p0340 code help

hi,
Apologies for asking for help on the first post, my other half has a 2003 k12 1.2 micra.

Symptoms as follows:
engine management light on
When cold idle is up and down and sometimes starts on the second or third try.
When warm it's much better but not perfect.

Upon scanning I get the code: p0340 Camshaft Position sensor problem bank 1 (snap on solus machine)
The camshaft sensor that was in the car was a non genuine one so after doing some reading online into timing chain issues I decided it wouldn't do much harm to fit a genuine item.

The problem I have is, I have booked it into my mechanics who has done a few k12 micras before for a new chain and he says he is not convinced the chain is the issue

The timing chain area has absolutely no noise and the engine is quiet.

I was just wondering if anybody had any other ideas and also information on how to check the chain .

Does anybody know what is on the other side of the camshaft sensor i.e what it measures against?

Any other things to check?

Thank you very much for your help
 

frank

Club Member
Has your mechanic measured the tensioner extension ? Because the crank and cam sensors go out of sync long before the chain gets slack enough to rattle
 
He didn't strip it that far but removed the rocker cover to check the cam lobes etc line up.

Also I rescanned the car with a eobd scanner and the fault code is the same but the description has changed.

It is now camshaft position sensor a bank 1 electrical fault in circuit
 
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Hi, I've done some further investigation today, when the car is cold the p0340 code comes up and if I clear it and rescan, it does the same.

However when I warm the car up to operating temperature fan kicks in etc if I clear the code it does not re-appear

I feel that something is getting warmed up by having the engine running. As when the engine is warm the car is running faultlessly

Can anybody tell me which pins on the ecu plugs the three wires from the cam sensor (green,red,black) go to?
 
Ok so I checked and the ecu and cam sensor wiring seem ok,

I went back to the drawing board and remembered that the mechanic didn't check the tensioner for the timing chain.

So I just whipped the engine cover and side cover off and attempted to measure the tensioner piston.

Roughly I think the piston is out 20mm

Would it be wise to ignore the eobd scanner and put a new chain in,

Bearing in mind the fault code only comes up when it's cold?
 

frank

Club Member
one member modded his cam sensor so that it was brought back into sync with the cam sensor, and got another 18 months out of the chain iirc
 

frank

Club Member
Any more info on this? All I'm really worried about is changing the chain and the fault still being present
i cant find the thread (there are hundreds of k12 chain threads eh ! ) i had suggested years ago that it was,nt actually a chain problem because 10mm extension on a tensioner with such a long chain is bugger all, and it was more a "sensor peramiter problem" but he said his mechanic shifted the cam sensor somehow
 
Just thought I'd update this, I had a new chain put in and it cured the problem.
Mines the 1.2 model and it was done with the engine in the car so it's not impossible
 
Ive just had the same fault code but the cars refusing to start,starting at ordering and replacing both sensors in hopes. Are the 2 sensors identical parts?
 
The 2 sensors look identical apart from an angled connector but I don't know if the are interchangeable. My car would start and then stall and I could get it to stay on by depressing the accelerator whilst starting.

Before wasting 80-90 pounds on new sensors (I'd advise genuine) id check the timing chain tensioner to,see how much it has come out - any more then 10mm and Nissan advise the chain as being stretched!

My own cars tensioner was at 20mm and it was fine when warm but a bit rough when cold
 
Cars had a bit of starting issue on and off for a while,before xmas mil came on and was cam sensor,but car was starting and running fine,just had the engine light. Sunday morn,car started fine,later in the avo it refused to start,had a check around,then nats kicked in car refused to even crank. Been towed to a garage today and the code p0340 came up. He cleared it and car still wouldnt start and code came up again. He disconnected the crank sensor and still kept reading cam sensor not even crank came up. Is all so confusing!!
 
Does the car crank now? Has the n.a.t.s fault been resolved? Am I right in saying you have already changed the camshaft sensor?

I suggest the next step you take is to inspect the timing chain tensioner, it's not really easy to get to as you have to remove the drivers headlight and engine mounting.

We bought a Lucas timing chain kit from euro car parts for around £100 - it took the mechanics a full day to do

So as these cars aren't worth much anymore I'd suggest you Inspect the chain tensioner and take it from there.

My mechanic was adamant that my chain wasn't stretched which put even more doubt into my head.
 
The nats is sorted,and the car cranks but refuses to fire up. Did have to replace the cam sensor last year,have ordered both sensors for now jus try the cheaper attempt at fix first lol Looking at chain kits in preparation for the worst though. Headlights ive removed more than i care to remember haha,ive done a fair few jobs on the car so not 100% novice at the car,just when it comes to electronic and ecu issues that stump me.
 
If your more then capable then I'd suggest stripping the air box, rocker cover, engine mount, headlight and side chain cover and having a peak at the tensioner. You will need a jack and block of wood to support the engine via the oil sump whilst the engine mount is off.

Whilst your at it inspect the camshaft where the cam sensor reads from for damage

My fear is that a stretched chain has put your timing so far out that the car will no longer start

My mechanic measured both old and new chains against each other and found it to be 2 links longer then the new one
 
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I replaced Cam and crank sensor yesterday,cars running a dream again,slight issue starting after almost a week sat idle an flooded from a fair few attempts at starting during that time. Once he started though,wouldnt have even known there was a problem :)
 
I have the same problem with my Micra K12 1.2 16V 48kw. it won`t start in cold but when it starts and get warmer is going without any problem. put`it on a tester the car has 2 error codes P0340 camshaft position sensor and another one which is Intake valve timing control solenoid valve. the last one i think it was gone because oil was present on both terminals. i`ve already replaces intake valve timing control solenoid valve and on tester it remains only one error code P0340 camshaft..... . Like you said before i`m not noticing any noise (loose chain noise). So you think if i change timing chain it will clear all problems? it is necessary to change chain, sprockets, tensioners.... or is enough to change the chain? is necessary to take out the engine?

Many thanks
 
I would start with replacing the cam pisition sensor before jumping to the big job of cam chain. I had cam and crank sensors go the same time and the car wouldn't start at all as its own damage defence if it was the chain. So personally i reckon your sensor is gone not a chain fault.

Sent from my C2105 using Tapatalk
 
I would start with replacing the cam pisition sensor before jumping to the big job of cam chain. I had cam and crank sensors go the same time and the car wouldn't start at all as its own damage defence if it was the chain. So personally i reckon your sensor is gone not a chain fault.

Sent from my C2105 using Tapatalk

Is necessary to replace crank sensor also? i changed intake solenoide valve, i will chande camshaft sensor with a SH one ( from a dead K12 micra) why i have to replace crank sensor? if i decide to replace chain is necessary to replace all kit or only chain?
 
I wouldn't bother changing crank sensor unless you have to,ad code is for cam sensor id just change that for time being. If chain is being changed,is just as well by the kit and replace the lot,engine has to come out to do it,so is a case of while its out,replace as many big jobs as possible.

Sent from my C2105 using Tapatalk
 
I wouldn't bother changing crank sensor unless you have to,ad code is for cam sensor id just change that for time being. If chain is being changed,is just as well by the kit and replace the lot,engine has to come out to do it,so is a case of while its out,replace as many big jobs as possible.

Sent from my C2105 using Tapatalk

i saw on forum that are people who replaced the chain with the engine in and are some with engine out. for sure is much easier with engine out but i think labour in hour is less with engine in.
 
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