General Lambda sensor

[AY786]

Right, well i figured its about time i get this replaced to help sort my car out, basically ive located the lambda sensor on my punto - its where the exhaust manifold is on the right hand side (gold colour) and the wire leads on near the battery cover to where the clip is.

Anyone know how to replace this? What size spanner would i need you reckon? Also is there anything i need to be careful of or make sure i do (i.e. disconecting battery etc?). I rang a few local fiat garages to ask them how they go about replacing it and they said they un screw it, replace it and then reset the memory (how do i reset the memory) is it just disconnecting the battery for an hour or would i need to take it to a garage and falk out lots of money?

 

[MattMk1]

what Mk punto is it?

i'd spray a bit of wd40 on it then leave it for a bit to loosen it up. then a get a socket on it, just be careful not to damage it otherwise it won't come out at all.

 

[AY786]

its an mk2 1.2 16v, ok im nervous now lol

 

[marty61]

Yeah, take care undoing it its likely to be f ing tight. Watch you don't round it off and make sure the socket or spanner is a good fit

 

[canon]

When fitting the new one, if it doesn't go in smoothly - tap and rethread the hole or else it'll be a pig to get out next time round

 

[AY786]

wot about resetting the memory? shall i just disconnect the battery? Oh and will a 22mm spanner be fine?

 

[Most Easterly Pandas]

Memory shouldn't need resetting (I assume your having the injection lamp come on?), the injection lamp should just go out when changed.

To remove old one apply heat to the manifold where the Lambda thread goes into it with a blow torch, and it should come out really easily then, otherwise you'll be there all day

Jon.

 

[richie.guy]

wot about resetting the memory? shall i just disconnect the battery? Oh and will a 22mm spanner be fine?

22mm is correct.

Memory shouldn't need resetting (I assume your having the injection lamp come on?), the injection lamp should just go out when changed.

Not in my experience of Mk2 punto's - the code is stored and normally needs erased.

 

[AY786]

whats the best way to reset it then, just disconnecting the battery?

All i have is an 22mm spanner and a can of wd-40 lol

 

[richie.guy]

whats the best way to reset it then, just disconnecting the battery?

All i have is an 22mm spanner and a can of wd-40 lol

To reset an ecu, put the key in the ignition set to on but the car not started, disconnect both battery terminals and with a spanner if not enough slack touch them together, this will complete the circuit and remove all electrical energy within your cars ecu (the alternative is to disconnect and leave overnight...).

You then reconnect the battery. you start the car and do not touch the pedals while the engine get to optimum temperature (wait for the rad fan to come on the second time) you then switch off.

Switch on again and you can drive the car however keep the revs below 4,000rpm for the first 20 miles as you need lambda settings to map the higher rev range... after 20 miles the car is now reset and you can drive it as an italian car should be driven.

(If you thrash from the go, after 4,000rpm the ecu cannot read the emmissions so will go lean most likely)

Taken from www.puntomk2.co.uk

 

[AY786]

ahh thanks for that, but if i dont want to leave overnight as i need to drive the car straight away (if i can) switch the lambda sensor over, what do you touch together? Is it both the negative and positive terminals together? Is that safe?

 

[canon]

ahh thanks for that, but if i dont want to leave overnight as i need to drive the car straight away (if i can) switch the lambda sensor over, what do you touch together? Is it both the negative and positive terminals together? Is that safe?

I think he means when you disconnect the leads from the battery terminals you touch the leads together - wouldn't 'connect' the battery terminals, if you've ever dropped a spanner on them you'll know why! :slayer:

 

[AY786]

so just to clarify, when i disconnect the postive and negative leads i touched them together, would a spark occur or anything? And what was the spanner for or was it i connect the actual terminals on the battery together with the spanner?

 

[richie.guy]

so just to clarify, when i disconnect the postive and negative leads i touched them together, would a spark occur or anything? And what was the spanner for or was it i connect the actual terminals on the battery together with the spanner?

Remove both battery terminals.

Touch the terminals together to complete the circuit and remove all electrical energy.

Do NOT touch the terminals if they are connected to the battery in any way.

The spanner is incase the terminals arn't long enough to reach each other and touch, it acts as a bridge and conducts the energy.

As a caveat I didn't write the guide I quoted, my English is much better than that

 

[AY786]

has anyone ever tried this method before? Ive done some googling and some people say it can be bad for the electronics in the car?

 

[marty61]

Ive a feeling this is going to end in tears. PLEASE leave it to a professional. Talk about spanners and battery terminals is scaring me

 

[AY786]

UPDATE:
This morning, i got the part, bought the oxygen seonsor adapter, unscrewed the old one, came off quite easily, the new one was a pain to get in though, its not in 100% probably bout 90% but will that be ok?

Then i disconnected the battery touchted the two together with a spanner, dont know if it worked like but then when i started the car, the current millage since last filled up reseted, the mpg resetted, and the clock had resetted (doed that mean the ecu had resetted?), the idlling seems alot better now though, doesnt move up and down dramatically, accleration seems slightyl better though havent 100% tested yet as the first 20 miles i believe i have to drive under 4000rpm.

Can anyone confirm the ecu reset is a sucess or shall i disconnect the battery tonight and do the same procedure again tommorow?

 

[richie.guy]

Can anyone confirm the ecu reset is a sucess or shall i disconnect the battery tonight and do the same procedure again tommorow?

If you followed the procedure it will be done. Idle may be lumpy to begin with as it's re-calculating the mapping grids but it will soon settle down and run nicely.

Regarding the lambda - as long as it's not leaking it will be OK but I've yet to see one which doesn't screw all the way into the threads. Are you sure you haven't threaded it? Quite easy to do...

Ive a feeling this is going to end in tears. PLEASE leave it to a professional. Talk about spanners and battery terminals is scaring me

How will it end in tears? All you're doing is removing the electrical energy from the system which would normally take a few hours to discharge naturally. Stop being a woman

has anyone ever tried this method before? Ive done some googling and some people say it can be bad for the electronics in the car?

It's the correct procedure to re-set the ECU.

It's fine, I've done it plenty of times as have probably hundreds of people on puntomk2.

 

[AY786]

i may disconnect the battery though tonight and see what happens in the morning, just in case i may not have resetted it properly, i just drove it about 20 miles and in terms of acceleration, there wasnt much improvement from before to be honest, could it be something else then? e.g. map sensor maybe if my car has one?

 

[richie.guy]

What punto is it?
Why did you change the lambda?