Well, I've been trouble shooting a strange issue where in the warm/hot afternoon it runs really lean but in the mornings it runs pretty rich/good. Like AFRs 13-15 in the AM and like 14-19 in the PM (at times it wants to stall at like 18-19 AFR). I've gone through and reviewed logs and made some tweaks but I can't seem to find anything that would change how it runs based on outside or intake air temp. Engine coolant temp is consistent in the morning and afternoon and in any case the air is less dense when it warms up so it should just run richer in the warmer temps. IAT is defaulted to 68f all the time.
It's going to be really hot this week (really hot is 94f) so I'm going to try and park it tomorrow then fire it up 'cold' in the afternoon and see how it runs from the get go. I have a hunch that it could be weak wiring to the fuel pump and it's not building enough pressure (from my research?). Fuel filter is brand new. Pump is unknown. Yea, I could test the pressure, but I might as well just get a walbro if it seems that's the problem.
If you guys have any other ideas I'd be glad to hear them.
Scoot, Thanks for the idea but I don't have a MAF with an IAT. I'm using a stinking KA single cam MAF.
Didn't run too bad in 94f temps coming from a cold start.. So I'm not sure exactly. something getting heat soaked or some shit. Walbro, IAT sensor, on order, just need the MAP sensor. Soon.
Sorry, testing gopro locations, this was underhung from the sunroof.
Ok. It already has a walbro. I rewired in a relay to the pump and no luck figuring out whats up with the high AFRs. It happened again, after getting the underhood temps up, but, when I left the hood open the issue seemed to go away. ?? I don't know?
Going to PIR for late night drags tomorrow. We'll see what happens. Maybe, low-mid 15s. Test and tune I suppose.. https://youtu.be/XpuITbmEPTo
Well, it has been a busy summer! Haven't been driving the shitbox too much as I was waiting on the pressure regulator, but it doesn't seem to have helped.
I'm still fighting this damn lean issue. Runs awesome in the cool mornings, runs like absolute crap in the hot afternoons. Rewired the Fuel pump to a relay. Replaced the FPR. Something is getting hot and not working right. I took it for a cruise after putting in the FPR and it ran great, just when it gets 'heat soaked'.
EDIT: scratch all that shit. It must be the MAF? Brand new KA24E unit. Voltage at Idle in the morning is ~1.6V, in the afternoon when it runs lean it's ~1.4V. Going to do some testing tomorrow... Dammit. Pretty sure someone suggested MAF above.. the heat must fuck with it just enough to cause the misread.
After some research, I decided I am just going to a speed density based tune and am going to ditch the MAF. Just need to get the IAT bung welded up this week/weekend and drill and tap the intake mani for the MAP sensor. You're not supposed to use the Boost Sensor(PSIg) as a MAP sensor(PSIa), FYI. https://www.aemelectronics.com/?q=products/sensors-connectors-accessories/map-pressure-sensors Although the specs look very similar between the Brass PSIa and SS PSIa sensor..
I'll also be installing the MAC boost solenoid to control boost through the ECU.
Need to do some more research and attempt to calculate VE, but that'll probably come with time and 'tuning'.
Edit Update: Ordered new 'ebay' exhaust, just something with a muffler that's not 'ricey'. Ordered new temp sensor for gauge cluster. Getting the IAT bung and a radiator temp sensor bung welded up soon. MAP sensor will just use a short vacuum line to the TB. Wiring still todo and maybe a compression test.
Body & Paint, wheels, brakes, hubs, suspension, LSD, turbo, and injectors, being considered. Cleaning/Prepping garage for work this winter.
Edit: Bungs welded
Wiring up the IAT and the MAP sensor.
Tuning so far has turned out to be, well, not simple or easy, once I get it happy, I'll make some videos. Another note, is do not mount the MAC boost solenoid directly to the chassis, it's super noisy, clickity clickity, needs a rubber isolator or something..
Tuning has been coming along albeit a little bit slower than anticipated, but it's getting closer. Idle, lower RPM, midrange, and low boost AFR's are solid.
However, I kept having this problem at WOT where it was just cutting out and reading lean but I could see inj. pulse width rising. I knew it was getting fuel but just not enough spark. Tried some BKR6E plugs gapped at .028, no luck, and after some research I ordered 4 brand spanking new OEM coils (they came from Olympia Nissan and were packaged like a Hickory Farms gift box) and ditched the cheap knockoffs (maybe ISR?) and it fucking finally, cleared up! Now I can actually go WOT through the rpm range, however the rain makes it mostly impossible to safely do pulls, but there's some good weather coming this week and weekend and I'm going to get out and rip it up and finally get the WOT part of the map dialed in!
I've done some research, but what do you think the Stock t25 turbo max boost is? 10-12psi?
I'm considering a GTX2863R but might go with GTX2867R, want a reliable 350whp or so. I put one in my 'shopping cart', but didn't pull the trigger, LoL. Needs fucking brakes and a lsd before a bigger turbo really.. Christmas is right around the corner though..
Good things are coming. Garrett GTX2863R 0.64 Turbine Housing. 740cc injectors on order. I will run this next summer, then get some cams and that'll be about all for the engine. Then focus on brakes, diff, suspension.
A little playing around with the gopro, nothing too exciting.
Speed density is working out pretty good. I keep fucking with it trying fix some minor nuances, like high idle during warm up and some weird high afr under very light acceleration in vacuum, but can't seem to get it quite right. Over all was running great on the stocker at 11psi.
Agree on the Electronics. I had to get genuine injectors this time because once I bought some cheapo ones for my RX7 on ebay, big mistake. Didn't flow right and inconsistent spray pattern, I ended up just throwing them in the trash and got some RCs.
Anyone got thoughts running 24psi on the 2863 with aux injection?
I will probably get out to the dyno next spring/summer just to get a professional opinion about my 'tune'.
Edit: got this bitch out tonight.
Ported wastegate and installed actuator.
Locktite and an impact gun that I used to take them off. Then wacked them another 1/8-1/4 turn. I did not set the backlash. I made sure not to mix up the shims and didn't notice any abnormal wear on the pinion or the ring and just said fuck it.
Never heard of spirit peaks. I might try to get down to parc sometime though..
Spirit Peaks is in South Toutle, WA. A wider track than PARC and is a bit a of a drive, but from what I see from posts it looks like a good time. Someday I might make it out there, when I get either a welded diff or 2-way in my car.
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