Failing injector 1?

[tobi01]

Since a couple of days my car was facing rough idle and bad throttle response while engine is cold. I decided to change plugs to coder once and do a intake valve cleaning. During removal of plugs I noted that cylinder 1 plug was blackish and had fuel smell.
After cleaning and installation, car felt a little better. Today it started fine but after a couple of hundred meter the throttle response got real jerky and DME reported misfire on couple of cylinders. I cleared memory and now only cylinder 1 shows misfire and exhaust smells like fuel. I swapped coils between cylinder 1 and 2 but error persist. The AFR reading on bank 1 is quite high.

Would you think it is the injector 1 failing?

Thanks for your help

 

[tobi01]

Installed today a "new" injector but still cylinder 1 misfired. I removed the spark plug and look what I have found. Can not really understand what happened to i,t but just 100km ago it was fresh and gapped to .55mm. After installing one of the old plug, the engine started well and ran smoothly. My butt Dyno tells me it's not making full power but don't really know. I will make test drive and logging if weather is dry tomorrow.

 

[wheela]

OMFG!! Did you originality install that plug your self? Not sure how that would happen after install without physical contact

 

[tobi01]

Yes I did. And the car ran fine for 100km. Consequently the deformation must have happened while the engine was running.

 

[swellengear]

Thats not good.

 

[tobi01]

Unfortunately weather doesn't allow to make proper WOT logs but while cruising car feels fine. No smoke, no rough idle but subjective spool takes a bit longer.
I checked with a cheap borescope and definitely an impact on the piston notable but as far as I could see no scratches on the walls, residue or other noteworthy findings. Next week I will remove downpipes and check upstream the catalytic converter for debris.

 

[tobi01]

Checked CATs for debris, but nothing found. Car pulls fine without any timing correction, smoke or any other findings. Still wonder how this could happen.

 

[swellengear]

Weird! But glad thats its running well. Could it be possible that the plug was dropped before install, and you didn't notice the damage?

 

[SLOWESTN54]

That's some Audi levels of predetonation

 

[SlowE93]

That's some Audi levels of predetonation

 

[tobi01]

Weird! But glad thats its running well. Could it be possible that the plug was dropped before install, and you didn't notice the damage?

Nah it didn't fall and i handeld them like raw eggs. Additionally the car was running fine for 100km after plug installation.