Si Shane

I dont know very much about this stuff, so please just correct me if i'm wrong. Thanks

When i'm running in closed loop, the ecu runs off of the o2, right? If its open loop, then that is what i mean. But when my car is at idle, or partial throttle crusing it goes down very lean. EDIT: RICH!!!! it starts at 14ish (or lower, depending on my manifold pressure) and works down slowly by .2 incrimants to 11.0 to 10.5ish.

I have a 99si with a Greddy kit. Using the blue box. I also have a wideband installed, and it has a simulated narrowband output. When i installed the kit, i didn't have my primary o2 plugged in. I thoguht the simulated output would work fine. I threw a cel anyway, but the car ran very strong. And well.

I fixed it by plugging the sensor in, then wrapping in aluminum foil (just incase it heats up?). Ever since I fixed it, the car has been running very rich in closed loop. It didn't do this before, when i had the cel. It actually ran very well with the cel


Could this be caused by bunk simulated readings? I really dont konw. If you need any more info, just ask! Thanks


Modified by Si Shane at 10:38 PM 12/21/2004


Modified by Si Shane at 10:40 PM 12/21/2004

Si Shane

THis question is on the uberdata site too, but no response over there either. thanks for your help,. guys.

toolowsol

How lean is Very lean? What AF ratios are you getting in closed loop? I was going to try using my simulated narrowband output this week, so I'm also curious about peoples responses.

When you enabled the closed loop in uberdata, you didn't enable the o2 heater circuit did you? That will throw a code for sure.

Si Shane

it goes rich, i fixed the post.

eastbay92cx

I'm guessing the greddy blue box running extremely conservative. If not that then the stock ecu. Either way I don't think anything is wrong, you just need to get it tuned if you want it to run its best (try uberdata).

SOHC_MShue

how does it run if you take the wideband out and just run off the stock o2? Does it feel like its still running rich?

eddyboy

So your saying you have the O2 sensor pluged into the harness but you don't have the 02 in your downpipe but just have it hanging wrapped in tin foil...

Well I think thats your problem. If you are taking your simulated output from your wideband and splicing it into your ecu you need to remove the stock 02 sensor so it won't send your ECU data. The CEL you were getting was probably a 02 Heater Circuit. You need to fix that with a resistor. Or disable it in Uberdata.

GL

Si Shane

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eddyboy &raquo;</TD></TR><TR><TD CLASS="quote">So your saying you have the O2 sensor pluged into the harness but you don't have the 02 in your downpipe but just have it hanging wrapped in tin foil...

Well I think thats your problem. If you are taking your simulated output from your wideband and splicing it into your ecu you need to remove the stock 02 sensor so it won't send your ECU data. The CEL you were getting was probably a 02 Heater Circuit. You need to fix that with a resistor. Or disable it in Uberdata.

GL </TD></TR></TABLE>

We're on the same thought train. I had a cel when i had no o2. I was throwing a code bedcause of the circut, it wasn't complete. Even though the simulated output was there, the entire circut wasn't complete. So i plugged in the o2 then wrapped it in foil and secured it. I wrapped it in foil to prevent it from damaging anything.

I figured the actual measurement of the o2 sensor doesn't matter, since the signal cable from that unit was cut. Right you know the rest

The question is though, how would that affect my a/f ratio. When I had the cel, it was running much better, the a/f ratios were leaner and more proper for the closed loop cycle. Remember that a cel would normally add fuel, right?

I dont understand why it would run leaner and better in closed loop with a cel that pertains to the closed loop operation in the car, then after I fixed the cel. It runs way rich now

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">how does it run if you take the wideband out and just run off the stock o2? Does it feel like its still running rich?</TD></TR></TABLE>

I cannot tell, I need the wideband to determine a/f . I don't really want to drive the car without the wdieband. It has saved my motor allready