permanent cel disable

[crispyduck]

any word on the p0420 dtc coming back crispyduck?

Crispyduck here. What I performed above is working great so far. If it doesn't come back in the next 24 hours then that will be conclusive - it works!

I intend reporting back then.

i worked out a table of addresses for dtc's on the A4SGD10C rom image. see attachment for table. the table contains 159 dtc's, and looks fairly comprehensive, but i'm wondering if there may be a few that aren't located in this memory space or coded differently.

it maybe easy to confirm the addresses using the accessport and comparing a rom image with and without specific dtc's disabled, one at a time. since cobb's method of disabling the dtc's works for sure, we would find out how they're doing it too. i ordered an openport 1.2 cable this past weekend, and as soon as i can read an image i will try a few different configurations using the cobb ap and editing the code directly.

edit: apparently i can't post attachments

Nice one for the table. If you send me a Private Message on here I'll send my email address and upload it for you if you want.

-Steve.

[diablerouge]

are the euro my03 wrx's equipped with the tumble generator valves? if so, maybe you can test disabling the same codes as khaos did and see if they come back. i read a post over on tari about the cobb ap frequently misreading codes numbered above p0999, so maybe khaos is disabling the correct dtc's, but the code which is throwing the cel is being misread. i will test the tgv codes when i can as well.

[crispyduck]

are the euro my03 wrx's equipped with the tumble generator valves? if so, maybe you can test disabling the same codes as khaos did and see if they come back. i read a post over on tari about the cobb ap frequently misreading codes numbered above p0999, so maybe khaos is disabling the correct dtc's, but the code which is throwing the cel is being misread. i will test the tgv codes when i can as well.

More than happy to help where I can. I've just read up on what the 'tumble generator valves' are from the Drive Subaru web site. Not sure how I would know I have them.

It's a Euro MY03 2.0 litre WRX turbo. It's not an STi so does not have the variable value timing (AVCS).

Anyone else know if my Impreza has these tumble valves?
-Steve.

[diablerouge]

i'm pretty sure all cars except the jdm's have tgv's, but you can tell if you have them just by looking. standing in front of the car, follow the intake runner on your right hand side down to the head. a car with tgv's will have an electrical connection to a small cylinder which houses the servo that controls the butterfly inside the runner. your injectors are mounted inboard of these risers.

[Kha0S]

are the euro my03 wrx's equipped with the tumble generator valves? if so, maybe you can test disabling the same codes as khaos did and see if they come back. i read a post over on tari about the cobb ap frequently misreading codes numbered above p0999, so maybe khaos is disabling the correct dtc's, but the code which is throwing the cel is being misread. i will test the tgv codes when i can as well.

Let me clarify --

The P1086 doesn't actually turn on the CEL lamp, but it does show up in a code scan. Perhaps the table there only controls which malfunctions will actually turn on the lamp.

/Andrew

[crazymikie]

Are you sure there aren't two tables- one for historic codes and one for current codes?

I know if I scan them with delta dash, there are two different columns in the CEL reader tool.


Mike

[Kha0S]

Are you sure there aren't two tables- one for historic codes and one for current codes?

I know if I scan them with delta dash, there are two different columns in the CEL reader tool.

Yeah... the 1086 comes up as a current code (I know the sensor is shot, haven't had a chance to replace it), but now doesn't throw the CEL or register a historic code.

[crispyduck]

i'm pretty sure all cars except the jdm's have tgv's, but you can tell if you have them just by looking.

Your right I do have them - in fact in my ecuExplorer diagnostics logs I get a voltage from the "Tumble Valve Position Sensor Left (V)".

[diablerouge]

while its good that it doesn't enable the cel, state emissions inspections here are done solely through the obd2 port. any current dtc will automatically fail the inspection. it would be better if we figured out how to disable the code entirely. i will be at home tomorrow, so i can take a diff of my cobb stage 2 rom with and without the dtc's disabled to see how they are doing it.

Yeah... the 1086 comes up as a current code (I know the sensor is shot, haven't had a chance to replace it), but now doesn't throw the CEL or register a historic code.

[crispyduck]

What I performed above is working great so far. If it doesn't come back in the next 24 hours then that will be conclusive - it works!
I intend reporting back then.

The CEL used to take up to 3 days of driving (that's around 210 miles) to illuminate from a fresh ECU reset - I have a decat downpipe and center. It's been just over seven days now since I set my P04020 code to 0x050000 and reflashed my ECU and the CEL has not returned - success

I've quickly written up a short technical article to document how to disable subaru fault codes. Feel free to have a look and correct/enhance as required.

A big thank you to Colby and the whole OpenECU community for providing the knowledge and tools to make this happen. Keep up the great work.

-Steve.

[Kha0S]

while its good that it doesn't enable the cel, state emissions inspections here are done solely through the obd2 port. any current dtc will automatically fail the inspection. it would be better if we figured out how to disable the code entirely. i will be at home tomorrow, so i can take a diff of my cobb stage 2 rom with and without the dtc's disabled to see how they are doing it.

Yeah... the 1086 comes up as a current code (I know the sensor is shot, haven't had a chance to replace it), but now doesn't throw the CEL or register a historic code.

I concur... same problem I'm trying to solve. My state is in the process of moving to OBD-2 emissions inspections... the shops know that there's no reason to fail for something like a TGV, but they're bound by the new system to reject for any current DTC.

Unfortunately, I don't have any other reflash capability aside from the stuff here, so I can't hunt down the way to disable it.

Keep me posted if you find out.

/Andrew

[diablerouge]

i have been under the misunderstanding that the cobb accessport would modify whichever rom you wanted to use to block arbitrary dtc's from appearing on a normal scan or triggering the cel, but this is not the case. although it clearly states in the manual that one of the features is the ability to suppress dtc's, it is not. they may have figured it out, but probably thought that they would have the dep on their doorstep if they allowed everyone to cheat state emissions. i'm going to request from cobb a rom modified to block just one dtc, in the off chance that they will give it up. if they do, we could have a few people request roms with different dtc's blocked, one at a time, and figure out how they go about it. in the meantime, i'll just stick to the 0x050000 method and hope it works.

any update on the p1086, khaos?

[cboles]

why is everyone so skeptical about the CEL fix I posted working??? has someone had it not work?

[Kha0S]

Works fine with everything but my P1086 code. I never said it didn't work for the others.

Even though the P1086 still shows in current codes, it doesn't actually throw the light or ever get put into historic codes... so it's even partially working for that.

[cboles]

gotcha - i missed that in my reading...