Well i have a plx m300 and i am running crome... i have the narrowband signal from the plx wired into pin d14 on my p28 nonetheless i still throw code 1 what gives? Did i forget something? i have o2 heater disabled but it is in closed loop. thanks for your time.

 

So when you jumped the service harness it was giving you a CEL 1? maybe you forgot to remove checksum or disable the knock sensor? Or maybe you burned the chip wrong? Also if you have the PLX setup to simulate a narrowband signal then you would want two O2 sensor options in Crome UNCHECKED. This is how you would use the PLX/NB setup to copy a stock O2 NB setup. If you have your PLX setup to wideband and you are going to be doing some AFR tuning you'll want to disable the two options for O2 senso. Thats "disable oxygen sensor (open loop)" and the other one "disable oxygen heater". You might not have to check disable heater, but if you do check it and you throw a CEL try unchecking it and see if the code goes away.

 

well i dont have the stock o2 sensor i busted it on a rock in the middle of the road one day


i'm not sure how to remove checksums?

the last one is UNchecked...

 

and if you wouldnt mind explaining the checksum thing i would be interested in learning.

 

From the menu go to PLUGINS then go to ENHANCEMENTS and hover over it to expand it. You'll see 4 sub-options pop up, the first one is Remove Checksum Routine. You wanna remove the checmsum before you save the .bin. Usually I open up my map and remove checksum before I start working on it. If you forget to remove the checksum it will gve you a CEL.

For the O2 stuff, if you are using a WB sensor but outputting a NB signal to D14 via the PLX controller then it's basically copying your stock setup. With this setup you'd want to have both oxygen sensors unchecked. Give all of those a try and see if your CEL goes away. Also pay attention to how you save the file...maye sure to name it MYBASEMAP.BIN and dont forget the .BIN at the end. And of course make sure you are burning the chip correctly and that it is not in backwards or on the wrong slots.

 

im going to try the checksum thing but if i uncheck the heater box i will definatly get a code because i dont have anything letting the ecu now i have successfully heated the o2 correct? i havent installed and resistors or anything because i was told you can just disable to heater which makes sense

 

I believe your WB sensor should be heated anyways through the wideband controller, since the WB sensor itself is not plugged into the stock harness which has the stock heater wires. Instead it is plugged to the controller, which I believe is where the WB O2 sensor heater signal comes from.

 

yeah but the ecu wants a signal from the stock 02 its A6 on ob1 ecus in the plx instructions it says to put a resistor on it or something to simulate the sensor being heated..make sense?

 

Just go ahead and disable the O2 sensor heater in the options. You shouldn't get any CELs regarding the O2 sensor heater because it has been disabled. I misread your other post and I thought that you said you were getting a CEL when you checked the O2 sensor disable. but I reread and see you were talking about a what-if situation.

Just go ahead and disable the O2 sensor heater and remove the checksum. Keep your fingers crossed and maybe you wont throw a CEL.

 

well the checksum didnt fix it..im all out of ideas. it comes on after like 10 minutes or so of driving its not like a normal bad o2 where it pops on right after you start it

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">yeah but the ecu wants a signal from the stock 02 its A6 on ob1 ecus in the plx instructions it says to put a resistor on it or something to simulate the sensor being heated..make sense?</TD></TR></TABLE>

No, PLX says to install a capacitor for noise filtration.

What you need to do is cut the stock O2 wire at the ECU. You can't have your ECU connected to the stock O2 sensor harness.

 

bingo.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EnzoSpeed &raquo;</TD></TR><TR><TD CLASS="quote">
What you need to do is cut the stock O2 wire at the ECU. You can't have your ECU connected to the stock O2 sensor harness.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EnzoSpeed &raquo;</TD></TR><TR><TD CLASS="quote">

No, PLX says to install a capacitor for noise filtration.

What you need to do is cut the stock O2 wire at the ECU. You can't have your ECU connected to the stock O2 sensor harness.</TD></TR></TABLE>

Are you talking about pin D14 is the wire he needs to cut? I read where he said he spliced in his wideband controller wire into the wire at D14. But if he doesn't have the stock O2 sensor installed or even hooked up I dont think it is necessary to cut the wire at O2 sensor wire. Then again I have an LM1 so I'm not 100% sure.

 

D14 IS disconnected from the harness it goes straight to the ecu. As for the capacitor could this be the problem? I wasnt sure how to install it and i was told i could just disable it so i didnt give it any thought

 

Disable all o2 check boxes, o2 feedback is not needed if you tune the vehicle properly.

 

i've been doing that i want to fix it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">D14 IS disconnected from the harness it goes straight to the ecu. </TD></TR></TABLE>

Well, maybe you need to cut the wire for the o2 heater as well? It's hard to trouble-shoot with a vx because they have those crazy 5-wire factory o2 sensors that nobody understands.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">
As for the capacitor could this be the problem? I wasnt sure how to install it and i was told i could just disable it so i didnt give it any thought</TD></TR></TABLE>

No, the capacitors clean up the power signal going to the PLX box so that your readings are more accurate. I never installed them on my PLX. Most people don't bother with it.

 

not sure what you mean by trouble shooting a VX i have an EX if you are talking about the car model...not sure if it makes a difference

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">not sure what you mean by trouble shooting a VX i have an EX if you are talking about the car model...not sure if it makes a difference</TD></TR></TABLE>

My bad, I started to confuse two separate threads I'm involved in


Did you download ECU Control? I would try to datalog with that and see if your ECU is getting signal from the wideband.

Also (this is a stupid question), did you make sure that your are feeding the narrowband (white wire) output into D14?

 

Also, what year is your car? On the 92-95's, the primary o2 sensor input is D14. But, if you have a 96-00, the primary o2 sensor input is D7.

 

its a 98 with conversion harness and p28 so i have it into the conversion harness straight into d14

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">its a 98 with conversion harness and p28 so i have it into the conversion harness straight into d14</TD></TR></TABLE>

Just make sure it's D14 on the ECU side of the harness. It's D7 from the other side.

This is actually a simple problem. Either you goofed the PLX input, or you goofed with the software. TRY TO DATALOG. That will tell you whether or not it's a software problem.

 

yeah ill have to come back when i have datalogged it i dont have a laptop yet so i cant right now..hopefully i can borrow someones soon...i know its installed correctlly however..