micra 2003 1.2 cambelt chain renewal

i was wondering what i need to change for a cambelt chain change..
is it only the chance that is replaced or do i cahnge the rollers tensioners waterpump...


Club Member
i was wondering what i need to change for a cambelt chain change..
is it only the chance that is replaced or do i cahnge the rollers tensioners waterpump...
it,s an engine out job to change your chain, and the tensioners would need checking for wear :)
car has done 35k miles
am sure the chain has stretched as i can hear it i think..
so was wondering to get it done,,,,but at £500...i could have an engine replaced for that much...
do you get it seviced when it should if not oil will eat away at ur chain and strech it as it becomes acidic, check the tensioner if the pertrustion(how far the tensioner is out) is bigger than 10mm then needs new wher i work at main dealer in boston will cost about £1500 and its a full days work
regular oil services are done by myself, approx every 5k miles as the car doesnt do much mileage..so i do it yearly anyway.
i need to take a look at the tensioners to see how much out..
any advice on how i can do this
i recently had mine done at a nissan dealer
as this is the only place that can get the chain off
they changed a hell of alot of other parts with this
and the cost was £1182
the cover on the drivers side engine some 10mm blots but you gotta take the engine mount off to look, plus you need to take the plastic crap off thats on top or move it out of the way, and then the rocker cover

once the cover is removed then you will c the chain tensioner.

if you decide to do it then you will need to change then you will need to get a new chain, cam sprockets, crank sprokets, tensioners,

its a lot of work to do it really


Club Member
Sorry to bring an old one up but what mileage cycle is the cambelt change due on?

Thanks in advance
your engine light will come on long before the chain has stretched bad :)
(because of the cam sensor shift)
Cam Position Sensor - k12 2003

hi folks....
been pulling my hair out for weeks now... :(

baically ( depends how you look at it I suppose).

Engine light cam on - car stopped and wouldnt restart - after 5 mins it did..

Garage fault displayed p0340 !!! I think but was cam position sensor,

So the big question is where is this sensor so I can change it/test it.

I inherited the car from my lady indoors and as far as I can tell it has never been serviced.. It has 30000miles on the clock.

What would be the best approach at this stage etc ---

your help would be most appreciated(Y)(Y) considering there is a credit crunch on I dont want to hear a crunch from the Micra

Best wishes and thanks in anticipation for you help

cam sensor

thanks for your help and sugestion (Y) Frank .. So the plan should be remove the engine bracket on the drivers side - remove the gubbings from the cover and take a peek inside .. do you have or can you point me in the right direction of what I should be looking for ( pictures would be good)

again I thank you v much

ps incidently where is the cam position sensor anyway ??
If the Fault code is showing the cam position sensor will it mean 100% that the cam chain is stretched ?

I have so far removed the mounting bracket, top cover, connectors and lines etc, and now about to remove the rocker cover to inspect the "protrusion on the chain tensioner" the question is "Where will i find both the tensioner and the cam position sensor" ?

The original fault was - the car cut out at 50mph - no restart- engine light on. The car started after numerous attempts. but very underpower and fuel usage up .... Now car will not start at all but seems to have fuel -- so this is where I am at ( as above) Have sourced a replacement cam position sensor and hope to fit - when I can find out whre it fits :) this is where the experts come in HELP HELP HELP
oh dear

Thanks for the sketch at least I know where everyting fits. Do you have a picture of the location for the cam sensor -

thanks you very much
K12 03 1.0 Micra cam position sensor location

Hi all you experts out there --- Thanks for those who have contributed to my issues on this subject .... So here is the next set of oportunities.

Is the cam sensor on these on the top right of the cam shaft ? I have removed the rocker cover and can see the notched cam that sits in front of the sensor pick-up. I ordered a cam sensor from the local factors and it came as the wrong shape.:doh::doh::wasntme:

[COLOR="Lime"]So I sent the original back to the factors along with the new one. The chap at the supplier matched the numbers on the original sensor with those in the parts list and it comes up as the crankshaft sensor part - now I am really confused - I am gonna exchange this for the one that he has matched as I can only think that the cam sensor that I have removed is in fact the cam sensor as it is the only sensor that is actually on the top of the engine block and adjacent to the cam - Help would be very much appreciated [/COLOR]
Identfying the engine type

oK -- Cam position sensor replaced but still no change - car will not start -tries but not firing up - fuel smell but no go. looks like I have to change the chain - but how can I make sure it is the chain - theres a lot about check the protrusion on the tensioner ( more than 10m then u/s) I have had the rocker cover off, cleaned up the cam shaft but cannot see the tensioner to check it.

