2jz gte swap - running too rich ????

CzA

New Member
Jan 15, 2007
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Toronto
I made a post in the wrong forum section, so ill just copy and past eit in there, with the replies too.

my friend has an 87 mk3 an di just did a 2jz gte swap in her. he is running rich and i don’t know why.

his wideband shows at idle, 14.8, WOT = 10’s, 100km/h = 14.8. It has intake done with three inch piping, stock twins running around 14 psi, 3inch exhaust, walbro fuel pump, stock 440’s (jdm engine), it has the tpc mod, but its currently disengaged. it will fluctuate from 11.9 to 12.3 at idle. Any ideas why she is running so rich? anything i can look for?

Replies-

14.8AFR at idle and cruise is where your AFRs are supposed to be at. 14.7 AFR is considered stoich; means every oxygen molecule is mixed with every fuel molecule and burned equal with no oxygen or fuel left over. Just about every car i've seen runs in the 10AFR at WOT.


thanks.
 

rakkasan

Currahee!!
Mar 31, 2005
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I don't know who posted that reply, but 10.0 AFR at WOT is too rich. It could be even richer than 10.0 because on most widebands, that's the lowest AFR displayed, so lower is definitely a possibility. I want my car at 11.8 at WOT
 
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CzA

New Member
Jan 15, 2007
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Toronto
from what i know, its a stock non modified ecu. Any way i can check to see if it has been modified?

Lets assume its a stock ecu, what would be other reasons for me running so rich?
 

StiCk3

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Apr 25, 2009
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AFMor TPS malfunction, defective FPR...could also be the ECU itself crapping out. A lot of possibilities.
 

CzA

New Member
Jan 15, 2007
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Toronto
well i went to the dyno today to see what’s up. At 17 pounds i was making 380 HP / 370 Tq but Way too lean as i was at 15 for afr’s, so i brought it straight back down to 13 psi. I don’t have another ecu to test out. I have 550’s ill be putting in shortly, and i do have the 255 LPH in there, and i plan on getting a afc controller too. I’m just new to the 2jz world so im not too sure whats normal (if there is such a thing) is for WOT @ 14psi on stock twins (japan spec).

Thanks.