Cylinder misfire

[Stu Lane]

Hi Guys,

I've searched but can't find anything with the exact problem I'm having.

Clio 172 cup 2002

Basically I've just put the engine back into my track day car after some general cleaning and replacing parts. I have another identical clio to swap parts for testing.
Engine runs and starts fine but there is a misfire and when i run the diagostics it comes up with a problem with the lambda sensor and a single cylinder. I know they don't idle well but it doesn't rev well either. Not badly but you can hear it.

Looking at the spark plugs, plug 2 is covered in carbon.

I tried swapping injectors, leads, plugs around (they are new), coil pack

I've unplugged the injector leads one at a time and I can hear it bog down so they appear to all be working

I've run a compression test and all is well.

I've replaced the lambda sensor (pre cat) although it has decat

the engine light is on but i've found before on track days it goes out sometimes and doesn't seem to make much difference.

I also noticed fuel in cylinder 2 and that's probably throwing the lambda sensor out.

I'm guessing if it's not a problem with plugs and leads then it's a wiring fault but I don't have a decent wiring diagram for the clio.

Any thoughts would be appreciated.

 

[bloke]

what did you read the codes with and what did they actually say?

 

[Stu Lane]

I read the codes with one of those bluetooth plugs and the Torque app.

While trying to ascertain whether i was getting a spark from all of the leads the immobiliser decided to get stuck on and wouldn't let me start the car. I swapped over the ECU, UCH and ignition barrel from the other car but it still won't start. I've checked all the fuses and swapped the relays over from the other car. I gave up last night and will have to have another look tonight.

Once I get it started, I can get the codes from the ECU again.