heat light on v6 petrol staying on.help!!

[hogggman]

Hi all,
following on from my battery problems today,i think i may have sorted that due to some dodgy connections.i took the bongo for a drive,and noticed the`heat`light on the dashboard was on.i pulled over,and then turned off/on the ignition,knowing that the light normally goes out after a few seconds.
this did not happen,but i drove slowly home,not knowing if i`d cause any damage by doing so.halfway home i noticed that the light had gone out.great,i thought,it`s cured itself.
not the case unfortunately,as it came back on again.
i did a quick search on here,and it may be related to the lambda sensor,but not sure.i do know though,that it hasn`t quite been running perfectly,especially when cold,and seem to`hunt`or chug a bit,but until today,have had no problems with the light coming on.
any ideas?
thanks
jamie

[cheffy34]

Hey hogmann mine has started that recently i'm still looking into it, it is to do with the sensor that sits in the cat pipe not the lambda which is pre cat mine started after i hit alot of flood water still runs but not sure it's 100% as far as i can make out it is only a pre heater for the cat pipe to give it a jump start i think, which means in theory it could be disconnected You can get the sensor from ebay £99, japtech the robbing gits want £174 daren't even try mazda mine is going on diagnostics tomorrow to see if he over/under fuelling etc some secondry sensors do pl;ay with the mixture but not this one i think and i stress think i will let you know what i turn up but the truuble with diagnostics is it could just go from one fault to the other and not really give a definative answer and not really get the fault you need, we see tomorrow


Dar

[hogggman]

i have my mot in february,so i hope it doesn`t mean anything bad for that.
thanks
jamie

[Nippon Tuck]

Just a thought and possibly a mile from being correct, but check all your fuses. Electrical work and water can do funny things to fuses. I recently installed a new stereo and must have done something in the process as when I finished the glowplug light kept flashing. I checked all the fuses one by one under the steering column and two were blown. I replaced them for about 20p and we all lived happily ever after.

[trevd01]

Catalytic converters and floods don't go well together:

http://www.rac.co.uk/web/car-insurance/ ... riving.htm

[scanner]

Catalytic converters and floods don't go well together:

http://www.rac.co.uk/web/car-insurance/ ... riving.htm

I like this rather sweeping bit of advice at the end of that.

If your car is damaged by flood, don't worry. Your car insurance will look after the repairs!

Not if it ain't Fully Comp it won't

[hogggman]

just cleaned and reconnected the plug for the lambda sensor and no light since.BUT i have seen the wire for the sensor to the cat,and it`s rusted away at the bit where it joins the cat itself,and there`s a rusty patch on the side of the cat where it looks like the wire joined.i`ve not noticed any detrimental effect though it has always been like it since i had the bongo in february.i don`t want to buy a new cat if i can help it.it did pass first time on the mot,though i`m sure the chap who took it warmed it up nicely first.if it`s a pre heater for the cat as supposed,will it be ok without it.is it more likely to be of use as in the colder parts of japan?
thanks
jamie

[cheffy34]

just cleaned and reconnected the plug for the lambda sensor and no light since.BUT i have seen the wire for the sensor to the cat,and it`s rusted away at the bit where it joins the cat itself,and there`s a rusty patch on the side of the cat where it looks like the wire joined.i`ve not noticed any detrimental effect though it has always been like it since i had the bongo in february.i don`t want to buy a new cat if i can help it.it did pass first time on the mot,though i`m sure the chap who took it warmed it up nicely first.if it`s a pre heater for the cat as supposed,will it be ok without it.is it more likely to be of use as in the colder parts of japan?
thanks
jamie

Ask the man that mot'd it

[dandywarhol]

I don't understand the "pre-heater" bit

If there's a sensor before and after the cat then one senses the oxygen content of the exhaust before it's converted and the one after the cat finds out how well its the cat's done its job. Sudden cooling of the cat by floodwater can crack the element inside and the sensor after the cat will tell the ECU somethings amiss which could bring the warning light on.

[cheffy34]

I don't understand the "pre-heater" bit

If there's a sensor before and after the cat then one senses the oxygen content of the exhaust before it's converted and the one after the cat finds out how well its the cat's done its job. Sudden cooling of the cat by floodwater can crack the element inside and the sensor after the cat will tell the ECU somethings amiss which could bring the warning light on.

It's not after the cat it's in the cat dandy known as a thermo sensor it all new to me, its not a secondry lambda i'm led to believe. It an import thing i think looking at cat pipes on the internet it only import ones that have the sensor smack bang in the middle of the cat pipe, And i understand what your saying cold quenching can crack the honeycombe or whatever it called, most common causes of cat failure are raw fuel being chucked down the exhaust and burning in the cat and causing meltdown usualy caused by a missfire or longterm running rich, (mine did missfire when i hit the water) cold quenching and something else i cant remember, i'm not so sure the sensor has anything to do with the mixture like the lambda does but i'm learning on it all the time, on mine it could be the sensor or the cat hence i'm not sure the diagnostics will pin point it, I'm not sure but i don't think the heat light on the dash is engine management, I don't suppose you have a manual to hand to check cheeky i know

Dar

[dandywarhol]

Only got a manual for a diesel cheffy

[cheffy34]

B*gg*r forgot about that small factor don't tell me it the future I suppose bad mixture would make the cat burn hotter which would trip the thermo sensor in the cat pipe knowing diagnostics i'll prob end up changing all 3 just aswell i'm onto a scrap pipe and sensor but hanging on for the diags, for-thinking i always look for the worst case senario it'll be a nice surprise if it a cheeeeeeeeeeeeeeeeeeeeeeeeeeeeep fix I've had one friend tell me it the lambda, the other tell me it just a kinda pre heat thingy disconnect it he says but both mechanics haven't thought of the worse case senario The CAT


Dar

[hogggman]

hi,
now i don`t know if the light was due to the lambda sensor or the wire that goes to the cat,as i cleaned the lambda sensor connections and it hasn`t come back on today.the wire to the cat had been dangling down touching,but not connected to,the cat,so maybe it was making a connection/short or something?that is now tidied up out of the way.
thanks
jamie

[manners]

What does the "heat light" look like? dont think ive got one on mine

[hogggman]

hi,
it`s on the right hand side,above(i think)the `roof `light,and should go out when you start up.
thanks
jamie