Liquidog

I have seen a lot of threads similar to this, but nothing quite like this.

1990 with DIYPNP built by me. 94 engine with turbo and RX8 yellow top injectors. Starts and runs with basemap, but runs pig rich and eventually stalls. Req fuel has been adjusted for the 420cc injectors. AFR table looks ok, I look at fuel table. I bump it down 10 points across the table (5 points at a time) and that helps it run longer, but it still eventually runs rich and stalls. If I remove too much fuel the car runs really lean and won't start at all. I bump the fuel back up. I use VEAnalyze but strangely, the numbers don't seem to change at any point in the rev range. I go to calibrate AFR. As we all know the AEM WB02 gauges are a total ************ to calibrate and I try a range of settings. But no matter what I do, the AFR gauge in tuner studio does not change while the car is running. So Tunerstudio always shows an AFR of 10, even when the gauge shows leaner by several points. I can get Tunerstudio to display a different AFR by changing the voltage settings in the AFR calibration window, but Tunerstudio's AFR gauge does not react or change when the car is running.

Thinking the gauge could be off, I test voltage output. It's within spec. (here's a neat link for testing your AEM gauge: DIY Testing AEM wideband gauges/sensors ) So it seems the ground is ok. It's grounded at the harness at the ECU on the black/green wire. I'm wondering if I have the white output wire from the AEM going into the right place at the ECU. I've tried both 2P (red/green) which is what flyin' miata suggests in one of their PDFs, and I've tried 2N (red/blue) which is what is identified in the m.net garage section somewhere. I have links if you want. Both 2P and 2N produce the same result - Tunerstudio still doesn't ever change its AFR. Which would jive with VEAnalyze never doing anything - if it can't read AFRs I don't think it's going to adjust. I guess it could also be the Bosch O2 sensor unit itself, I haven't tested that. But it was brand new.

What am I doing wrong? Tune file attached.

Akina_Downhill

iTrader: (1)

Your idle cells look very low. Are you sure it runs rich?
Just a pick a port under EGO Settings and feed the wideband output to it.

Liquidog

Which port though? It's set to Local, but there's also Remote ADC0, Remote ADC1, etc.
When you say "feed the wideband output to it".... how's that?

Thanks for replying!

Liquidog

And yeah, AFR is 10 on the gauge itself. You can smell the unburnt fuel in the exhaust. It runs really rich.

Akina_Downhill

iTrader: (1)

Do you have a map Hose connected?
Have you tested ignition and fuel on test mode?

Liquidog

Yes, the hose is connected to the Megasquirt and is routed to the recommended place near the FPR, tee'd into the line. I'm not familiar with test mode. I did get the car to idle last night by adjusting the fuel at low RPMs as you suggested. Tunerstudio still shows an AFR of 10 no matter what else I do in EGO Control settings or anywhere else. I'm wondering now if maybe I did a pull-up wrong when assembling the unit. I know I can keep playing with the fuel table to have a driveable car, but I'm hoping to get this AFR reading issue sorted out so that VEAnalyze Live can see actual AFRs and consult the AFR table to correct fueling for me. Obviously I'm not super great at this tuning business so I thought I'd get the software to help me out. Unfortunately since it's not reading AFRs correctly I'm just sort of bumbling around.

itsbendavid

I'm having the same issue my my car. 1993, with a MSPNP2 and Innovate MTX-L WB. The gauge in tunerstudio stays at 10 no matter what fuel load or RPM even though my actual AFR gauge reads different. Gauge is grounded at the engine, timing is good, TPS is good, MAP line is good, but I'm also running pig rich (low 12s at WOT, mid 13s at idle and cruise)

Could it be adjustment of the TPS is needed?

WigglingWaffles

I don't know much about RX8 injectors, but I hear the dead times on RX7 ones were extremely picky and have to be perfect to run smoothly
Could your req_fuel be incorrect for the injectors?
Did you calibrate the afr in TS properly?

Braineack

iTrader: (62)

instead of randomly connecting wires to random places, why don't you figure out exactly where your DIYPNP is wired to accept the wbo2 -- then connect to that?

Liquidog

It's not random, I researched it. The DIYPNP is set up for a 1990 harness, and I have two conflicting sources of information telling me where the O2 sensor comes in on a stock 1990 harness. I'm hoping someone can verify for me where they have their WB02 connected on their 1990 harness. In the meantime, I'm going to pull my DIYPNP unit and verify that the O2 connection in the unit is good.

Liquidog

I don't think it's the TPS adjustment, I was able to calibrate my VTPS without issue, and my car stays rich throughout the rev range.

Where do you have your WB hooked up to in the harness? Which wire? I have tried a couple, as I posted above. It seems like we're just missing a simple piece of information here that someone could easily provide.

Liquidog

I believe the req_fuel settings are correct. I had the RX8 injectors cleaned and flow-tested so I believe they are ok. I think the primary issue here is the DIYPNP not reading the signal from the gauge, which means the unit cannot be tuned in reference to the AFR table.

18psi

iTrader: (76)

why are people connecting widebands to oem wiring harnesses? what am I missing here?
every..single...ms unit ever made has a specific wideband input that you can use specifically for this

YeboGoGo

iTrader: (1)

Seen this a few times before

Odds are you have the old narrowband sensor connected as well as a break out for a wideband.

Disconnect the narrowband and see if it helps

Braineack

iTrader: (62)

it is random until you open up the unit that someone built and see EXACTLY where the wbo2 input is wired.

I could put a wbo2 input on the purge canister solenoid if I wanted to...

Liquidog

I'm probably not making myself clear here. I built the unit. It was earlier this year and I don't recall exactly where I set the 02 input, though at the time I thought I was wiring it to the stock location on the stock harness, which would make installation of the WB02 as simple as just finding that particular wire in the harness and grabbing a power and ground. Anyways I'm going to pull the DIYPNP and check and see. That was always going to be the next step, but I put up a thread to see if there was anything else I'm missing.

Liquidog

Maybe that's my mistake and it's ME missing something. I thought the process here was to build the DIYPNP like it was going to use a OEM O2 narrowband, and then just take the WB02 output from the gauge itself, and run that wire to where the narrowband would normally be sending its signal, if that makes sense. I just tapped into the OEM harness right at the ECU connector. This is my first DIYPNP and I couldn't find great instructions for doing things the tidy way with the DB connector. I'm not a wiring whiz. I did a lot of reading but after a while it all sort of blends in together. I PM'd Brain for one of his units many times and never got a reply so just doing the best I can. Thanks to everyone for your responses!

18psi

iTrader: (76)

I'd say unless you plan to use the unit with the stock narrowband at some point, just yank it out, figure out where your wb input is, and run it separate and not through the oem harness. This way you can easily troubleshoot, and have a strong, clean, uncompromised input to the ms from the wb.

Getting ahold of Braineak is impossible. Just leave a message with one of his cats

Liquidog

ahhhh ok. I'll check for that too while I'm in there. I don't think I understood that I needed to pick and choose which one was connected. I probably did both and have been sending the WB gauge signal into the narrowband connection, where the DIYPNP isn't looking for it.

My confidence level while building the DIYPNP fluctuated between "this is simple, I can build computers, this is easy" to "OMGWTFBBQ HOW DO I MAKE A WIRE TALK TO ANOTHER WIRE"

Liquidog

I will probably never use the stock narrowband so that makes sense. I'm guessing I need to use the DB connector to do what you're describing so I guess I'll have to figure that out.

Also, lol @message with cat. Maybe I'll send my cat over with a tiny scroll or something.