NJ_phil

Weird. Same ECM as me.

I think the gauge tries to read all supported PIDs after it boots up and won't display the ones the ECM doesn't respond to. My setup has 3 devices connected to the CAN, WB, HP tuners and the new OBD gauge and I have to disconnect the gauges to get HPT to work...maybe too much noise or crap on the CAN.

Not sure of your setup, but maybe you have a noisy CAN (LOL) causing bad responses when the gauge polls the ECM making those PIDs available. Possibly only attach the gauge if you're running other OBD stuff. I also enabled my flex fuel sensor but not sure if that has anything to do with it

EDIT: I believe the ethanol % on the HPT scanner is the same PID as the gauge (0x52) so the gauge should display it if the scanner shows it.

Unreal

Nothing else on port. HPT and any other device display those just fine.

I emailed AEM tech support. See if they can help.

schpenxel

Hopefully so--that sucks. I know they shipped a bunch of widebands with the wrong firmware on them when the -0333's came out. Maybe they screwed something up? Doubtful but who knows

Unreal

Would be interesting to see how it "polls" the ecu to see what is supported. I wonder if it reads model and just references a table of what that car should support, so added stuff that wasn't factory isn't supported.

NJ_phil

Good question.. We're running the same E38 so something has to be different. Maybe the OS rev?. They have to be some "secret" way of displaying the firmware version and I wonder if we have the same versions. Never wrote it down when seeing it on the label stuck to the back of the gauge and pulling that pillar apart to check the label is on top of my **** list, close to pulling the rack out.

Unreal

Honestly don't care that much, as ethanol percent isn't a big deal, just sucks that it says it does it, and it won't. Like I said boost can be done, just have to adjust my mind. Hit it this morning and saw 38psi on intake pressure, woot. Makes me feel great running mad boost.

schpenxel

How'd you figure out the address for alcohol %? The reason I ask is it appears it's different on E40's and I'm going to try to get dash logic to correct it so it'll display on dash logic. It works on E38's

Unreal

AEM instructions do like the PID number, probably pulled it from there.

schpenxel

Gotcha.

I was going to use commanded AFR to back into a rough ethanol %, but dash logic apparently doesn't have a PID for commanded AFR, only lambda.

I emailed them about it.. they told me my vehicle didn't have the sensor required to report commanded AFR. Palm face.

Unreal

I do have commanded AFR on this but it isn't accurate.

Shows 14.6, and then 11.7 when on it.

schpenxel

Gotcha, must be just multiplying lambda x 14.7 or something. Oh well, my dreams of showing ethanol on the DIC are crushed.

Unreal

Yah, it is, just lame that it does that.

FeArZ

So can you log your AFR or is it too much noise?
That would kind of suck to not be able to log while watching the gauge.

NJ_phil

I just unplug the OBD tap for the gauges when uploading and downloading tunes. The scanner works with the gauges, just messes up during tuning. I think download uses high speed block transfers on the CAN which is more sensitive than polling the scanner uses. No biggy

NJ_phil

That would be Wikipedia of course.

https://en.wikipedia.org/wiki/OBD-II_PIDs

Plus the fact that's the PID listed on the AEM website as Unreal mentioned. That PIDs an SAE standard, wonder why yours is different. As far as I know PIDS don't change from ECM to ECM and old ECMs have forward comparability to new PID requests by not sending a response if it's not supported.

schpenxel

Weird. Not sure if Dash logic did something weird/wrong on E40's or if GM just didn't follow the standard--It wouldn't be the first time

Technically no flex fuel vehicles left GM's factory using an E40 ECM, so maybe they didn't really care

NJ_phil

I checked their website for technical info on how that thing works but they didn't have much. Chances are they are polling 0x52 which the E40 doesn't support and the display just reads 0%.

That thing is pretty cool though. Didn't think GM had open access to the text display under the gauges.

schpenxel

Probably correct. HPT can log alcohol % on them fine on an E40 though so I'm assuming it's possible? You know more about CAN than me

NJ_phil

Something is weird...
HPT used the same PID 82 (decimal) for eth % which is 0x52 (hex) and the same PID as the OBD gauge so sounds like Dashlogic is messed up. Maybe give them a call and see what's going on. From what I saw on their website you can do firmware upgrades with "something", maybe a PC is it has USB

If you see it in the scanner, the E40 has to support it via 82d (52h)

schpenxel

Dash logic has tried to add stuff for me before (i.e. AEM 30-0333 CAN data) but it never worked right... I suspect it's possible if I could tell them exactly what I needed

Maybe HPT would be so kind as to tell me what address alcohol % is on an E40