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I finally bought an AEM a/f gauge, as I was having a lot of issues with rich, then lean ratio. I believe I have it fixed at this point, but as I haven’t yet installed my S300, I want to install the a/f gauge asap, and definitely want it there for tuning. Currently, I am not boosted. This is simply to be sure my a/f is healthy, and I don’t need to continue troubleshooting.
The directions are quite specific about where it should be installed, in what orientation, etc..
As I would like to use this first as just a standalone gauge, without connecting it to my ECU (yet..), I was wondering if I can keep both my upstream and downstream O2 sensors where they are, and use this 3rd bung for my A/F gauge.
this is about 6-7” from the flange for the cat, so it’s a little further downstream than their recommended 18” from the exhaust in the cylinder head.
I figure as long as the exhaust isn’t leaking ahead of the sensor, it should be good data.
Might as well wire it all the way to the S300 so you can actually use it for tuning. If it's just a standalone gauge it's not much more than a decoration and warning light. You're missing most of the functionality.
With the S300, there's really no point in keeping the stock sensors (either of them). The ecu can use your new wideband sensor just fine and the downstream sensor is doing absolutely nothing... it's not even connected to anything.
52936359[/url]]Might as well wire it all the way to the S300 so you can actually use it for tuning. If it's just a standalone gauge it's not much more than a decoration and warning light. You're missing most of the functionality.
With the S300, there's really no point in keeping the stock sensors (either of them). The ecu can use your new wideband sensor just fine and the downstream sensor is doing absolutely nothing... it's not even connected to anything.
Believe me, I agree. Unfortunately, since I know nothing yet about tuning, I’m not ready to move the S300 over in place of the stock ECU. I’ll wire everything, of course, for future connection, but I figured at least this way, I’ll know if I’ve got a dangerous mixture that’s damaging the engine.
really looking forward to getting it tuned.
on that note, I have a higher volume fuel pump (Walbro 255lph), and some FIC 355 fuel injectors.. is there anything I can do to improve airflow prior to adding forced induction, to allow a bit more power while tuning? I want to get a turbo installed eventually, but no budget yet for that, and with this being my daily, until I fix the transmission in my other ride, I’m not going to be doing any major projects on it in the short term.
The reason you want to wire it to the ecu is because you're not going to learn anything with it as a standalone gauge. Say you're driving around and you see a lean number on your gauge. What RPM are you at? What's the MAP value? The throttle position? Are you going to stop and try to write that down so you can go look it up later and try to make a change? Or just try to remember? It's one wire. Hook it up to D12 and set it up in the S300. Your narrowband is useless for what you are after, it can only show if you are rich or lean - no number - and does absolutely nothing for you at greater than cruise load where you are after a stoichiometric mixture. Plus, you don't have to waste time and money welding in an extra bung.
The good news is that you're not likely to blow up your stock NA D or B series by running it a bit lean. You might knock it a little, but that is far less detrimental in a stock compression ratio NA engine.
You say you don't know much about tuning... have you adjusted your calibration for your larger injectors, or are you just running around on a base map? If so, start there. You can't just add 50% larger injectors and have it run correctly without tuning.
Based on your signature, you've done all of the basic stuff to increase airflow on your otherwise stock engine. Next step would be to make sure it's 100% healthy (good compression and leakdown numbers) and caught up on maintenance, free of leaks and all fluids fresh. Cap and rotor, plugs, good quality (Denso are great) plug wires, new belts, and then you can start playing with the tune. As I said above, you're in the sweet spot for learning since it's highly unlikely that you're going to hurt a stock engine.
52936730[/url]]The reason you want to wire it to the ecu is because you're not going to learn anything with it as a standalone gauge. Say you're driving around and you see a lean number on your gauge. What RPM are you at? What's the MAP value? The throttle position? Are you going to stop and try to write that down so you can go look it up later and try to make a change? Or just try to remember? It's one wire. Hook it up to D12 and set it up in the S300. Your narrowband is useless for what you are after, it can only show if you are rich or lean - no number - and does absolutely nothing for you at greater than cruise load where you are after a stoichiometric mixture. Plus, you don't have to waste time and money welding in an extra bung.
The good news is that you're not likely to blow up your stock NA D or B series by running it a bit lean. You might knock it a little, but that is far less detrimental in a stock compression ratio NA engine.
You say you don't know much about tuning... have you adjusted your calibration for your larger injectors, or are you just running around on a base map? If so, start there. You can't just add 50% larger injectors and have it run correctly without tuning.
