Engine Light comes on sometimes, doesnt matter if in boost

fox30 · Post by **fox30** » Mon May 17, 2004 11:04 am

hondata s200 with a p28 ECU / B18c1 / turbo / Apex AVC-R boost controller.

I dont think the boost controller is causing this but incase someone thinks so I listed it. Sometimes when driving the check engine light will come on either when I am slowing to a stop / acceleration or cruising. Doesn't matter how long the engines been running either.. Completely random. Pisses me off. I get no codes because when I switch the key off and back on / the light goes off / like its been reset. Anyone had this weird symptom before? Most of the time it doesn't light up.

Post by **Spunkster** » Tue May 18, 2004 1:26 pm

Check the code BEFORE turning off the car

shinociv · Post by **shinociv** » Tue May 18, 2004 5:08 pm

Are you running in closed or open loop O2 correction?

When i'm in open loop (no O2 correction) occasionally I will get a check CEL for the O2 sensor, but once I turn off the car it's gone with no record of being there.

fox30 · Post by **fox30** » Wed May 19, 2004 7:41 am

Well if you try to get codes before shutting the car off it wont blink to tell you the codes.. You have to have the jumper in then turn key on to get codes..

as for the other reply,
I am running in Open loop, and i just got my PLX Lambda hooked up and its displaying 10.5 - 11.5 mixture.. so It may be the engine light that comes on when at times its way rich maybe. so yeah maybe it was o2 related triggering from rich mix. I will adjust my tables a bit leaner and see what it does from there.
I'll post back when I get an answer.
Thanks for the tip
ps I thought the P72 was an ODBII? ( I saw it in your post sig line)

DaX · Post by **DaX** » Wed May 19, 2004 5:36 pm

Some P72's [as well as some P75's] are OBD-1 and some are OBD-2.

fox30 · Post by **fox30** » Thu May 20, 2004 9:06 am

Thanks DaX.

I forgot to mention, . I purposely left out the resistor on the wideband install because I am running in open loop and have (under RomEditor / options / Disable 02 Heater) is disabled in my map. Actually ALL error codes are disabled. So it should be ignored right?
Otherwise I still am stumped on why the light comes on.

shinociv · Post by **shinociv** » Thu May 20, 2004 12:29 pm

yeah, when you disable the O2 heater it ignores that error code. I have my O2 sensor wired so the heater is always on, I just switch between Wide or Narrow input at the ECU.

The reason I know that my error code is the O2 sensor is because often I?m datalogging and can check the code right away and I clear it at the next stop light when ever it shows up.

My O2 sensor CEL seems to just about always come on during a deceleration.

I don't know how the Hondata programing gets the ECU to not make O2 corrections but I think that has something to do with it.

DaX is correct about my P72, it's from a JDM 94-95 GSR OBD1

fox30 · Post by **fox30** » Tue Jun 08, 2004 7:39 am

nope, it still comes on.. less frequently though and my lambda is usually around 12 so I dont think its mixture related.. Too bad RomEditor doesnt show the error immediatly while datalogging. Like a popup window would be nice with an explanation of code etc.. I have no idea whats triggering this. As soon as I turn the key off and restart the light will stay off the rest of the day.

shinociv · Post by **shinociv** » Tue Jun 08, 2004 7:57 pm

I use ROMeditor to datalog too, when the CEL shows up I disconnect it save the datalog connect Hondalogger, look at what is triggering it, clear it and then disconnect and go back to ROMeditor to datalog.

I don't think I have ever had any other CEL show up. Also it doesn't matter if I have my Wideband O2 or Narrowband O2 pluged into my ECU. As long as I am in Open Loop it will show up occasionaly.

fox30 · Post by **fox30** » Mon Jun 14, 2004 12:01 pm

Thanks for the tip.. I'll try that.

ce · Post by ce » Mon Jul 26, 2004 8:43 am

I have the exact same problem.
My wideband O2 is defective so during startup it will show ridiculously high values. This means I can't use the narrowband output to connect to the ECU and run in closed loop (because it would just keep on adding fuel but never be able to get to the target voltage).
So I have to run in open loop for the time being..This is OK because all my table values are tuned..
But at random I get the O2 sensor A error and it pisses me off..I have disabled O2 heater (the wideband unit has it's own).

And when I get the error it's not running too lean or rich or anything..It's competely random..

Any plans to get this fixed ? Or have we seen the last update of the Romeditor ??

jpilcher · Post by **jpilcher** » Wed Aug 11, 2004 5:17 am

I am having the same problem. I have had this for the last year.
Only happens when I run in Open Loop. Lately it has been getting worse.
I recently installed a PlX wideband. I think it may have added to the problem. I have been running in Open Loop all the time. It's pissing me off as well.