Sr20det boost cut/ studder

[SilviaT]

Sr20det redtop in s13 hatch
relocated battery
Enthulapy tune
440cc injectors
N60 maxima mafs
12psi t28 turbo bottom mount internal waste gate
Greddy rs bov relocated
Cat delete/ headers/ emissions delete
NO wideband :(
NHL bkreix7-11 gapped at .025..
Dash readings are in km/h btw haha

Whenever I give it wide open throttle (even in nutral) it will have a sort of rev limiter at around 3,000rpm and won't produce any power...
I replaced my mafs since it was bad and now this is happening.. No codes are showing up. only 55 (no problems)
It will build boost/ power up to 3k/3.5k in all gears then cut out under load... In neutral I can rev up to redline if i don't FLOOR it..
Running very rich. Black residue on bumper. Plugs will be black in a couple days and WET with fuel.. All plugs are the same.
My next step is having a safc 2 installed and dyno tuned since I have no a/f gauge......
I have to clean my plugs every couple of days or else it will flood and not start in the mornings. It's been very cold out the past couple months if that makes a difference at all. Probably not.. Idk I just need some feedback!

Here's my video of it cutting out. Sorry for the low quality.
I was driving uphill BTW! I'm just giving it halfway throttle going to my house and when I give it a load after 3k it studers and almost sounds like a rev limiter!
Wtf.. If I put it like foot to the floor in neutral it will even cut out. But half throttle I can go to redline in nutral. But under load is all bad...

Sr20det cutting out at 3k under load. Help!? - YouTube (http://youtu.be/KxAd-eCVGP4)

[SilviaT]

NGK*** bkr7eix-11**

[ultimateirving]

Sounds like a maf issue, with what ur explaining. Especially since that happened after you changed it. Start by unplugging the new maf and revving see if issue remains or changes to something different.

BUT it also sounds like a bad vacuum or boost leak, so pressurize the system too.

[SilviaT]

Thank you for your response!
Well I bought the maf used and it was in much better shape than my original. It even took the code 12 away after I installed it. When I unplug the maf, nothing changed. But when I plug it back in; it stumbles down to low low Rpms then comes back up to normal (850/900)
And I don't believe i have any vacuum leaks.. I've checked many times and my hg is at -20....
Hmmm.... Maybe the maf was half bad all along and the computer doesn't throw a code?....

[OrangeVirus1]

if you have to clean your plugs every few days..... jesus you have a lot more problems then just a cut @ 3k rpm...

if the maf is bad it could be reading a higher voltage, telling the ecu it is getting more air then it really is, and dumping more fuel then you need. if the voltage isn't out of range of what the stock ecu will accept, then it won't throw a code for bad maf. per example : lets say at 3k rpm depending on throttle position the ecu will accept maf voltage ranges anywhere from 1.5v-3.2v ( just an example ) lets say the maf is dead and reading a constant hmm 1.6 volts. the ecu will say " that is within range and = xxx amount of fuel" and pour that much fuel. but when you rev the engine to like 3500 rpm the ecu is look for Maf ranges from (example) 1.8-3.4.. that 1.6 isn't gonna cut it and the ecu might cut fuel / ignition. at least this is what I have seen on my mazda which has a maf

Get a wideband, it is like engine insurance.

or it could be a shit tune

having hg-20 doesn't mean vacuum leaks don't exist. although I don't see a vacuum leak making this happen

[SilviaT]

I'd say once every ten days but yeah I like em clean! And it's obviously running way rich and that's what I'm trying to resolve..

[SilviaT]

For sure well I may just get a new mafs.
And does enthulapy warranty they're Ecu's?
I'm pretty sure my tune is ok but I will make a boost leak tester and replace my mafs..
And clean my plugs (;

[SilviaT]

When I ordered my ecu from enthulapy, I asked the owner of my local shop (who made the order and install) what my tuning specs were and he told me 440cc with n62 mafs.
Buuuuut I have a n60.. I had a n60 before and since it went bad, I just replaced it with another n60. That's before I found out my ecu is tuned for n62 (apparently)

[OrangeVirus1]

so try an n62

[SilviaT]

Will do. Thanks for your advice about voltage though that was great!

[steve shadows]

Eeeeehhhh. I would stay away from the SAFC, the Enthalpy tune should be plenty fine the way it is. If you want to scale fuel get an adjustable fuel pressure regulator but in my experience AFC just hacks up the signal to your ECU for the most critical sensor on the car, the maf and adds resistance to it in addition to not being a very good tuning device overall. If you want to get elbow deep in fine tuning pick up a PFC or Haltech. :2c:

[OrangeVirus1]

AEM FIC is pretty easy, and controls fuel trims all the way from +100% to -100% and does not hacking of ecu commands. you can control maf voltage completely, scale the maf, clamp the map, emulate 02 sensors etc

I will be tuning my RB20 on aem fic

[SilviaT]

UPDATE.
Bought a used n62 mafs off my shop for $50, plugged it in, and no more cut! PULLLS hard! got up to like 7lbs and i was back in my seat. Built boost up until about 5k a couple of times and everything sounds great/ feels great. Whoop whoop

[OrangeVirus1]

nice! congratz on the fix!