3000gt vr4 random power loss

[Fox351]

I have a friend that owns a 3000gt vr4 with walboro 255lph pump with a hotwire kit and 550 cc RC injectors, upgraded stock turbos with a ten mm bore and a bigger compressor wheel, MSD DIS-4 Plus, and borla full exhaust. THIS CAR IS UNTUNED.


With all that out of the way...when we are driving in the car it breaks up under boost and when it gets over 3k RPM which is expected with the lack of a tune. The weird part is when we are just cruising in it at random times it will loose power from only what I can think of as spark because when the power comes back in there is a backfire like it has loaded a cylinder with fuel. It happens so randomly that it seems to be another symptom of the lack of the tune...I thought i would ask the infinite wisdom of IA to see if anyone knows.

[00CelicaGT]

I have a friend that owns a 3000gt vr4 with walboro 255lph pump with a hotwire kit and 550 cc RC injectors, upgraded stock turbos with a ten mm bore and a bigger compressor wheel, MSD DIS-4 Plus, and borla full exhaust. THIS CAR IS UNTUNED.


With all that out of the way...when we are driving in the car it breaks up under boost and when it gets over 3k RPM which is expected with the lack of a tune. The weird part is when we are just cruising in it at random times it will loose power from only what I can think of as spark because when the power comes back in there is a backfire like it has loaded a cylinder with fuel. It happens so randomly that it seems to be another symptom of the lack of the tune...I thought i would ask the infinite wisdom of IA to see if anyone knows.

[seanrg1116]

I have a friend that owns a 3000gt vr4 with walboro 255lph pump with a hotwire kit and 550 cc RC injectors, upgraded stock turbos with a ten mm bore and a bigger compressor wheel, MSD DIS-4 Plus, and borla full exhaust. THIS CAR IS UNTUNED.


With all that out of the way...when we are driving in the car it breaks up under boost and when it gets over 3k RPM which is expected with the lack of a tune. The weird part is when we are just cruising in it at random times it will loose power from only what I can think of as spark because when the power comes back in there is a backfire like it has loaded a cylinder with fuel. It happens so randomly that it seems to be another symptom of the lack of the tune...I thought i would ask the infinite wisdom of IA to see if anyone knows.

FIX THIS AND U WILL FIX UR PROBLEM

[rrutter81]

if your injectors are larger....ur washing the walls of the bore with fuel. Im sure your engine is loving you now.

[SiRed94]

does it even have an A/F Ratio gauge? Tell him to buy a wideband o2, and something to tune and hop on the dyno ASAP...

[alpine_aw11]

Those symptoms sound a lot like bad o2 sensors. That's exactly what my Jeep has been doing, it will lose power and then sounds like it backfires when the power comes back. It isn't mixing the air and fuel appropriately. Change them out and get it tuned, I bet you that's the problem.

[rrutter81]

if his injectors are too large he wont be able to hit stoich even with a good o2 sensor due to overloading the LTFTs

[glimerman]

Are you,or your friend running any kind of fuel controller?
Stock ECU will not compensate for larger injectors on it's own.

[Fox351]

Only a little piggyback. We decided to follow your guys advice and we replaced the oxygen sensors with widebands and A/F gauge got the piggyback and going to get it tuned...who would you guy's recommend to do it?

[ksniperfox]

try any one of the site sponsors....

[glimerman]

Only a little piggyback. We decided to follow your guys advice and we replaced the oxygen sensors with widebands and A/F gauge got the piggyback and going to get it tuned...who would you guy's recommend to do it?

What kind of piggyback?