Cyl 4 spark plugs turn black
12-13-2016, 04:26 PM
#1
Cyl 4 spark plugs turn black
How come the f20c has a tendency to turn only The 4th cyl spark plug black what is different about cyl 4 some where saying it has to do with the breather being close to it is that true
12-13-2016, 04:34 PM
#2
Did you say black?! Oh crap man stop driving it now, everyone that I have seen where cyl 4 turned black the engine failed. Typically these cars were misshifted though, so as long as you didn't misshift you should be good.
12-13-2016, 05:26 PM
#3
12-14-2016, 03:35 AM
#5
That's how we feel when we read your posts. Black means too much fuel, if it's black and ashy it's oil. Likely a dribbling injector, the excess carbon deposits will create hot spots and raise your compression ratio, this is compounded by cylinder 4 having the most wall quenching as well as being the last cylinder to receive oil pressure.
12-14-2016, 04:12 AM
#6
Moderator
The F20C has no tendency to turn one plug black.
The problem lies in your engine alone.
You sure it was not loose? Is there black soot on the end of the coil pack?
Compression test will tell a lot here, if the loose plug doesn't pan out.
The problem lies in your engine alone.
You sure it was not loose? Is there black soot on the end of the coil pack?
Compression test will tell a lot here, if the loose plug doesn't pan out.
Last edited by Billman250; 12-14-2016 at 04:16 AM.
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12-14-2016, 11:28 PM
#9
That's how we feel when we read your posts. Black means too much fuel, if it's black and ashy it's oil. Likely a dribbling injector, the excess carbon deposits will create hot spots and raise your compression ratio, this is compounded by cylinder 4 having the most wall quenching as well as being the last cylinder to receive oil pressure.
how does one fix a dribbling injector
12-15-2016, 08:07 AM
#10
First I'd try cleaning it, there's many places that can do this, or do it yourself. An injector can be leaky if the pintle doesn't seat properly due to residue buildup.
To keep them clean you can use fuel injector snake oil treatment, I like the FP and LP stuff.
There's a crap ton of DIY's on youtube. Basically it involves flushing some cleaning fluid through the injector by removing them from the car and using a battery to activate them while rigging some way to force fluid under pressure.
To keep them clean you can use fuel injector snake oil treatment, I like the FP and LP stuff.
There's a crap ton of DIY's on youtube. Basically it involves flushing some cleaning fluid through the injector by removing them from the car and using a battery to activate them while rigging some way to force fluid under pressure.