Corsa Overheated Wire

[tomby]

Hi

The engine temperature light came on for my 2012 Corsa yesterday, i checked the coolant tank which was basically empty and noticed that there was some damage to one of the coolant pipes which you can see from the pictures.

It looks like the cable just above the coolant hose has melted/damaged the coolant hose. What is this cable? And any idea what could cause it to get so hot and melt coolant hose pipe?

I have got it booked in with my local garage at end of the week

Thanks

[drdino]

Looks like it's the wiring to the lamda sensor.

[E-bmw]

^^^^ Wot 'e said.

[tomby]

ok thanks, any idea why/how it would get so hot to melt the coolant pipe?
If it got that hot would I be right in assuming that the sensor is probably now broken?

[LimSlip]

Guessing the oxygen sensor cable has been rubbing against the coolant pipe until the insulation on the heater wires wore away and shorted. Surprised it didn't blow a fuse though.

[GreenV8S]

Are you sure it's heat damage and not just abrasion from the cable?

[E-bmw]

tomby said:

If it got that hot would I be right in assuming that the sensor is probably now broken?

Not necessarily, could be from a previous sensor that was changed but they didn't change the pipe.

[tomby]

GreenV8S said:

Are you sure it's heat damage and not just abrasion from the cable?

Pretty sure it is from heat damage as when the engine temperature light came on and i checked under the bonnet, there was smoke/heat coming from where the sensor is connected at the bottom.

The day before the engine temperature light came on the engine light "car with a spanner through" came on, I have just read - A failed lambda sensor is actually one of the most common reasons for the ‘Check Engine' light.

Is there a way to test lambda sensor is defiantly faulty? Or should i go ahead and change it ?

[paintman]

As its going into a local garage at the end of the week then you're probably better letting them sort it out.
They should be able to do a diagnostic & see if there are underlying issues.

Edited by paintman on Thursday 2nd July 10:36

[spikeyhead]

I'll guess that the cable has rubbed on the pipe, worn through the insulation on the cable and that has caused a short, which has drawn a lot of current and overheated the cable.

...or it could be something completely different.

[Oldandslow]

tomby said:

GreenV8S said:

Are you sure it's heat damage and not just abrasion from the cable?

Pretty sure it is from heat damage as when the engine temperature light came on and i checked under the bonnet, there was smoke/heat coming from where the sensor is connected at the bottom.

The day before the engine temperature light came on the engine light "car with a spanner through" came on, I have just read - A failed lambda sensor is actually one of the most common reasons for the ‘Check Engine' light.

Is there a way to test lambda sensor is defiantly faulty? Or should i go ahead and change it ?

Yes. Given that the EML is on there'll be a code you can read which will probably be a lambda error for bank 1. Also the sensor can be checked with a meter. Seems like a waste of effort though. I'd probably just re wire the sensor on the basis it's probably just cable damage and replace the hose. Clear the error codes and see if they re appear (might just need to disconnect battery for 15mins or using a code reader). If the lambda error re occurs then new sensor.

[bearman68]

spikeyhead said:

I'll guess that the cable has rubbed on the pipe, worn through the insulation on the cable and that has caused a short, which has drawn a lot of current and overheated the cable.

...or it could be something completely different.

^^^^^ This.

Lambda sensor has a decent size heater within it, shorting the supply wires could cause this damage I suppose.

[paintman]

What have the garage said?

[tomby]

paintman said:

What have the garage said?

There was a leak, the pipe has been replaced and the sensor seems to be ok.

Probably caused by what the others mentioned on here, rubbing wear/tear against the pipe and sensor, they have pulled sensor cable through more so its not as close to the new tubing.