Whats this stuff on the spark plug? It is on the metal piece on the back an a bit on side
I had a misfire on this cylinder #4 an it may have been the plug wire connection ,seeing it smoothed out after replacing the wire an plug .
Is this from fuel additives?
An if the misfire continues should i look at injector ?
It kind of hesitates a bit at idle driving it an a tad less if i put it in park at a stop. I cleaned up the IAC an it was fine .The TPS is reading 13.5 also.
Any info is appreciated

 

Ash deposits. Burning just a bit of oil.

 

All the other plugs looked a bit cleaner.I replaced the 3 on that side.Other 3 still fairly new.An looked ok.
I tested the injector ohms an got 13.5.-Is that in range?
An I hooked up that pulsating light to injector plug an its working .I could feel it was working as running with a screwdriver also.
Was that ash deposit junk maybe why i was getting that misfire code?
An is it ok to leave newer plug wire on it for now ?
I will also be testing. a few cylinders for compression .What is the reading supposed to be ?
Thanks

 

If you change one plug, change them ALL. Also, make sure they are all gapped properly. Don't trust them right out of the box.

I think so....... Can't remember the exact value.

Fouled plug could indeed give you a misfire.

Change the rest of the plug wires too.

According to theory, anything over 100 PSI is "acceptable". Ideally, you want 150 or better, and all within about 20% of each other.

 

It did it again with misfire code.I made it over 70 miles before It did it again an a lot of city driving an start stops too.Slight hesitation ..seemed to hit after on interstate a while.


Here is a pic of rotor button an cap.Im fixing to replace them tommorrow ..Does it look like a factor?Yes its got the lines across the cap contacts.an button pretty dark.

Also it looks like a burn at center coil inside cap. Is that a factor?..rotor looks crappy too.
Any info is appreciated.

 

Definitely time for new ones.