Blackzenki82

so yeah, i called some friends, asked them, did some research on the intarwebz... and couldn't come up with a definite answer, so i'll run it by you guys...

everything before the swap ran AWESOME, high 12 sec car and all, smooth idle, no problemos....

now that that's out of the way, here's the symptoms... when i rev up and get into boost, around 4-5K RPM it bogs like a SOB, watching my wideband, i see it getting richer and richer as the boost rises, and than WHAMN!! it leans out, off the gauge... WTF....

i've tried 2 different ECUs, a stocker, a GRID tuned, and even my Nistune with the S13 SR20DET base map... i've turned the GReddy Profec B spec 2 off, and on, and it does it either way, at the stock 7lbs psi, and the daily setting on the EBC of 11.5... it's like as soon as it hits full boost, on either setting, it just leans out... like a fuel cut..

also, when the idle sits "low" it sits around 1200K, and then slowly as the engine warms up, creeps up to 200-2200K rpm and stays there... this i attributed to the bad coolant temp sensor i had so i went ahead and replaced it with a new OEM unit...

i've checked all couplers, and vac lines (low idle is @ -15/16Hg), and then rechecked them all.... i went over the couplers twice, three times, and tightened all the clamps... nothing seems to work...

my motor is set up EXACTLY the way it was when i had it in the gold car...

my thoughts on possible problems-

Faulty MAF
possible (although unlikely), boost leak
IACV going bad

I'm lost, so if anyone can help, it'd be greatly appreciated

lordofthemiasma

Im going with maf.

Blackzenki82

yeah possibly... i checked all points on my harness, those two gounds at the top of the back of the intake mani were hand tight, so i went ahead and get em bolted down... idle is A LOT smoother now, BUT, it's surging, 1k-2k-1k-2k etc, and it still falling flat on it's face at exactly 4-4.5k rpm (just checked after tightening grounds)

Blackzenki82

no one else???

+Waldo+

if maf was faulty it would be running like shit, and cutting out at 2500... but thats if it is completly gone, not going out but i have never seen a in between stage lol.


double and tripple check harness would be my guess, if its the exact same way you had it before then its bound to be something not pluged, or grounded right.

good luck

Blackzenki82

i already double checked it... i only touched one section, and that was the excess 2ft, and i cut that length out... and since i was so worried about screwing something up, i did it wire by wire.... cut, solder, heat shrink...cut, solder, heat shrink... one by one, and not a huge mess... i then taped it up and ran it out....

i just can't figure out why it would instantly go lean at around 4-4.5k... like a feul cut...

i'll check grounds for the 4th time, maybe even add a few here and there...

rb_s13

Where did you wire the grounds in for the maf? I have had similar problems on a couple of sr and rb swaps ive done and 75% of the time they are fixed by rewire the grounds on the maf to a good ground.

Blackzenki82

i'm begging to think the same thing... i hadn't touched the MAF wires... but i think today, i will go over that section of the harness (untape it, resolder, repair if needed), and see if that doesn't solve the problem....

the damn thing ran PERFECT before the swap... clawhammer knows, he had the envy lol