SidewayzSkyvia Posted March 2 Report Share Posted March 2 Hey I'm using a wrx11x to run an rb25 in my Subaru Impreza. Everything seems to be working fine. But the car won't rev over 3k/3500ish. It cuts out completely, drops a few hundred rpms. Then it will start revving again. I've changed the rev limit around. I've even disabled it. Doesn't seem to change anything. Am I missing something? Or could it possibly be a fault with the cas? Oh and another question, is it possible to use an aem 30-0344 OBD2 wideband gauge over can bus with this ecu? I've also attached a copy of my tune and a couple logs. Thanks. wrxR2 low rev limit.pclx rev limit.llgx TriggerScopeLog.llgx Quote Link to comment Share on other sites More sharing options...
essb00 Posted March 2 Report Share Posted March 2 Other than the overrun fuel cut, there was no other limiter activated on that log. However, there is no lambda recorded on the log (you have selected Link CAN on Lambda 1, but it seems your AEM UEGO is not sending lambda readings to CAN), so it cannot be told if it was lean or rich before/after the actual 'misfire'. Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 2 Author Report Share Posted March 2 Yea Im thinking the 30-0344 isn't outputting to the ecu properly. I have the can stream side set up following the help file. But it looks like the gauge itself has different outputs than the regular x series because it's the OBD2 variant. It's also not so much a misfire, it seems like a soft limiter. It runs good and revs good under this limiter(considering it isn't tuned yet) The wideband gauge also showed 10/11 afrs when it happens. Free revving the engine it will just cut out until the rpms drop a lot then it seems like the ecu turns everything back on. Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 2 Report Share Posted March 2 I would start by fixing the fuel settings first. Or better still, turn off multi-fuel and tune the unblended primary fuel first. Multifuel density is set to 99% eth value but the stoich ratio is set to a gasoline value. Lambda target 2 is set to 0.4 Turn off the 4D fuel table. Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 3 Author Report Share Posted March 3 Im guessing I messed up the dusp table stuff when I copied my tune over from my old g4+. I'll get that sorted. I'm thinking it's a cam angle sensor issue though. As I took it apart to inspect it. Bearings are very crunchy. I sprayed it out with electronics cleaner and it revved up to almost 6k a few times. Then it started going back down to 3-3500. I'm gonna try to source another one or change to a different trigger setup to verify. Quote Link to comment Share on other sites More sharing options...
essb00 Posted March 3 Report Share Posted March 3 AEM 30-0334 only outputs OBD-II PIDs, not like the 30-0300 which is connecting via AEMNet (actually, they seem to be the same device, just different firmware). Your best bet to make that work is to connect it using the 0-5V analog output and connect it to an unused analog input of your Link ECU. ....at 72% ethanol, the approximate stoich is about 10.6:1, so seeing 11:1 on your AEM gauge proves it is leaning out. You've got to fix the items pointed out by AdamW. Quote Link to comment Share on other sites More sharing options...
koracing Posted March 4 Report Share Posted March 4 23 hours ago, essb00 said: ....at 72% ethanol, the approximate stoich is about 10.6:1, so seeing 11:1 on your AEM gauge proves it is leaning out. You've got to fix the items pointed out by AdamW. That would depend on if the gauge is using the ethanol scale. The instructions show it can display Lambda, or 14.7 gasoline scale, or O2 %. I assume he is on gasoline scale, so it would indicate it being extra rich. https://documents.aemelectronics.com/techlibrary_30-0334-x-series-obdii-wideband-uego-controller-gauge.pdf It looks like it does output to a few options of hex address on the can bus - so there may be the ability to read it over CAN to the Link if a custom user stream was set up. Default output address is: 6 (default) 0x7E6 (for 11 bits) 0x18DA28F1 (for 29 bit) with the default being 11 bits output and 500kbps output. @Adamw Is this possible to recieve under a custom user stream? Quote Link to comment Share on other sites More sharing options...