If I had to change to chain - although i know my car is a K12 how do I find the engine version/type - dont wanna buy the chain kit to find i got it wrong. on a scale of 1 to 10 realistically how difficult is the job.

thaks all looking forward to you responses



Club Member
i think all the CR chains are the same freddie (1.0, 1.2, 1.4)
and i think most garages will take the engine out to fit one (some threads on the ilexa forum)
checkout the haynes manual, it,ll give you some idea :)
I have replacd the cam sensor and cleand the end plate on the cam shaft but the car will still not start. it turns over and coughs and splutters tries to start ( did actually start once) but no chance. Whne i did start the revs only went to 2800, but after a few minutes were normal and the car ran ok. I ma puzzled here. A coup,e of questiions

When the sensors are replaced doe the error code need deleting for the changes to take effect

should the car not run albeit a bit rough if the sam sensor is faulty

and does the carnks sensor have an effect on the starting if that too is faulty.

and finally I have remove the rocker cover and looked at the chain but i cant see the tensioner protrusion does anyone have a picture or can they tell me wher to look. I am now an expert at removing the plastic bits tubes and rocker covers on a k12
help help help
when u look at the chain u will have the the two cam shafts at the top then as the chain comes down on the left hand side there should be a chain guide. on the guide u will see a a cylinder pushing on it that is the tensioner if the pistion is out any bigger than 10mm then the timing chain is streched and it will be an engine out job all day sorta thing
Thanks for the explanation I can do this now I know where to look.
Incidently would the car nort start at all if the chain ahd stretched?. I checked to reistance on the cam sensor plug pins and get readings I assume that I should get simular reading from the pins on the crank sensor ?? I did this had reading wer not comparible. When i now try to start the car it starts up but will not rev ( just runs roughly at 200 rpm then cuts out. could this be the crank sensor. Hopwever I
It puts the cam and crank sensors out of phase if the mil light was on it would say something about the cam or crank will sam more crank senser but it sound like a stretched chain
sound like the chain to me if it is over 10mm and it can be done with the engine in but it is very hard, i would advise doing it unless you know what you are doing one tooth out and it bent valves damaged head etc etc then it a goosed engine
sound like the chain to me if it is over 10mm and it can be done with the engine in but it is very hard, i would advise doing it unless you know what you are doing one tooth out and it bent valves damaged head etc etc then it a goosed engine

Thanks for the advice.. This stretched chain thing really winds me up. If i disconect the crank sensor I can get the car started although it takes a little persuation to bring the revs up, once running I reconnect the plug and away it goes. Runs like a bag of ***** though, under power, use more fuel. I managed to look at the cam chain adjustement actuator, but to be honest it is not that easy to look at even with a 500 watt light, the best way to view it is- First pust a clean rag into the chain drive compartment, this will clean off the oil that is coating everything and reflect back at the light. Now if you look from the front of the car into the chain areajust under the top rear pully about half way down you will see a round pin (about 12mm dia) that is pushing on the adjuster this I assume is the baby that needs to checked and it looks like mine is about 20-25mm extended from the body where it protrudes from -- so I now convinced that it is a stretched chain. so the next saga is how to change it and how many weekends will I have to work to earn enough money to pay for it - I have the K12 workshop manual on disk and it goes through the procedure, but not with the engine in situ - so if anyone can explain how I can do it without removing the engine etc I would be obliged and realisicaly how difficult can it be

best regards and thank for reading


Ex. Club Member
should take less than a day without taking the engine out! i've done loads and can do them in my sleep lol

dont even attempt to change it if you dont have a air compressor or you will knacker the variable pully on the inlet cam and it will never run right again