Dead O2?

bowez

Registered User
Still dealing with my issue (funds been real tight). Now the A/F gauge (an autometer not wideband) is occasionally showing no signal. Today when I left work it blew out tons of black smoke (left spots in my parking spot). When the gauge is "working" after warm up it stays on the lean side, before warm up seems to run better.
 
Still dealing with my issue (funds been real tight). Now the A/F gauge (an autometer not wideband) is occasionally showing no signal. Today when I left work it blew out tons of black smoke (left spots in my parking spot). When the gauge is "working" after warm up it stays on the lean side, before warm up seems to run better.


I have two spare O2's if you need one to check. Both Bosch, one is a 3 wire the other a 4 wire. You can have either for the price of shipping.
 
sounds like a dead 02 my 02 start switching rich to lean after about 3 min . idle or cruising .mine goes in to open loop at 4 pounds of boost then 02 meter stays on the rich side around .7 to .8 volts i would check for dirty maf sensor too if its running lean or see if intercooler lines are loose . my big nut on top of sc worked loose but i think it made mine run rich
 
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Replace drivers O2 and it was covered in soot looked like was painted black. Idle and almost no throttle I get proper fluctuation of the gauge but at basically any noticeable throttle shows full rich.
 
Wondering could the crack in the my Double IC be causeing these problems? If I understand how the double is made I doubt it but.... Cause the plates on the sides of the double are just there to keep the the outside air flowing through the IC and not to keep the charged air in the IC right?
 
Last year when my lower intake manifold leaked coolant into both sides of the engine it ruined both O2 sensors. It ran pretty much like you described. The plugs fouled out black with soot from the excess gas. Since they were both coated and reading lean the eec pumped more gas in to try to make up for what it thought was a lean condition. My a/f meter would only light up 1 red bar. Try replacing the other O2 sensor as well. When my double intercooler developed a leak it ran only slightly lean lighting up 2-3 red bars and sometimes 1-2 yellow bars on the a/f meter.
 
Mike the lean issue is fixed now (last time pulled plugs only the drivers were fouled, but hoping since they are brand new 1month old they might clean). Cause I can get it to drive in proper switching mode (for the o2s) with just the right amount of throttle.

I will say yesterday after the new O2 it did dump a good bit of soot out the rear, ran Sea-Foam and no more soot... for now.

Mind seeing what Rick thinks? All this wouldn't be an issue but I still anit found a mechanic I know I can trust yet especially consider this thing.

Right now I'm thinking either fouled plugs (seeing right now if they will self clean, before I go order them, no no one out here has any of them in stock), IC crack (doubt it if my thinking of the double IC is right), other O2 (but last look passenger plugs were good, but no A/F on that sensor though), or MAP?, TPS?, IAC?
 
I connected my a/f meter to both O2 sensors and can switch between them and check both sides. On a cold start it takes the O2's about 2-3 minutes to come up to temp. I had my a/f meter ground connection go bad and it made the gauge read lean. It was 6 ohms off of ground. I rerouted the ground wire and "richened" it up considerably. How does it run otherwise? You may indeed have fouled plugs as well. Mine were so black I couldn't scrape it off so I replaced them all.
 
With the new O2 I installed yesterday the gauge is working just fine. Today the biggest issues seem to be more rev related than anything, off the line its just fine until about 2000RPM in drive, though in Neutral can rev it up; that being so I assuming its load related and makes me think plugs right?
 
I'd go ahead and pull the plugs in question and check them. When my collar nut came loose once it wouldn't pull any boost either but it misfired real bad when I tried to.
 
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