black soot - running rich - any ideas to help?

[Trevorc21]

So i have black soot all over the back of my car(alot!). I am sure it is gas because it wipes off and doesnt smear like oil does. And when i rip it i shoot black smoke at vtec. So i am running rich.
Replaced so far

PVC valve
Fuel filter
o2 sensor
fix header leaks
Fuel regulator
Temp gauge

also i rebuilt head so valves and guides where done.

Compression is ~215 across the board
Fuel pressure at rail is 43 at idle with regulator vac in and out is 54.



Any ideas what else i should do?

[BrandanVenne]

Stock computer? Changed Plugs recently? OEM distributor? New cap and rotor? MIL on? Oem exhaust?

[Trevorc21]

full exhuast i would expect alittle from that but 2 days after washing my car and 50 miles later it is like you spray painted the bumper.

Ya stock ecu but no mods that i feel would need a tune basically stock motor

Oem distributor have no idea when cap and rotor was done. Will def do that next

Plugs done like 10k ago

No cel

it idles at about 750-800 rpm and no hesitation. Drives very nicely.

[TypeRTeg669]

You don't have a wideband on the car do you? You sure the car wasn't previously tuned & at WOT/VTEC the map is real rich? I am interested to see what the solution is....

[Trevorc21]

No wideband. Running obd2 so i doubt he tuned it in any way. any real way to tell if it has been tuned?

[Craig92DA9]

I would pull up the datastream on a scan tool and look at fuel trims to see if the computer thinks its running rich or lean. If you have any exhaust leak allowing air into the system before the 1st 02 sensor the computer will richen the mixture when it doesent need to. Or you may find it is actually running rich. Also could be a bad catalytic converter, black suit is common on cars without one at all, perhaps its not functioning properly. Or your 02 could just be old and slowing down, not letting the computer have as tight of control over your fuel trim as it once was. hope something in there was helpful.

[justYncredible]

have you tried resetting the ecu? sounds odd but who knows

[Trevorc21]

Originally Posted by Craig92DA9

I would pull up the datastream on a scan tool and look at fuel trims to see if the computer thinks its running rich or lean. If you have any exhaust leak allowing air into the system before the 1st 02 sensor the computer will richen the mixture when it doesent need to. Or you may find it is actually running rich. Also could be a bad catalytic converter, black suit is common on cars without one at all, perhaps its not functioning properly. Or your 02 could just be old and slowing down, not letting the computer have as tight of control over your fuel trim as it once was. hope something in there was helpful.

Just did o2 sensor but ya i am going to scan it tomorrow, I will let you know.

Originally Posted by justYncredible

have you tried resetting the ecu? sounds odd but who knows

I have unpluggged the ecu harness and multi times take battery out. Shouldn't that have reset it?