high 0'2s????
- Thread starter cold85
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Me too dude,
I have 900 + and just when I think Knok is 0 it shoots to 5. I could turn my fp to 20 and still have have high 02. I took my secondary fp offline and ran on the stock wired primary fp. Still have high 02s! A pit bull chip does this and so does my ramcharger-no diff whatsoever! My fp gauge agrees with my tool box diagnostic gauge. I am clueless. Maybe a Testa chip would be answer.
I have 900 + and just when I think Knok is 0 it shoots to 5. I could turn my fp to 20 and still have have high 02. I took my secondary fp offline and ran on the stock wired primary fp. Still have high 02s! A pit bull chip does this and so does my ramcharger-no diff whatsoever! My fp gauge agrees with my tool box diagnostic gauge. I am clueless. Maybe a Testa chip would be answer.
blackbuick87
Senior Member
- Joined
- Mar 11, 2002
- Messages
- 3,205
High O2 readings usually mean a fouled sensor
Also O2's as high as 900 are probably causing "rich knock"
Look at the crosscounts on your SM. It should climb to 255 VERY quickly (less than 10 seconds) and recyle to zero and start all over again. If they are climbing slowly the sensor is shot
Also O2's as high as 900 are probably causing "rich knock"
Look at the crosscounts on your SM. It should climb to 255 VERY quickly (less than 10 seconds) and recyle to zero and start all over again. If they are climbing slowly the sensor is shot
Thanks for thoughts guys,
I ran leaded race gas one time at track-is that all it takes to foul a sensor? It is only 6 months old and a Delco. I am aware of rich knock. What are the physics of it-why does a rich mix knock? The only exshaust leak possible is at 3 prong base of turbo. I dont run a gasket there, but i dont hear any leaking either.
Will try checking o2 c.counts and then a diff sensor-thanks.
I ran leaded race gas one time at track-is that all it takes to foul a sensor? It is only 6 months old and a Delco. I am aware of rich knock. What are the physics of it-why does a rich mix knock? The only exshaust leak possible is at 3 prong base of turbo. I dont run a gasket there, but i dont hear any leaking either.
Will try checking o2 c.counts and then a diff sensor-thanks.
My brand new Delco 02 sensor started coding on my two days after running only 8 gallons of 114 through it. Some are more sensitive than others.
I would recommend putting a gasket and some copper RTV sealant between the turbo and header connection. You're probably getting an exhaust leak there. Try to "feel" exhaust at that location with the car running.
I would recommend putting a gasket and some copper RTV sealant between the turbo and header connection. You're probably getting an exhaust leak there. Try to "feel" exhaust at that location with the car running.
Thanks Tom87,
I did find some carbon (from leak) between d.side crossover pipe and header and found that bolt turned 2 times when tightened. Checked all other points incl. turbo base. Changed o2 sensor . Took a ride. Of Course-high o2s and now an extra little surprise: Lower boost! Kinda reminds me of when my buddy would drop by in his 71 LeMans-I would set his point dwell because it would be way off , he would drive car and be dissapointed and get me to set dwell back to improper setting! Heck, last week I found a ruptured throt body gasket. It would suck in oil as fast as you could squirt it. Did it help car run better at all to put in a new gasket? Hellnaw. Still have tip in stumble , high o2 at wot, low o2 at snap shut trottle, inconsistant max boost. And yes I cannot find another vac leak. Yes tps is new and correct, iac,throttle blade is clean. FP can be set LOW and still , high 02. Im running atr bleeder style boost control. It has always given low boost on takeoff and creeps up by 2psi by top of second gear which always results in a Knock at 3rd gear change.
Later, TIA
I did find some carbon (from leak) between d.side crossover pipe and header and found that bolt turned 2 times when tightened. Checked all other points incl. turbo base. Changed o2 sensor . Took a ride. Of Course-high o2s and now an extra little surprise: Lower boost! Kinda reminds me of when my buddy would drop by in his 71 LeMans-I would set his point dwell because it would be way off , he would drive car and be dissapointed and get me to set dwell back to improper setting! Heck, last week I found a ruptured throt body gasket. It would suck in oil as fast as you could squirt it. Did it help car run better at all to put in a new gasket? Hellnaw. Still have tip in stumble , high o2 at wot, low o2 at snap shut trottle, inconsistant max boost. And yes I cannot find another vac leak. Yes tps is new and correct, iac,throttle blade is clean. FP can be set LOW and still , high 02. Im running atr bleeder style boost control. It has always given low boost on takeoff and creeps up by 2psi by top of second gear which always results in a Knock at 3rd gear change.
Later, TIA
Where are you getting your readings? Track or street. Keep in mind that when you hear people talking about tuning for the upper mid-700s, they are talking about a value at the end of a 1/4 mile run. The reading will start significantly higher and then fall off through third gear as you finish a run. So you're not likely to get a useful reading on the street unless you have a lot of road to keep your foot in it. Doesn't sound like that's the answer to your problem, but it is something to keep in mind as you try to sort it out. 
Good luck.
Good luck.Thanks Dean,
Im getting info from an Auto Xray 240 on street runs. Sometimes from a 20mph kik to top of 3rd and sometimes 50mph kik to about 95. What seem s really odd is that dramatic changes in fp dont give any diff o2s. May be 980 down to 920 but always 9's.
I have ATR double scumpers. Maybe I have a bad fp reg and it can't handle the fuel when the second pump stages on.?
TIA
Im getting info from an Auto Xray 240 on street runs. Sometimes from a 20mph kik to top of 3rd and sometimes 50mph kik to about 95. What seem s really odd is that dramatic changes in fp dont give any diff o2s. May be 980 down to 920 but always 9's.
I have ATR double scumpers. Maybe I have a bad fp reg and it can't handle the fuel when the second pump stages on.?
TIA
