1jzchris

So I got a sc4 with a 1jzgte swap over the weekend(traded my stock sc4 for it ). The car rev out freely when in park but once im driving it breaks up, if i hold it at about 25% it will go at about 5lb any more and it starts breaking up and popping.

What i have checked so fa
Spark plugs changed and gaped, no leaks on coils,up plug tps, unplug o2,changed ecu.

Anything else guys?

scmaluco

iTrader: (6)

Have you checked for a loose ground wire or anything?

1jzchris

Yes I did....also just notice that the car is running extremely lean based on how the plugs look. Its stock with a bfm and walbro255.

bodydrager

iTrader: (4)

Have you checked the map sensor? Also is there a CEL?

speed6

iTrader: (1)

knock sensor, since runing lean. my 7m did this. when it gets in boost, it adds more fuel (since no boost id idle). the fuel may not be enough.

INTIMAZY

iTrader: (5)

That kinda sounds like MAP sensor... however, usually when the MAP fails the ECU FLOODS the motor at any hint of positive manifold pressure.

Reset the TPS??

2jzcelica

its your coil packs 1jz and 2jz are notorious for that

1jzchris

the CEL doesn't work,still trying to figure out why. I thought about the map but don't have another one to test. The coils look good as far as I can tell and the car is running lean so I ruled the coil out. Will check the knock sensor

1JZPWRD

iTrader: (59)

Chris sorry to hear about your troubles, this leads me also to believe the coils or ignitor. These are numeraous for the symptoms you are describing. I also could be wrong. I have the same swap in my SC400. Keep us posted on what you find out. There is diy on here to get the check engine light working. GL

1jzchris

[QUOTE=1992Lexus;7263930]Chris sorry to hear about your troubles, this leads me also to believe the coils or ignitor. These are numeraous for the symptoms you are describing. I also could be wrong. I have the same swap in my SC400. Keep us posted on what you find out. There is diy on here to get the check engine light working. GL[/QUOTE


I ruled out the ignitor and the coil,because the car is running lean,if those weren't working it would be running rich because of not enough spark.

g4ebguy90

Boost leak.

1jzchris

had boost leak when i first got the car, but i fix them all yesterday........or so i think.

BenStoked

iTrader: (3)

Have you checked the ecu for blown caps? found one in my brother's 1jz ecu this week, blew out the bottom.

1jzchris

ecu have been checked and replaced. Now I'm thinking its the wiring. I pulled the protective covering off am the harness is a complete mess, loose wires everehere(headaches). Maybe I can just buy a harness and replace this one.

scmaluco

iTrader: (6)

do 1 thing at a time.... try to clean up that harness as much as you can. make sure there are no loose wires/ground. vacum lines to the mapsensor make sure its on there correctly. then keep us posted.. good luck.