Misfiring and hesitation, check injection check esp warnings

[JackKTM]

My 200 has been a bit unwell recently, it's idling pretty rough but once you get the revs up it runs okay most of the time. However every so often I get a bad hesitation/misfire for a split second and then the car proceeds to run as normal again. When this happens I get check ignition and check esp warnings on dash but if I turn the ignition off and back on the warnings are gone and the car drive as normal until it happens again. Has happened when cold and when hot. I have tried moving the map sensor around while it's idling to see if anything happens but no luck. Spark plugs are only a few months old and it's had 2 coils replaced recently which hasn't made much difference. Only code I get on my basic reader is P0300 random cylinder misfire. I pulled the rail out today to have a look at the injectors all of them were clean on the tips and all 12ohms resistance. I've checked throttle body connector and was nice and clean but I have heard of throttle body's shitting themselves. Is there a way I can test the throttle body? Also does anyone know if both lambda sensors have the same connectors and can be swapped? I'm guessing if I swap them over and get a check emissions warning instead of a misfire then the upstream lamba might be faulty. Anything else I can check?

 

[Frank Perry]

I'd be looking at the spark/injection still - you said you have replaced 2 of the 4 coils which is a little odd, as normally when you replace coils you'd do all 4 at once so you have peace of mind knowing they're all good.

Check Cylinder 4 plug and coil/wiring (if you're looking towards the bay, it's the 1st on the left) as this is prone to water ingress due to leaking windscreen washer jets/pipes.

Pull the plugs out and physically check they are all good, for me, cylinder 4 always has the worst plug in it due to the above. I am yet to fix this, but since it's parked in my garage it's never really a problem.

Throttle body is easy to remove, there's a guide in the how-to section. Remove it, clean it, check it moves freely etc (being careful not to trap your fingers ofc!) and replace.

There's likely a lot more you could check but the above is what I'd start with mate. Fingers crossed you manage to find the issue and get it resolved!

 

[JackKTM]

There was two coils that were not renault parts and one of these two was causing a misfire so I just replaced the two so I had 4 genuine ones. I have a spare coil as well so I’m going to keep playing with them and swapping them out one by one.

I have personally had the washer jet tubing go on mine too about a year ago so replaced the tubing under the bonnet and haven’t had anymore leaks since.

I had the throttle body out today too and gave it a good clean, it wasn’t actually that dirty to be fair. I tried opening the butterfly valve but it was fairly stiff so I didn’t actually open it out of fear of damaging it somehow. Should it be nice and easy to open with your fingers then?

 

[burrellbloke]

The butterfly can be stiff but it should move when you push it with your fingers.

 

[Andy420]

There was two coils that were not renault parts and one of these two was causing a misfire so I just replaced the two so I had 4 genuine ones. I have a spare coil as well so I’m going to keep playing with them and swapping them out one by one.

I have personally had the washer jet tubing go on mine too about a year ago so replaced the tubing under the bonnet and haven’t had anymore leaks since.

I had the throttle body out today too and gave it a good clean, it wasn’t actually that dirty to be fair. I tried opening the butterfly valve but it was fairly stiff so I didn’t actually open it out of fear of damaging it somehow. Should it be nice and easy to open with your fingers then?

Hello mate, just joined the forums to see if anyone else has this issue. I'm also having this currently and have codes for computer internal electronic fault and misfiring detection. Car also wouldn't rev past about 2800rpm. Did you manage to find the fault please? Cheers, Andy

 

[JackKTM]

From what I can remember I replaced all 4 coils in the end for genuine Renault ones and didn't have any trouble from then on but I think the actual cause of the fault was a poor contact on one of the coil connectors. Pop them all of and have a look inside the female connector to see if one has a slightly bigger gap where the pins go in. Mine had one that was very slightly bigger than the others so I tightened it up a bit when I installed the new coils.