K12 1.6 Sport SR misfire - I think I've tried everything!

A

Apretext

So, we have a misfire (usually comes up on the fault code reader as P0303 generic misfire on cylinder 3.)

Originally, I thought, coil or spark plug, so I replaced all the spark plugs, and the coil for cylinder 3. And, that seemed to fix it. For a week or two.

Then it came back. So I replaced ALL the remaining coils. Nope. Took it to a garage, and they spent hours trying to figure out what was wrong with it, replaced the crank sensor, and eventually said that when they plugged it into an oscilloscope on cylinder 3, after a bit it wouldn't pull to ground (and I googled, this is a common fault on that ECU). So, I found a company that fixes those ECU's, sent it off and.... No fault found. They had opened it up (as evidenced by the mangled screws and extra sealant everywhere), so they did look. So, I put it all back together today, hoping that maybe some pixies had magically fixed it, and after getting over the stupid immobiliser reset procedure, eventually got it started, and within a minute, it was back misfiring.

So, anyone any ideas? Getting more than a little bit fed up with it if I'm honest.... (Wife loves it, I currently very much don't.... :p )
 
Best to have the engine running at night and open up the bonnet to see if there is any arching of the HT leads, I would change the leads and use Iridium spark plugs as they tend to require less votage (putting less strain on the igntion system) for a superior spark and will last twice as long. also add a benzine additive into the fuel to clean out the whole system from the fuel pump to injectors as well as giving the engine a boost with the crap E10 fuel that is used at forcourts now!
 
Not a bad shout, although it's all under the bloody inlet manifold, so not sure I'm going to see all that much (honestly, who designed the manifold to be like that? Utter PITA...).

Are the leads available seperately? Already replaced spark plugs with shiny new iridium ones.
 
So presumably I need to get them to make a set for the 1.6, as that's not listed (I did look previously for HT leads when I first got this problem, but all the major suppliers just listed it as a cable reel....). I presume yours is the same engine? (your avatar looks very similair, only ours is a 5 door).

Edit: I've sent them a message, lets see fi they can do one.
 
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Have a word with the company they have over 30 years experience, and cross check your leads to make sure. My micra is a rare Sports diesel, but I have two petrol suzuki's that have suffered with age related problems similar to yours and the crap fuel they are supplying in the E10 petrol which caused stalling and starting problems, so now i run an additive every time I fill up.
 
Sadly, he can't help as it's coil on plug. We did try additives when it first started playing up, can't remember how much fuel we actually got through before the problem made it too bad to drive. The weird thing is it seems to be as the car begins to get warm that it happens, the first few seconds seem ok, then it misfires. I might try and clean up all the earths, maybe make a new earth cable direct to the ECU and one direct to the block and see if that cures it (my car ran MUCH better when I added in a bunch of extra big earth cables, and I have a few bits left over)
 
A compression check on the cyclinders, and check vacuum pipes etc, i know it must feel a pain, but going through a process of elimination is the only way to locate your problem. I spent months on mine last year sorting out corroded connections earth wiring and engine part replacements but I feel the k12's in good running order are a real jem when you look at the modern stuff that local garages are unable to even look at.
 
Mach1 said:
A compression check on the cyclinders, and check vacuum pipes etc, i know it must feel a pain, but going through a process of elimination is the only way to locate your problem. I spent months on mine last year sorting out corroded connections earth wiring and engine part replacements but I feel the k12's in good running order are a real jem when you look at the modern stuff that local garages are unable to even look at.
Click to expand...
We (or rather the garage), did find a vacuum leak in one of the gaskets, I believe they did a compression test (but can’t confirm). I don’t have a compression testing kit, and also the 1.6 has weird plugs which I had to buy a special tool to remove, so not sure if I was to go buy a compression tester if it would fit!

Edit: does give me a good excuse to buy some new tools though,…
 
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Apretext said:
So, we have a misfire (usually comes up on the fault code reader as P0303 generic misfire on cylinder 3.)

Originally, I thought, coil or spark plug, so I replaced all the spark plugs, and the coil for cylinder 3. And, that seemed to fix it. For a week or two.

Then it came back. So I replaced ALL the remaining coils. Nope. Took it to a garage, and they spent hours trying to figure out what was wrong with it, replaced the crank sensor, and eventually said that when they plugged it into an oscilloscope on cylinder 3, after a bit it wouldn't pull to ground (and I googled, this is a common fault on that ECU). So, I found a company that fixes those ECU's, sent it off and.... No fault found. They had opened it up (as evidenced by the mangled screws and extra sealant everywhere), so they did look. So, I put it all back together today, hoping that maybe some pixies had magically fixed it, and after getting over the stupid immobiliser reset procedure, eventually got it started, and within a minute, it was back misfiring.

So, anyone any ideas? Getting more than a little bit fed up with it if I'm honest.... (Wife loves it, I currently very much don't.... :p )
Click to expand...
What colour were the spark plug electrodes when you took them out. I had same thing with a punto years ago and it was head gasket just starting to leak tiny amount into cylinder. Sometimes it shows in exhaust gas when plugged up tp gas analyser. Took punto to tyre place that did mots and guy plugged it in for a drink. Worth a go👍
 
Spark plugs looked fairly normal from my recollection, but it was a while since I changed them, at the start of the issues. Might be worth getting a head gasket sniffer kit too then
 
We had misfire on corsa D while back, turned out it was the coil pack they are a single unit on these.
Due to standing it had corrosion inside the coils.
After swapping it ran well again.
Before that the engine sound like it was running on three plugs and as really rough.
I think these get water in them the vivaros do same thing.
 
I had a misfire and stalling issues on my suzuki and turned out to be oxygen sensor, this did not appear on any code faults and this sensor is linked to air/fuel delivery to the cylinders?
 
Interesting, I’ll see if it has one, it’s not something I’ve replaced. Edit: by oxygen sensor do you mean lambda or maf?
 
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I am not up to speed with the K12 micra petrols, however there should be a pre cat sensor and post cat (Lamda ) sensor. Pre cat sensor influences the fuel air mix content, and the post cat sensor monitors emissions, hope this explains it.
 
I think that a compression test is the way forward. If it always shows as cylinder 3, a burnt/leaking valve will show as a misfire.... (you do realise that the 1.6 L HR16DE engine is a Renault designed one and that some French engines have the cylinder numbering swapped so that cylinder one is closest to the flywheel? This threw us when swapping coils to try and cure a misfire on my daughter's 1.6 Peugeot, not sure if the Nissan/Renault engine is the same).
 
Had a similar fault on 1.4 micra. Tested everything I could myself. Fault code nonsensical? Saw a post on here that said when Nissan dealer gets same problem they change both oxygen sensors together as heaters are wired in parallel so fault code points to one fault where it is actually in the other sensor . Cured by swapping both out.
 
John_D said:
I think that a compression test is the way forward. If it always shows as cylinder 3, a burnt/leaking valve will show as a misfire.... (you do realise that the 1.6 L HR16DE engine is a Renault designed one and that some French engines have the cylinder numbering swapped so that cylinder one is closest to the flywheel? This threw us when swapping coils to try and cure a misfire on my daughter's 1.6 Peugeot, not sure if the Nissan/Renault engine is the same).
Click to expand...
the 1.6 is nissan engine as in nissan note 1.6
 
ray brewer said:
the 1.6 is nissan engine as in nissan note 1.6
Click to expand...
Still a Renault engine....
1696190201329.png
 
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