Misfire

[Jack Maxwell]

Car has been running very lumpy the past few days and down on power. VVT doesn’t kick in until 5k. Engine light has blipped in once.

Ran an OB2 scam and got P0300 and P0313. Both misfire warnings

What is my best thing to try first.
Coilpack, spark plugs or lambda?

Cheers
Jack

 

[turkie172]

 

[Jack Maxwell]

View attachment 129796
View attachment 129797

Yeah that’s what I got on the reader. I also ran a voltage test on the O2 sesnor 1 bank 1 and got the following:





Not sure if these readings are normal or not

 

[Yiannis197]

Maybe is the cam sensor at fault here? It's pretty common.

 

[Foxspeed]

quickest/cheapest - check the plugs....sometimes you get water ingress in to no4/3 plug from the bonnet

 

[Jack Maxwell]

quickest/cheapest - check the plugs....sometimes you get water ingress in to no4/3 plug from the bonnet

Yeah I decided to check the plugs, found some water ingress into the drivers side plug. Replaced all four plugs and still got the same issue.

I've also removed and cleaned the cam sensor with no joy.

Think I'll try get a coil for the spark plug that was rusted/wet and see if thats at fault.

 

[Dumdum]

Yeah that’s what I got on the reader. I also ran a voltage test on the O2 sesnor 1 bank 1 and got the following:

View attachment 129798

View attachment 129799

Not sure if these readings are normal or not

Normally I’d expect to see the O2 sensor fluctuating between 0.1 and 0.9, the fact it’s reading 0v and flat lining for so long means something is up... might be a sensor reading incorrectly or another cause

Might be worth trying to check for any air leaks with a can of brake cleaner, spray it around the injector seals, inlet manifold gaskets, any joins in pipework, even away from the engine, the brake servo for example, any other seals/gaskets that have potential to leak air in other than where it’s meant to come from, any leaks will result in brake cleaner being sucked in and revs rising, lumpy running etc, you’ll know if you have a leak, if you wish to know what your listening for spray a little around the air intake (only needs a little to throw the mixture off)

 

[Dumdum]

I’d expect more like the red trace on idle

If I remember I will get my data logging stuff out on my diag and see what my 200 reads like

 

[Jack Maxwell]

Normally I’d expect to see the O2 sensor fluctuating between 0.1 and 0.9, the fact it’s reading 0v and flat lining for so long means something is up... might be a sensor reading incorrectly or another cause

Might be worth trying to check for any air leaks with a can of brake cleaner, spray it around the injector seals, inlet manifold gaskets, any joins in pipework, even away from the engine, the brake servo for example, any other seals/gaskets that have potential to leak air in other than where it’s meant to come from, any leaks will result in brake cleaner being sucked in and revs rising, lumpy running etc, you’ll know if you have a leak, if you wish to know what your listening for spray a little around the air intake (only needs a little to throw the mixture off)

Thanks, I'll try this out.

Do you think the O2 sensor could be causing this issue though?. Power is really down about 4K revs and lumpy too. Got the Misfire light (Flashing engine light) up a couple times.

 

[Dumdum]

Thanks, I'll try this out.

Do you think the O2 sensor could be causing this issue though?. Power is really down about 4K revs and lumpy too. Got the Misfire light (Flashing engine light) up a couple times.

It’s very possible that something else is causing the lambda to read wrong, unfortunately people (not you by the way ) seem to think that a code reader tells you what’s broken and what to swap, when in reality it gives clues

As I say a small air leak would perhap cause a similar fault, as would a miss programmed throttle body for example, and lots of other stuff I’ll stick mine on the Delhpi in a bit and see what mine looks like at idle

 

[Jack Maxwell]

It’s very possible that something else is causing the lambda to read wrong, unfortunately people (not you by the way ) seem to think that a code reader tells you what’s broken and what to swap, when in reality it gives clues

As I say a small air leak would perhap cause a similar fault, as would a miss programmed throttle body for example, and lots of other stuff I’ll stick mine on the Delhpi in a bit and see what mine looks like at idle

Yeah it's annoying. A few people have had this same issue and each one has been solved with a different solution. Going to try new coil packs today

 

[Foxspeed]

would have thought if it was a coil pack it would be a more constant mis-fire/issue

the slow to respond lambda readings are (if the reader is "accurrate") most likely a faulty/degraded lamba sensor but that again is a £80+ gamble

 

[turkie172]

