Unusual mis-fire

[mark123]

My 182 has been developing a slight mis-fire for a while.
It only occurs (or is noticeable) at light throttle openings e.g. cruising at 30 in 3rd. Once you put your foot down a bit you cannot notice it e.g. 70 on motorway. But at idle when it is having a bad day it will put the flashing engine warning light on.
This seemed like injector faults I've had in the past so I swapped the fuel rail and injectors from the race car but it made no difference. So I swapped the plugs, lead and coil pack from the race car. While doing this I did a compression test that checked out all cylinders running similar compression. Changing the ignition components still didn't change the mis-fire.
I'm thinking about it being a wiring fault? I'll get my rs tuner on it while it is doing it and look at the sensor readings. I'll also try swapping some other bits, TB, sensors and TDC sensor from race car but non of them seem likely to me.

So I'm wondering if others have had similar and what the solutions were. Thanks.

 

[AlexW]

I'd pull injector plugs one by one, to prove what cylinder it is so you can hone in on that cylinder.

I can't think of any other things to suggest, as it sounds like a injector f**king up, but as you've changed that, highly unlikely. You've done everything I would have done by now.

 

[Chris_Beer]

Did you have any progress with this Mark? Mine has the same.. I've replaced the coilpack, ngk r plugs from Renault, leads. All new items. Cleaned the manky throttle body also. Its better but it still remains and is a pig in traffic

 

[mark123]

It was an injector in the end. Was just a dodgy one on the spare rail too!
If you pull the rail out and get someone to turn it over you can normally see which is the bad one from the spray pattern.
Keep a fire extinguisher to hand

 

[Chris_Beer]

Its been since my alternator went strangely, I got towed home on a tow bar in the rain so was very close to the car towing me. The engine was running for as long as the battery lasted and when I got home the engine bay was covered in dirty water, and I havent got a fuel guard cover and was unsure if it was possible water got down where the FPR sits on PH1 fuel rails and perhaps affected an injector. Ive never had it apart so unfamiliar if this sounds possible or not.

 

[Chris_Beer]

And forgot to mention a bosch pre cat lambda sensor too

 

[mark123]

Damp/corrosion in the injector plugs could cause it I suppose.
I'd pull the fuel rail and see if you can see which one from the spray pattern.