chejos13ls1

iTrader: (4)

ok,straight to details, 99 ls1 swaped 240sx running on speed density tune,also running only on the 2 fronts o2 sensors,edelbrock fuel rails with a aeromotive fpr,(pic attached for reference), frost tune for all of that, car is been running for at least 2 years now, never had this problem.

Car is bogging and sometimes backfires,and its really low on power,it all started all of a sudden,also when i removed the spark plugs only the the driver side bank(1,3,5,7) where super rich(more like completely black) ,passenger side plug's (2,4,6,8)looked normal,i've checked voltage on the fuel pump,voltage on the coils,and did a visually inspection on the o2 sensor on the driver side bank.....any other ideas?





the return is at the bottom of the regulator, the feed will be running to the 2,4,6,8 injector bank first, then tru the crossover to a dead end at the back of the 1,3,5,7 bank


thanks in advance

usmcpi

iTrader: (2)

You read any codes? I don't know if you swapped the car or not, but the previous owner may have pulled the bulb for your check engine light like the previous owner did for my LS1 swapped rx7.

RPM Graphics

iTrader: (26)

i'm having the same problem with my LS1 swap. driver side running rich & all the plugs have a dry black carbon on them. runs good in park but once i drive it down the block it starts to miss & sputter. i disconnected my O2 sensors & it runs much better. my tuner seems to think i have a bad O2 sensor. i'm just waiting on a scan tool to confirm.

LS100CAMSS

If it's running THAT rich, there should definately be some codes set. Like BANK1 STFT rich, P0300, etc. First thing I would do is find a scan tool that will not only read both current and history codes, but can also monitor live data. That being said, my first reaction is to think that your B1 02 sensor is giving the PCM an incorrect lean reading, causing the PCM to add fuel to B1. At any rate, you gotta have a scan tool to diag. Good luck. Cool swap.

LS100CAMSS

Is your guage mounted on the return line? May wanna move it to the inlet on the rail so you can monitor pressure at the rail.

norris.doug81

have 2000 T/A ls1 same problem exact same problem. my car puts codes out p0131 and p0405 i can erase the p0131 code no problem but the p0405 code comes right back after erasing without the car started the p0405 is an egr code low voltage the p0131 code is o2 sensor bank 1 this all started when i left the car sit for 2 years when i bought the car the lot said they upgraded the comp to a 2002 version by removing something maybe smog pump or something i think my comp needs reset now

Fosnot

iTrader: (15)

Sorry to resurrect an old thread, but did anyone figure out what happened here?

RPM Graphics

iTrader: (26)

mine was crossed O2 wires on my stand alone harness.

Fosnot

iTrader: (15)

Mine did this out of the blue, so I don't know... There aren't any codes being thrown either, just one side of the engine running really rich (as per the plugs). Start it cold, it idles fine. Then you take it for a spin and get it even slightly warm and it runs like crap at part throttle. WOT it runs fine.


maybe a coil? idk

Fosnot

iTrader: (15)

Turns out it was an Oxygen Sensor, despite no code being thrown. Misfiring like crazy, but running great until it got to temperature.

Owell, gotta love technology right?