Running without O2 sensors
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Running without O2 sensors
Ok, quick question. What does the PCM do when it detects that both O2 sensors are gone?
The story is this, I just installed headers and have not got the cat-back system on yet. My headers don't have O2 fittings so I disconnected the O2 sensors all together for the time being. Running datamaster while driving the car around without O2s shows that the BLMs just sit at 128, which is good. Reviewing old datamaster with working O2 sensors show that the BLMs are generally at 128 or a little less. Under WOT however, they're always 128 with O2s. I figure it probably won't damage the engine, because if anything it's running a tad bit richer than it should be, and is exactly the same BLM at WOT as with the O2s installed. Anyway, I took the car out with my G-Tech to sort of guage a 1/4 time. Keep in mind that I'm at 3700 feet altitude. So far at the track my best time is 14.6 which works out to 13.9 at sea level. Anyway, with the G-tech I got 16.3 ?!? 1.7 seconds slower than normal, with open headers as opposed to stock exhaust!
So, I figure there are a few possibilities. 1. The G-tech is damaged. 2. The PCM is somehow slowing down the car to protect it from damage. 3. A wire is not connected, burnt or something of the like. 4. I didn't reconnect a wire when I put everything back in.
Anyone have any theories? I did do a run with datamaster and found that very little spark retard was present and although it did detect a few false knocks, it was not many and not enough to slow the car down that much. At most during the WOT run I got 1.5 - 5 degrees of retard and most of the time it was 0.
The first thing I'm going to do is check for all the connectors, then I'm going to install the taylor OTVC wires I bought and then lastly I'm just going to wait for the rest of my exhaust system to arrive in the mail.
The story is this, I just installed headers and have not got the cat-back system on yet. My headers don't have O2 fittings so I disconnected the O2 sensors all together for the time being. Running datamaster while driving the car around without O2s shows that the BLMs just sit at 128, which is good. Reviewing old datamaster with working O2 sensors show that the BLMs are generally at 128 or a little less. Under WOT however, they're always 128 with O2s. I figure it probably won't damage the engine, because if anything it's running a tad bit richer than it should be, and is exactly the same BLM at WOT as with the O2s installed. Anyway, I took the car out with my G-Tech to sort of guage a 1/4 time. Keep in mind that I'm at 3700 feet altitude. So far at the track my best time is 14.6 which works out to 13.9 at sea level. Anyway, with the G-tech I got 16.3 ?!? 1.7 seconds slower than normal, with open headers as opposed to stock exhaust!
So, I figure there are a few possibilities. 1. The G-tech is damaged. 2. The PCM is somehow slowing down the car to protect it from damage. 3. A wire is not connected, burnt or something of the like. 4. I didn't reconnect a wire when I put everything back in.
Anyone have any theories? I did do a run with datamaster and found that very little spark retard was present and although it did detect a few false knocks, it was not many and not enough to slow the car down that much. At most during the WOT run I got 1.5 - 5 degrees of retard and most of the time it was 0.
The first thing I'm going to do is check for all the connectors, then I'm going to install the taylor OTVC wires I bought and then lastly I'm just going to wait for the rest of my exhaust system to arrive in the mail.
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