Based on your signature, you've done all of the basic stuff to increase airflow on your otherwise stock engine. Next step would be to make sure it's 100% healthy (good compression and leakdown numbers) and caught up on maintenance, free of leaks and all fluids fresh. Cap and rotor, plugs, good quality (Denso are great) plug wires, new belts, and then you can start playing with the tune. As I said above, you're in the sweet spot for learning since it's highly unlikely that you're going to hurt a stock engine.
Thanks for the feedback. My point is that I have a Z6 base map on the S300, and I don’t have the knowledge to tune it properly for daily use.
The injectors are not installed, they’re in a box, awaiting my brain catching up, so I can tune the thing properly, when something other than factory components are installed.
In regard to the health of the engine, I should be in good shape. Though the engine has over 200k on it, I’m the original owner, and know what’s been done to it for it’s lifetime.
I have a number of things on the to-do list, biggest being to replace the timing belt, water pump, all accessory belts. And while I’m in there, fix the crank seal leaking, and probably the crank sensor as well. The engine has fresh cap, rotor, coil, plugs (NGK) wires, several sensors, and all leaks are cleaned up, other than the aforementioned crank seal on the driver side (replaced rear main when I did the transmission / clutch / flywheel a couple months ago). Head gasket blew out about 2 years ago, and I should have done the timing belt and water pump at that time, but was in a time crunch, moving from Colorado to Texas.
previous compression numbers showed some lower compression in cylinder 1, but they need to be checked again. I’m hoping the head gasket replacement has addressed that, and it’s not rings.
GAUGE —————— ECU
BROWN (-) >>>>> D21 or D22. You can tap onto either of these wires.
WHITE (+) >>>>> D10. Cut factory wire at least 3 inches away from the ECU D plug. Connect BROWN wire to the short wire leading to plug.
*** solder all connections and cover with heatshrink tubing (WHITE) and electrical tape (BROWN)
GAUGE —————— ECU
BROWN (-) >>>>> D21 or D22. You can tap onto either of these wires.
WHITE (+) >>>>> D10. Cut factory wire at least 3 inches away from the ECU D plug. Connect BROWN wire to the short wire leading to plug.
*** solder all connections and cover with heatshrink tubing (WHITE) and electrical tape (BROWN)
Thank you! Those are the only 2 wires needed? I printed out the AEM installation instructions, but haven't spent much time on it yet. Thing is a book. lol
I do have a couple analog input cables that came with my S300, so I was planning on using that. Although, getting the wiring out from inside the ECU to outside the case would be a challenge..
Does anyone have a part number, or know where I can find this hose standoff part? I usually buy OEM parts from Hondapartsnow.com, as they seem to be pretty good about getting me the right stuff. Unfortunately, I haven't been able to ID this part, or find in their diagrams, or on alldatadiy.
I bought some high quality plastic epoxy (Fusor143), to patch it up. but was hoping to find the OEM replacement.
Since your ECU is all fancy with a built in adapter board, you want to wire the 0-5v wideband signal output from the gauge/controller to D7 on the OBD2a engine harness plug. Don't connect the signal inline to D7, cut the wire so the OEM o2 signal is no longer sharing the circuit. https://www.ff-squad.com/technet/wiring.obd2a.htm
Hondata will read the wideband on an analog input, but I'm not 100% sure you can utilize it the way a tuner would want. On the closed loop advanced tab is where you select the wideband input, which is default OBD1 D14, and this is also what hondata uses to log afr in tables, use protections, or use closed loop. None of the analog inputs are an option in this selection window.
I usually splice power and ground from the ECU's power and ground. Just make good connections with solder and insulation. Using the same voltage and ground sources as the ECU gives the least signal skew due to voltage reference differences.
Since your ECU is all fancy with a built in adapter board, you want to wire the 0-5v wideband signal output from the gauge/controller to D7 on the OBD2a engine harness plug. Don't connect the signal inline to D7, cut the wire so the OEM o2 signal is no longer sharing the circuit. https://www.ff-squad.com/technet/wiring.obd2a.htm
Hondata will read the wideband on an analog input, but I'm not 100% sure you can utilize it the way a tuner would want. On the closed loop advanced tab is where you select the wideband input, which is default OBD1 D14, and this is also what hondata uses to log afr in tables, use protections, or use closed loop. None of the analog inputs are an option in this selection window.
