its an AEM AFR gauge and a DEFI BF oil pressure gauge.

The AFR gauge looks so unstable I think its sensor could easily be loose or faulty but cannot be certain.

The oil temp gauge should be ok, the only difference recently is that I changed the oil to 10-50 racing oil in preparation for the track day.

Have you tried the recalibrate option? Presuming the AEM gauge has this? i have had my Innovate AFR gauge occasionally go out of sync and needed to relearn O2 levels while removed from exhaust.

Having said that, if the AFRs have suddenly gone very weak, it would cause a rise in operating temps.

The change of oil would of had a slight effect on temps at the normal operating temps, as it would be 50 weight instead of 40 weight, but i certainly wouldn't expect it to cause a rise 30c.

That sounds strange. There's no way I know of for calibrating the AEM sensor/gauge. However you can test if it's still working by doing this:

http://www.youtube.com/watch?v=1mb4VmDd0ao&feature=related

That sounds strange. There's no way I know of for calibrating the AEM sensor/gauge. However you can test if it's still working by doing this:

 

http://www.youtube.com/watch?v=1mb4VmDd0ao&feature=related

Hey thats good, never seen it before.

That sounds strange. There's no way I know of for calibrating the AEM sensor/gauge. However you can test if it's still working by doing this:

 

http://www.youtube.com/watch?v=1mb4VmDd0ao&feature=related

Interesting, but if there is no way for the AEM AFR gauge to re calibrate/relearn the atmospheric oxygen level and calibrate itself to 20.9 AFR then IMO how is it going to remain accurate as the sensor wears/goes out of adjustment:blink:

I only ever use Innovate stuff, and that has to be calibrated before first use and it is recommended it is re calibrated every few months or few thousand miles in order to compensate.

Wideband sensors can suffer if they are run in an over rich environment, and so can read wrong.