The service manual has multiple tests to carry out regarding the two fault codes and also states the misfire can cause failure of the Catalytic converter system if allowed to continue if you even have them fitted and something stupid like the exhaust flexi joints blowing have been known to cause misfires. Unfortunately the service manual is 92Mb and cant be uploaded to the site and too big to email I would like to post the procedures but if Jack you cant carry out the tests that need a multi meter and the knowledge how to use it for example and checking certain wires from the injectors and coil packs connections to the ECU and the power switching units there's not much point of me doing so. The hole thing is based around the flywheel pickup sensor, fuel pump /relay, coils and injectors. If you have the capability and the equipment I'll go to the trouble of posting the procedures which is a lot of copying and pasting and probably a lot of wiring diagrams as well. If not a Renault specialist would be best as they may have seen this before and the knowledge of what is normal and what is not can go a long way to cut the repair time, also they would have possibly swap out parts for diagnostics to save buying unnecessary parts. I know it all sounds expensive but it's unlikely it's going to go away and I would hate to see more damage occurring if the car is going to drive with the fault daily. I've said it a few times the Renault clip does a lot more than generic code readers and was very quick to tell me that the second lambda on my 172 Clio was not heating and throwing the fuel readings out causing limp modes which I thought was water getting in as it happened when driving through standing water and driving with very little revs it had been doing my head in. Ok I've had a quick check you've changed coils and plugs that leaves the O2 sensors and the flywheel pickup I tried checking the resistance on the injectors and found one giving a different reading than the others so I changed them all and the problem with the flexi joints/ manifold is that it is a slow failure and just sounds normal it's not until they are fixed that you realise how quite it can be all I can say is look for soot on the pipework as some cracks are not visible when cold and open up when warm.

 

[mr angry]

Would it compress into a pdf document?

 

[turkie172]

It is a pdf document 92Mb 7991 pages covers all the Clio's X85 (Mk3) Nov 2009

 

[Jack Maxwell]

The service manual has multiple tests to carry out regarding the two fault codes and also states the misfire can cause failure of the Catalytic converter system if allowed to continue if you even have them fitted and something stupid like the exhaust flexi joints blowing have been known to cause misfires. Unfortunately the service manual is 92Mb and cant be uploaded to the site and too big to email I would like to post the procedures but if Jack you cant carry out the tests that need a multi meter and the knowledge how to use it for example and checking certain wires from the injectors and coil packs connections to the ECU and the power switching units there's not much point of me doing so. The hole thing is based around the flywheel pickup sensor, fuel pump /relay, coils and injectors. If you have the capability and the equipment I'll go to the trouble of posting the procedures which is a lot of copying and pasting and probably a lot of wiring diagrams as well. If not a Renault specialist would be best as they may have seen this before and the knowledge of what is normal and what is not can go a long way to cut the repair time, also they would have possibly swap out parts for diagnostics to save buying unnecessary parts. I know it all sounds expensive but it's unlikely it's going to go away and I would hate to see more damage occurring if the car is going to drive with the fault daily. I've said it a few times the Renault clip does a lot more than generic code readers and was very quick to tell me that the second lambda on my 172 Clio was not heating and throwing the fuel readings out causing limp modes which I thought was water getting in as it happened when driving through standing water and driving with very little revs it had been doing my head in. Ok I've had a quick check you've changed coils and plugs that leaves the O2 sensors and the flywheel pickup I tried checking the resistance on the injectors and found one giving a different reading than the others so I changed them all and the problem with the flexi joints/ manifold is that it is a slow failure and just sounds normal it's not until they are fixed that you realise how quite it can be all I can say is look for soot on the pipework as some cracks are not visible when cold and open up when warm.

thanks for the reply. I actually trained as an electrician and I'm time served, albeit I haven't sparkied in a few years. So basic resistance checks shouldn't be an issue.

What resistance would i be checking on the injectors? just the resistance of the coil?

 

[turkie172]

Right no problem the injectors have only two pins an are basically on or off so the Ohms between the two pins look for one that's different from the rest but on the 172 they are easier to get at not sure on the 197/200. So you have a multimeter then I'll have a go at uploading the test procedures I'll put them in the How Too section so at least paid members can look at in general it might help someone along the line.

 

[turkie172]

OK ERROR CODE P0300 Renault diagnostic code DF436 available documents
https://www.clio197.net/threads/troubleshoot-error-code-p0300-df436.61189/#post-709746

 

[Jack Maxwell]

Been doing some more thinking about this whole issue. I'm thinking the problem is that it is running too lean. When I removed each of the spark plugs they all were white, a sign of running too hot/too lean.

My thinking is too just go for the Lambda sensor, any thoughts?

Also which Lambda sensor should I change, upstream or downstream?

I cant imagine its a injector issue as all the plugs looked the same. Praying its not a fuel pump issue

 

[Dumdum]

Been doing some more thinking about this whole issue. I'm thinking the problem is that it is running too lean. When I removed each of the spark plugs they all were white, a sign of running too hot/too lean.

My thinking is too just go for the Lambda sensor, any thoughts?

Also which Lambda sensor should I change, upstream or downstream?

I cant imagine its a injector issue as all the plugs looked the same. Praying its not a fuel pump issue

Upstream influences mixture and is what your graph is from...

An air leak will also cause this... and costs 3 quid to find if it’s there!