I usually splice power and ground from the ECU's power and ground. Just make good connections with solder and insulation. Using the same voltage and ground sources as the ECU gives the least signal skew due to voltage reference differences.
Awesome, that's a big help! So when you say to use D7, is that a digital signal? I want this to work the best I can make it, and if using an analog is not the best way, I have no reason to use the supplied adapters. Besides not being able to route it through the ECU case anyway.
I'm a little confused re: D7 vs. D14. I assume the wideband would use D7, being the factory upstream (primary) O2 ?
Notice the connector letters there. D7 means connector D pin 7.
OBD1, it's D14. You're using an OBD2a harness with no OBD1 plugs, so you have to go off the OBD2a diagram. That's why you want D7 on your harness, but you still call it D14 in hondata. The adaption is done in the red circuit board soldered in there. It's still an OBD1 ecu and hondata has no idea that the adapter you're using doesn't have any OBD1 pinout
Notice the connector letters there. D7 means connector D pin 7.
OBD1, it's D14. You're using an OBD2a harness with no OBD1 plugs, so you have to go off the OBD2a diagram. That's why you want D7 on your harness, but you still call it D14 in hondata. The adaption is done in the red circuit board soldered in there. It's still an OBD1 ecu and hondata has no idea that the adapter you're using doesn't have any OBD1 pinout
Ah, thank you. That clears it up. Yep, I printed out that reference. Thanks again!
Oh wow, where did you find one of those OBD2 headered ecus? Those things are really rare birds.
x2 on everything mentioned above. Use one of the extra ecu analog inputs. The s300 analogs are only for logging and are not directly run through the ecu hardware, and you won't be able to enable closed loop.
You have four analog inputs available. I'm not sure why everyone ignores it, but I prefer to use D12 EGR Lift Sensor input because I guarantee you aren't using it for anything else. I find the ELD extremely useful while tuning because it tells me in my datalogs how much I'm currently loading the alternator. Turning the ELD and alternator control back on after tuning is complete will also net you a small amount of gas mileage improvement. D14 NB02 requires hardware changes to read the full 5V scale. Hondata claims you need to add a capacitor to your board to make D12 usable, but I've run it with and without the capacitor and haven't noticed a difference. OBD1 B6 is also available and it's a full scale 5V input that's not used for anything else.
I'd check if there's continuity between OBD1 D12 (circled pink below) and your ecu's D9. Youu can also probe your ecu header and/or read the traces on the board to see if B6 (circled green) is connected to anything on the OBD2A side. Either of those are preferrable to D10 or D14, in my opinion.
52937146[/url]]Oh wow, where did you find one of those OBD2 headered ecus? Those things are really rare birds.
x2 on everything mentioned above. Use one of the extra ecu analog inputs. The s300 analogs are only for logging and are not directly run through the ecu hardware, and you won't be able to enable closed loop.
You have four analog inputs available. I'm not sure why everyone ignores it, but I prefer to use D12 EGR Lift Sensor input because I guarantee you aren't using it for anything else. I find the ELD extremely useful while tuning because it tells me in my datalogs how much I'm currently loading the alternator. Turning the ELD and alternator control back on after tuning is complete will also net you a small amount of gas mileage improvement. D14 NB02 requires hardware changes to read the full 5V scale. Hondata claims you need to add a capacitor to your board to make D12 usable, but I've run it with and without the capacitor and haven't noticed a difference. OBD1 B6 is also available and it's a full scale 5V input that's not used for anything else.
I'd check if there's continuity between OBD1 D12 (circled pink below) and your ecu's D9. Youu can also probe your ecu header and/or read the traces on the board to see if B6 (circled green) is connected to anything on the OBD2A side. Either of those are preferrable to D10 or D14, in my opinion.
Wow, thanks for the insight. I’m still too clueless to put most of that to use at the moment, but I greatly appreciate the feedback. I haven’t yet installed the ECU, since this is currently my daily and I don’t have any idea how to tune yet.
ETA: purchased the ecu from District Drive. He’s a great guy, and has been very helpful and responsive.
Thank you! Those are the only 2 wires needed? I printed out the AEM installation instructions, but haven't spent much time on it yet. Thing is a book. lol…....
to power up the gauge, you can tap into one of the auxiliary ports on the underdash fuse box for switched +12VDC powerr (#3 in the photo below). As for the ground, find a threaded hole near the fuse box and use the appropriate bolt to ground it
Air / Fuel gauge installation
