rb25 tuning need help

[skyline084]

My rb25 just started to hesitate,baackfire than stall out. It only does it after driving for a while and usually during cruising.
That being said, I am looking to adjust my air/fuel. I'm new to this part, so don't know if the apexi safc would be all that i need? or if i should go with another ems and get rid of the maf completely..
anyone who's had experience, please help

[TheRBguy]

Depending on how much your air fuel ratio is off would depend on what route you could go too. An afc is for fine tuning you cannot make large adjustments with one.

[skyline084]

Okay, I am keeping my motor stock for a while, and am not going to be making huge adjustments i wouldn't think. If i go with an afc, does that read whether i'm running lean/rich? or would I have to buy a wideband too.

Or how difficult would it be to just replace my ecu with say a greddy e-manage or something?

[skyline084]

I understand now a bit more.. A wideband with a gauge to get an accurate reading of air/fuel. Than the AFC to make the adjustments.
To install the wideband, do I keep the factory 02 sensor in? or do I have to make a separate hole for the wideband 02 sensor?

As for the AFC, do I need a computer program to make minor adjustments? or are all adjustments made right on the controller.

[TheRBguy]

I dont believe most afc's read air fuel ratio, you would probably have to buy a wide band too. A wide band is always a good thing to have. If you are running a stock setup an afc would probably be fine.

[parkerj2]

Sounds like you have a problem. IF its been running fine and now has issues an safc wont fix it.

[TheRBguy]

I missed that part if your motor is bone stock then you might have a problem, and yes you keep the stock o2 sensor in and drill your downpipe and weld the aftermarket sensor bung in that comes with the wide band. I would suggest buying an AEM wide band they are very accurate.

[silviasgp06]

not sure what the issue is. Please list more deatails about how and when the cars acts up.

but you shouldnt need to buy an SAFC to get the car running right.

Find the main issue and the car should run fine no matter how long you drive it.

main things to check for(but please be more descriptive on how the car acts up):
spark gap
good/bad maf
boost leaks
coil issue
ground issue
bad wiring/sensors

chances are, me or someone else on here will be able to tell you what specifically to check and fix if you detail your issue

-Daryl

[skyline084]

Okay here's my issue. The car has been running solid for three months as a DD. Up until about a week ago, when I was just doing some normal driving. The RPMS jumped, the car started to backfire, than it would just die.
I believe it's something with the MAF, because when I started this motor for the first time, it would do something similar,(stall out on boost or heavy load) until i used electrical parts cleaner on the maf which is what fixed all my problems. Until now.
I don't think it's a boost leak.. my intercooler piping is bolted down tight, and my vacuum lines are all new
Spark plugs were done by a shop, so I assume they're fine. Plus i haven't changed anything and the car was running good.
What would i check on the coils to make sure they're good? 12v source and signal?
ALSO-- I just got code 54, which says to check A/T circuit going to ECU which is for automatics only.. Mine is a manual. Does this mean my ecu is meant for an auto? and does it matter?

[TheRBguy]

I would just get a new maf sensor they are pretty cheap.

[skyline084]

The cheapest I've seen the j60 maf for is 80. I just cleaned the maf, and air filter. I had no oil on my filter so maybe dirt was starting to get in.. or salt from the roads..idk

[skyline084]

still did it but not nearly as bad.. just gonna try a new maf

[skyline084]

Okay im in need of some serious help. Yesterday the car ran almost perfect, it hesitated twice and didn't stall. Today, I couldn't get more than five miles before it stalled. Than it kept stalling and backfiring. Couldn't even drive it, had to park it. It doesn't show any codes, but randomly will show code 54, which is A/T circuit to ECU.
Has anyone had this problem?? Car hesitates,backfires than stalls.. and the RPMS are all over the place. Doesn't matter if it's idle/cruising/boosting.. it's completely random
I cleaned MAF with electrical parts cleaner, and cleaned filter.