[AndersonIS300]

I recently got my engine changed due to my last one getting siezed. My new motor I got from JDMofOrlando came with a new ECU, Harness, and etc. but they recommend using the old stuff which we did, so now when we scan my car to see how much fuel I’m getting my car is showing 8 cylinders instead of 6. When I accelerate from a stop my car will sputter at around 2.5k and then it’ll accelerate normally afterwards. I’ve replaced fuel injectors, MAF sensor, spark plugs, ignition coils and wires. What could the issue be?

 

[Falkon45]

Did you swap the USDM wire harness also?

 

[AndersonIS300]

Yeah we used the original harness, ecu, and connected all grounds properly. I called JDMofOrlando and they I have to use my old harness & ECU as well

 

[e_filippo]

Hmmm that certainly is odd. Are you using the ignitor box from the original engine? Is the car stock? How new is your upstream O2 sensor? How did your plus look when you swapped them?

 

[AndersonIS300]

Still using the old igniter, my sparks plugs are maybe a week old and they looked very clean when swapping them, and the only other thing I think it could be are both of my upstream O2 sensors might’ve went bad within a weeks time (not sure how that’s even possible)

 

[Jaysz28]

When was the last time your mass air meter was cleaned?

Also, how is the rubber around the throttle body?

 

[AndersonIS300]

i replaced my MAF sensor with a new one and then it seemed as if my car was misfiring way worse, so I threw my old one back in and it wasn’t as bad. Also I’m putting a different throttle body on Tuesday as well.

im just highly confused on what it could be besides maybe oil getting into the spark plugs from my valve cover gaskets which I’m changing Tuesday as well even though I don’t see any oil residue on them.

 

[Moedean]

Do you have a scan tool that you can graph the live data with? I would check the throttle position sensor while graphing the live data see if there is any glitches or drop outs.

 

[e_filippo]

i replaced my MAF sensor with a new one and then it seemed as if my car was misfiring way worse, so I threw my old one back in and it wasn’t as bad. Also I’m putting a different throttle body on Tuesday as well.

im just highly confused on what it could be besides maybe oil getting into the spark plugs from my valve cover gaskets which I’m changing Tuesday as well even though I don’t see any oil residue on them.

If you didn't do it this way, disconnect your battery for a little while when changing mass air flow sensors. Give the ECU some time to reset, then hook everything up with the new sensor and let the ECU learn the new MAF and see if that helps. It may hesitate for a little bit while it recalibrates all of the sensors, but it will (hopefully) smooth out.

 

[Walter Dembeck]

maybe ur vvti selonoid???? just something to deff check its not hard to get to

 

[AndersonIS300]

I unfortunately don’t, but I had a shop do it and they said everything came out fine besides for the hesitation part. I’m starting to think it’s my fuel pump so I’m gonna try to change it, and if that doesn’t help I’ll be completely lost

it could be, but wouldn’t it throw a code for that or no?

When changing my MAF sensor I had turn battery disconnected and I left it disconnected for about 30mins afterwards since I went to do other things, but after I installed it, it made it seem like there was a huge fuel cut happening