Engine Malfunction Light.

[steveskeggy]

Hmm, noticed this morning that the engine malfunction lamp was on.

I changed the Battery last week as the old one had let me down for a third time, so I put the fault down to something not liking the change.

I tried disconnecting the Battery, this worked for a while, but after 4 miles the light was back on.

Then I read that the light comes on if the car is out of petrol, I also read that sometimes a loose petrol cap can cause it to come on, as well as the VSC light.

So I filled up, the light was still on, however when I disconnected the Battery again the light stayed off, did a 10 mile run at various speeds and it was still out, and continued to go out after several restarts.

I didnt think that the fault was serious, because the car drove as normal when the light was on, in fact if it had`nt been for the light, I would not have known anything was wrong!

Any ideas what happened, or did my car have yet another brain fart.

Not very impressed by the electrical gremlins on the 430.

[steveskeggy]

Drat, after 2 days and 30 miles its come back on again.

Took the lead off the Battery again will leave it off overnight.

Wouldnt mind if there was a misfire/noise/any other odd event, but its just a light coming on. :tsktsk:

[Haylands]

Hi

To find out what it is use a fault reader to pull the fault code.... they are pretty cheap on eBay....

Pete

[steveskeggy]

Okay, got a reader, and its saying P0155, which is the Sensor Heater Circuit Malfunction (Bank 2 Sensor 1).

So, now I know what it is raises some more questions.

1. Why does the car still drive as it did before, the fuel consumtion hasnt changed, starts first time etc etc.

2. When I replace the sensor, will a universal sensor fit, or are the threads different, or is there some other lexus reason why I cant fit a none Lexus part?

3. Is this sensor a 4 wire jobby? as this one http://www.lexls.com/tutorials/EFI/mainoxygensensor.html

4. How much of a cow is this job going to be, I had a quick look this evening, and it seems a bit tight if I am looking in the right direction (Drivers side next to the suspension turret).

Of course the first thing I will do is check the fuses.

Thanks