nismo_enthusiast

Hey guys so I have been having an issue with my car (90 hatch 240sx sr20det) after we did some modifications and maintenance to it. I had purchased a new ISIS intake manifold, ISIS t-25 turbo w/ lines to replace the old stock one, New spark plugs gapped to .28, All new gaskets for IACV, Throttle body, Intake + Exhaust sides, fuel filter, O-rings for the injectors, and rebuilt alternator and starter.

Only other mods the car had on it before we did this work were the FMIC, battery, Megan Racing Exhaust manifold and DP, and a Walbro 255. (Worked fine under this set up)

So after we put on the new manifold and turbo it started right up no issues, we noticed on my boost gauge it was over boosting a bit to around 14 or 15 pounds but we later realized that was because we had adjusted the actuator arm on the turbo incorrectly which is fixed now (holds at 9 pounds) but during this whole time the car pulled hard and never misfired or bogged what so ever even running such high boost.

Next day, I wake up and drive it to school, park it, come back 1 hour later and it wont start. Had to get it towed to a friend’s shop where he diagnosed that the o rings didn’t seal for the injectors which cause the cylinder to fill with gas while I was trying to crank and start it. So we got that fixed with new o-rings and running again but now whenever I try and do a pull it misfires and boggs really bad. The car idles fine (950-1050rpm) and even drives fine as in I can take it up to 6k rpm without boost and no misfires what so ever but as soon as I step on it (WOT) or anything more than 5 pounds it starts to misfire like crazy.

We have done a boost leak test and nothing came up, we did a compression test and it read 160 across the board, changed mafs (sr20det maf), changed fuel pump, swapped plugs(bkr7e), swapped igniters, swapped coilpacks, swapped fuel pressure regulator and nothing has solved the problem.
And at this point in time I am extremely stumped on what to try or look at next.

Any input or knowledge or previous similar issues would be awesome


Thanks Zilvia


Shaggy

cotbu

check ecu codes.
What's is the wideband saying during the "bad misfire/bog on WOT"?

__________________

LoverTechnologies "Half Broken Things!"

nismo_enthusiast

no ecu codes present. we even swapped ecu's with another known working one and it didnt change a thing.

I do not have a wideband on my car.

c_mancuyas8

you need to get one that will help to let you know whats really going on. Do you have external coil?

__________________