Another wierd tuning issue, multiple symptoms, please help, I've looked
#16
Yes, see if you can adjust the fuel pressure down to 33psi, and what it is after you pull the vac line.
Still no trims after idle for 20 minutes... I don't know what to make of that.
#18
No STFT or LTFT or both?
I fixed the check valve connection to the valve cover, good to go, held on for a brief test tonight in boost, that ended up way lean.
I checked the spark plugs and they looked good, except the white inner tips are no longer white, they are orange. THese are the IGR7A-G gapped at .24... I went ahead and put my Denso IW24's back in. Gonna run a test there, and see if literally, the spark plug gap is what is causing this(very hesitant). Also, 2 of my spark plug boots that connect to the coil, are a little melted on the inside around the wire clip or coil in the well that connects to the spark plug. I cleaned them out, and cleaned them up, hopefully that isn't a big issue either...
I get STFT and 02 feedback, but no trims. Drove for an hour, and nothing. I played with Periphery and all the rear o2 stock tables as well as the tephra patch. No dice.
Also no boost, can't get below 12 AFR's no matter what. Correction, plenty of boost, NO FUEL. Whether I dial up the injectors latency, lower the size scaling, nothing. She wont go below 12. Played with MAF Adder too, no joy.
Nothing has changed since the other day, when it was almost dialed in, except for trying to squeeze gas mileage out.
What circuit are the trims on in the ECM? Any way to test if I dorked this unit too, since I dorked my last one with a similar short on the fuel circuit?
Almost ready to part out and just say **** it.
I just have a sneaky suspicion that Pin 39 is the culprit, and the fuel pump is no longer going over to high speed. I have tested the actuator in EVOScan, and can hear the fuel pump kick on when activated, just not sure if it is activating the 12v mode or 8v mode...? Don't know if what I see at start up represents that High SPeed is working under boost...
Last edited by Raceghost; Dec 4, 2016 at 12:34 AM.
#20
So I may have found it. Since I am still running the EGR on my setup(Why...I am beginning to ask myself...) Either way, bottom side of the intake manifold, the black w/yellow markings hose fell off the EGR Vacuum regulator solenoid valve(the only one not zip tied under the hood.) Again, not sure if this is the problem child, but any thoughts? Ziptied it up, and will test in the A.M.
Last edited by Raceghost; Dec 4, 2016 at 12:35 AM.
#22
Ok, so been through the whole system again, looking for leaks. It looks as though my exhaust manifold gasket is leaking on the bottom side of the manifold/block connection. See some oil and carbon deposit on the block. Would this cause a Lean condition?
#23
Evolving Member
iTrader: (2)
Any exhaust leak before wideband O2 sensor can read lean.
Usually cold air causes lean AFR (not a lot, but more like 0.3 or so in my case) in open loop, and you can play with air density vs temp map to compensate it a bit, but not always easy because IAT sensor is kind of heated inside engine room, and aftermarket open-type air filters also sucks in heated air also. But if you change the value where your IAT reads, you can change the AFR.
I also experienced weak fuel pump can give about 1 AFR lean condition. I always thought fuel pump just dies before getting "a bit" weak, but it can also happen.
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Raceghost (Dec 5, 2016)
#24
Any exhaust leak before front O2 sensor can make ECU think it needs more fuel.
Cruise STFT registers +/- 2%, trims still not working.
Any exhaust leak before wideband O2 sensor can read lean.
Usually cold air causes lean AFR (not a lot, but more like 0.3 or so in my case) in open loop, and you can play with air density vs temp map to compensate it a bit, but not always easy because IAT sensor is kind of heated inside engine room, and aftermarket open-type air filters also sucks in heated air also. But if you change the value where your IAT reads, you can change the AFR.
Can you give me table names for 94170715 ROM. I think I know which ones, but would like clarity.
I also experienced weak fuel pump can give about 1 AFR lean condition. I always thought fuel pump just dies before getting "a bit" weak, but it can also happen.
Pressure reads 44 psi vacuum disco'd on AEM.FPR(Kelford 272 Cams) and 40 connected. Vaccuum on AEM.Boost gauge reads 12~14 ish at idle.
I can trigger the fuel pump while car is off, and hear it kick in to what I assume is high pressure mode via EVOScan
I relooked at logs, and it was running fine under conditions listed above, changed spark plugs like I said, and coincidently **** hit the fan. Then yesterday I found the vacuum leak on the egr, and fixed it hoping that was it... no dice. Can't figure out what the heck is going on.
#25
Evolving Member
iTrader: (2)
It is called "Relative Air Density vs Temp for Airflow/Hz" table.
The stock value is ideal value for air, but I bumped a bit for colder air temp to make the AFR difference smaller.
When I was dealing with this weak pump problem, I was surprised it was responding to ECU changes like injector scale, but it always reads about 1 AFR leaner at WOT loggings, fuel pump swap corrected the problem right away, not sure it is your case though.
I saw LTFT is not moving when front oxygen sensor is dead, but the oxygen sensor was giving lower voltage even at rich condition. Denso aftermarket O2 sensor is pretty cheap like $35 or so, if you haven't changed it yet, I strongly recommend to change it, also in case you use Invidia O2 housing where O2 sensor position is different, this sensor has a bit longer wire so no need for extension.
Hope you can find solve the problem soon.
The stock value is ideal value for air, but I bumped a bit for colder air temp to make the AFR difference smaller.
When I was dealing with this weak pump problem, I was surprised it was responding to ECU changes like injector scale, but it always reads about 1 AFR leaner at WOT loggings, fuel pump swap corrected the problem right away, not sure it is your case though.
I saw LTFT is not moving when front oxygen sensor is dead, but the oxygen sensor was giving lower voltage even at rich condition. Denso aftermarket O2 sensor is pretty cheap like $35 or so, if you haven't changed it yet, I strongly recommend to change it, also in case you use Invidia O2 housing where O2 sensor position is different, this sensor has a bit longer wire so no need for extension.
Hope you can find solve the problem soon.
#26
It is called "Relative Air Density vs Temp for Airflow/Hz" table.
EDIT: I think this is the one, let me know.
Thanks
Last edited by Raceghost; Dec 5, 2016 at 11:26 PM.