Help! Mr T say new O2 sensor/possibly new cat needed

[nafe]

I had the engine management light come on today so I rushed the car into Mr T to check it.

They have said that their readings indicate a faulty O2 sensor. They told me that if the light comes on again (which it did 20 mins later....) then I'll need to book the car in for a day to have the sensor replaced. They then went on to say that due to the extreme heat generated that it may shear off when they remove it and if so it will need a new cat !!!!   s:shock: :shock: s:shock:  

I've been told to expect about £250 for the O2 sensor replacement with the possibilty of over £1000 if the cat needs replacing.

If anyone could give me any advice on this I would be extremely grateful as I think I'm going to be having serious nightmares over this.... not to mention a major overdraft.  s:cry: :cry: s:cry:

[aaronjb]

Did they happen to tell you what error code you're getting?  With that we'd be able to give you a much better idea of what you're in for - so see if you can get that out of them.

You can get generic O2 sensors much more cheaply than that, but if they're talking about the CAT that makes me think it's the post-CAT O2 sensor code.. in which case:

a) It shouldn't be affecting performance (is it?)
b) It's probably the heater circuit - which can be bypassed (check a few threads down for info), and if it's the sensor itself then it can be replaced for £40 or so. Hell, the MrT sensor is £130 or so - so they're charging you a hell of a whack for fitting!

[nafe]

Thanks for replying aaron.
I just found some of the other threads regarding this matter, interesting reading !

MrT didn't give me the code but I'm going to contact them tomorrow and see if I can get this.
The performance definately doesn't seem to have been affected so I think you're probably right with your diagnosis. It wouldn't be too bad if it was just the cost of getting them to replace the sensor but I'm very worried about the issue of it shearing off and then having to replace the cat.

I read the thread about bypassing the heater circuit but I really don't think I have the experience needed to tackle that, sounds quite complicated.  s:? :? s:?  


I'll see what info I can get out of MrT tomorrow and I'll post again afterwards.

Many thanks for the advice.   s:) s:)

[nafe]

Well, I managed to speak to one of the MrT mechanics again today and he has confirmed that the the fault I have is with the sensor after the main cat. He even confirmed that the problem is with the heating element (as mentioned in other postings here)

I told him about my concerns with potentially having to replace the main cat if the sensor shears off as it's a ridiculous amount of money (over £1000) to fix a problem that's not really affecting the running of the car !
The only suggestion he had was to book it in with them, to replace the sensor, but if they can't remove it then ask them not to break it as I would rather take the car away with a faulty sensor than have to replace the main cat.
Apparently they try applying an oxyacetylene torch to heat up the area.  s:shock: :shock: s:shock:  


Does anyone have any other suggestions  s:?: :?: s:?:  

I've read about attaching a resistor to the sensor wires, but as I don't have any experience with this sort of thing, I'm not sure how easy a job this is. I'm not even sure if it can be done without removing the sensor !


Any help would be appreciated.

[spit]

Apparently they try applying an oxyacetylene torch to heat up the area.  s:shock: :shock: s:shock:

s:shock: :shock: s:shock:  They can be tough to get out, but with the appropriate tool and some easing oil (eg PlusGas), resorting to a torch really shouldn't be on MrT's list of possible solutions unless they've already completely naused up the removal! Don't let them do it.

Does anyone have any other suggestions  s:?: :?: s:?:  

I've read about attaching a resistor to the sensor wires, but as I don't have any experience with this sort of thing, I'm not sure how easy a job this is. I'm not even sure if it can be done without removing the sensor !

The resistor trick does work: it fools the ECU into thinking there is still a heater circuit there.

I lack any form of skill and can confirm that its a doddle. And yes, it could be done in situ, although a bit of crawling around is called for  s:wink: :wink: s:wink:  Ideally it should be soldered across the heater wires, but I had mine wired in with a common-or-garden terminal block for months and it was fine. Gets hot though.

Your next-cheapest alternative would be a generic O2 sensor, but this will need wiring onto the stock plug (and of course you'll have to get the old O2 out!), and an additional two wires to solder up.

Besides these are a spectrum of alternatives spanning from "ignore it" (not advised) right through to getting MrT to charge an arm and a leg for installing an overpriced sensor.

Being a notorious motoring-on-the-cheap git, I invested 20p in a resistor, but its your choice  s:wink: :wink: s:wink:  

If you're a little nervous about going it alone I'm sure someone here will be able to help out..... or pop along to Dyno day next Saturday - there'll be plenty of us, plenty of spare time and plenty of tools kicking about.

Ste

[nafe]

Thanks for the advice mate !

I was a bit shocked by MrT's idea of using a torch to heat it up, sounds a bit dodgy to me. I'm seriously tempted to get the tools and have a go at removing the sensor myself rather than letting MrT do it. I'm seriously worried that they could "accidently....." slip and break it off  s:roll: :roll: s:roll:  , giving me no other option than to replace the whole cat.

The resistor option definately seems to be the best in my situation (i.e. having no money...).
If not, I think I'll either get a non-toyota sensor to fit or even purchase a MrT one and just get someone else to fit it. As long as I can get the old one out of course.


Anyway, thanks again for the help.  s:) s:)

[Chris_h]

Being a notorious motoring-on-the-cheap git, I invested 20p in a resistor, but its your choice  s:wink: :wink: s:wink:  

Ah, I think we are from the same school of thought Ste   s:D s:D  

Have burned too much money in the past, if there is a cheap way - I wanna know!

I am actually having my car serviced next week   s:shock: :shock: s:shock:   - it goes totally against the grain, I don't normally keep them long enough. I still loathe handing over money to main dealers, so was sure to negotiate down to £79 - well, there was no way it was going to have the 4yr service...

Chris - tightass motorist


PS Nafe - its always nice when a potentially ££££ problem can be fixed for a few quid   s:) s:)