koracing Posted March 4 Report Share Posted March 4 Would this be CAN Mode: User Defined -> Bit Rate: 500kbps; Data: Mode: Receive User Stream X-> CAN ID 2022 --> Format Normal? Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 4 Report Share Posted March 4 No this is an OBD2 protocol device only as far as I know. OBD2 is a request/response type communication, there isn't data continuously broadcast. So for example to get lambda from this device, the "Scan tool" needs to first request it, in human language it would look something like this: "hello, Im a scan tool, ECU #6, please send me the current 02 data for sensor #2", the gauge then responds with just a single data point for that specific request and includes confirmation of what device it came from and what it represented. If you want a continuous stream of data you have to keep requesting it again and again - and you cant make a request until the previous data has been received. You could probably make it work with user streams by sending out a constant request, but the nature of this protocol is slow, probably less than ~10Hz at a guess so you would be better to use the analog output for connection to an ECU. The intent of the gauge is to be convenient to log alongside ecu data with an OBD2 based logger like HP tuners etc, it is not designed to send data to an ecu this way. koracing and TTP 2 Quote Link to comment Share on other sites More sharing options...
dx4picco Posted March 6 Report Share Posted March 6 On 3/4/2024 at 7:24 PM, koracing said: @Adamw Is this possible to recieve under a custom user stream? on the 0300 https://documents.aemelectronics.com/techlibrary_30-0300_x-series_wideband_uego_afr_sensor_gauge.pdf I've been able to receive sensor fault and data valid in a custom stream if I remember right. but on the 0334 aemNet doesn't seem to be the same Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 6 Author Report Share Posted March 6 I ordered an aem 0300 kit. So I'll be able to log lambda here soon. And I've located a different cam angle sensor to try out. I'm still leaning towards it being a cas issue as when the engine isn't up to temp it will usually rev a bit higher, up to around 5k. When it gets up to temp it won't go over 3k or so. I've also made the changes Adam suggested to the tune. Once the new wideband gets in I'll try it with those changes. If it's the same thing I'll put a different cas in and hope for the best. dx4picco 1 Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 9 Author Report Share Posted March 9 Still waiting on new wideband to show up. But I changed the settings in the tune. Got the engine running again. It's a little rich at idle but it's running. Still not reving though. I was looking at things and it looks like the injectors are still being commanded on when the "limit" happens. Old wideband is showing full lean spikes when limit happens. Fuel pressure is holding steady around 44-46psi when limit happens. Verified timing again with timing light. It's spot on. I don't seem to be getting many trigger errors to support my theory of a bad cas. And I'm suspecting it's losing spark though. It also pops sometimes when it starts reving again, like it's continuing to get fuel and loses spark. I will update again when new wideband and cam sensor shows up. Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 15 Author Report Share Posted March 15 Adjusted the tune. Put in a new cam sensor nsame result. Did some more digging. It looks like the non turbo Impreza chassis I have has a different fuel pump control module than a wrx/sti. So the base map 3 speed pwm strategy was actually turning turning off the fuel pump at 3k rpms. Set it to standard and it now revs up just fine. Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 16 Author Report Share Posted March 16 Tinkered with it some more. It's still not working properly in standard mode like I thought. I'm theory I should just be able to bypass the fuel pump control module and just use the fuel pump output to trigger a relay for the fuel pump right? yncz 1 Quote Link to comment Share on other sites More sharing options...
koracing Posted March 18 Report Share Posted March 18 Yes you should be able to trigger the ground side of a standard relay (Pin 85) and use that to power the pump in standard mode. SidewayzSkyvia 1 Quote Link to comment Share on other sites More sharing options...
SidewayzSkyvia Posted March 22 Author Report Share Posted March 22 Went ahead and wired ecu straight to fp relay. Got the settings right in the ecu and problem is 100% resolved. Thank you guys for all the help. Quote Link to comment Share on other sites More sharing options...
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