Thread: Check engine light coming on, again..

ok i disabled the knock sensor by going to the ignition tables>Knock then unchecked the knock sensor, i did not uncheck knock analysis, i got the check engine light again on the way home and took a short log.. this time im actually getting a code, knock sensor..

heres the tcd/tlc

[ATTACH]763[/ATTACH]
[ATTACH]764[/ATTACH]

Since you're not running closed loop, disable the wide band sensor and see if that solves it. Be sure to clear DTC codes before testing. There may be another issue John and I will work on, but I believe the wide band O2 voltage is giving you the CEL.

Some things not related to CEL:
1) Are you running a 6 speed trans? If not, set "GEAR CALC MAX GEAR" to 5.
2) Your default IAT of 50F is causing a constant 2% IAT fuel trim. Unless this is what you want, set your default IAT (under SETUP, IAT SENSOR) to 70F so IAT fuel trim is 0 from the "IAT FUEL TRIM" table.

Dave

Hmm ok I will try that..

I'm not using my iat at all an last I checked it wasnted enabled? Should I still do that?

Even though you have no IAT sensor and an IAT sensor is not enabled, the IAT fuel trim is still applied based on the default IAT temp. you set. At 70F, IAT fuel trim is 0.

Dave

EDIT:
This is not quite correct. IAT fuel trim is applied ONLY when load source is MAP sensor. Since you are using MAF, it will not be applied, even though it is still set from the IAT FUEL TRIM table. You should still set the default IAT temperature to 70F. The ability to set a default IAT is for someone who does not have or want an IAT sensor, but still wants to be able to apply a fuel trim based on IAT, which they would set manually based on actual ambient temp.

did all these things you said, still getting the CEL, no codes tho, both knock boxes are unchecked, the senor and analysis.. i unchecked the wideband in setup but it still did it.. oddly enough, i think it only does it while the laptops connected... it didnt do it alllll day until the laptop was plugged in..

i made a recording if it helps but im sure its the same issue as the rest of the ones i've posted.

I believe the CEL is coming on because of high O2 sensor voltage. I've asked John to add the O2 sensor voltage limits to the wide band setup screen.

Dave

I am going to have this added later today along with a fix for the direct wideband issues.

I will post up when it is available.

well im still getting the check engine light.. i set the wideband dtc error thing to like max 5.10 and it still did it, so set the min to .01 but its still doing it..

things i've noticed that set it off:

light load low rpm's
having stuff on, like heater, defroster ect.
giving it a burst of throttle then letting off (decel in gear)

things that i've noticed make it go away:

another blip of the throttle
a long decel, say from 40 to 20

it did seem to do it less tonight, but i dont know, it doesnt seem to matter what afr it is really so maybe thats not it.. i've even disabled the wideband completely and it still does it. i've also disabled the knock sensor and its still disabled, both the sensor box and analysis boxes are unchecked.. could it be a battery voltage thing?

overall the cars been running great on SA, i've been using the closed loop with wideband and its great keeps me right where i want to be but i did dial the actual fuel table in just incase lol but this check engine light thing freaks me out haha

also, there are never any codes, not even when the light is on.

Your min maf voltage is 1v, try lower it to .9 or .85. It might be getting under 1v on that maf at light loads and such, causing the check engine light. Setup/Maf Load/Parameters, Min Maf Volts.

I was def hitting this on my z32 maf.... oh hang on, you are running map? Is maf still connected at all? Maybe check that value anyway, lowering it doesnt seem to hurt.

no no map yet, having troubles with that.. focusing on maf tune right now.. n60 maf.