Lexi2pnt0

Hey,
Just did an engine swap to replace a running 1JZ in my SC400. The previous engine was running, but had spun a bearing. After the new engine, the car starts perfectly fine, however it will stumble when I start touching the throttle. It is a stock (1JZ) engine, but has the following:
-Borg Warner S360 Turbo, PN 177272, .91 A/R divided housing
-CXRacing thick walled 11ga Stainless header, with WG flange converted to 44/45mm V-band
-Turbosmart Hypergate 45mm Wastegate
-3" Stainless CXRacing downpipe w/2nd O2 bung added and BW Marmon flange welded on
-4" turbo 45* polished aluminum intake pipe
-AEM 320lph fuel pump
-Denso 650cc injectors
-Greddy Emanage Ultimate
-Greddy "T13" PNP Harness

It currently has -14 to -17 of vacuum at idle, and it is throwing a CEL code stating a knock sensor fault.

So does anyone have any thoughts? Is it the faulty knock sensor? A vacuum leak? Maybe an issue with the the wiring (there were a few things addressed in the swap)? Or is it Maybe just an issue with the fuel mapping with the piggyback?

Please let me know if you have any thoughts. Does anyone maybe a good base map for a 1JZ with the Greddy eManage?

I just want to get her going!

Thanks in advance!
Chris V.

LoveSCs

iTrader: (2)

Do you have a wideband? If not, then get one. Every non stock car should have one. That would tell you if your mapping is off. It could be stumbling for a number of reasons. First thing is to fix what you know is wrong, so start with the vac leak. Then once you know if your fueling is correct under throttle via wideband, then you can cancel the fueling out. If there is a faulty knock sensor, that could be causing a pull in timing

Lexi2pnt0

Thanks for the response. I do have a wide band, however I think it reads incorrectly. It reads lean, but the car shows symptoms of running rich. I just pulled the plugs and they we're on their way to being fouled. I'm wondering if the position of the 02 might be bad? Does it matter where it is, as long as it's in the exhaust side of the turbo? The knock sensor is intermittent, and the car runs the same whether the light is on or not. So though that might be somewhat of an issue, I don't think it's the main culprit. As far as the wideband, is there a difference in the readings between when it's at idle and when it's moving? I don't know if the lean reading are normal when it's just sitting still.

Thanks again in advance!

tjmhillz

iTrader: (6)

How old is the wideband sensor? Does it only stumble at idle or anytime you touch the gas? Was the car tuned? can you post a pic of where you installed the wide band.I would double check all vac lines even the smaller one as it could be a leak somewhere.