I have a 1991 3000gt vr4, 117k miles, bought it with a lower end rebuild 500 miles before i bought it.
drove car home after driving, it. eventually got a logger installed, noticed that my rpm seems to go up and down, in idle, during cruise, even in wide open throttle the rpm will drop sometimes before going up. this feels more like a loss of power, than a bucking motion.
It has a slight misfire at idle.
I had found a front o2 sensor harness smashed, but i think i may of mixed up a couple of the wires when i put a new plug on it. front 02 sensor was reading .2v even when full warmed up, and not fluctuating. fixed the 02 sensor wiring, still getting hte same reading, i may of sent 12V heater power, to the sensor ground circuit, never smelled anything smoking but may be damage somwhere, rpm fluctuation existed before i messed witht he o2 sensor and still exists though.
The o2 sensor wouldn't effect warmup or wide open throttle, so i don't think it's the culprit to my rpm fluctuation(rpm goes up and down like 10 times a second constantly)
during warmup, my o2 sensors read lean, then work towards rich, the wiki says they should start rich, and work towards lean before fluctuating back and forth once warmed up. My rear o2 will start fluctuating, but my front o2 just holds a steady voltage.
with car in run, without the engine running, my 02 sensors both read 0.03-0.05v.
I also checked my plug wires, they are bosch, all have continuity, though the resistance is much lower than stock, could these be a problem, the wires themselves are in good condition.but only 600 ohms per foot, instead of like 4500+ ohms per foot of stock wires.
I've got ngk coppers heat range 7 gapped to .028, car has 19t turbos on it, running on wastegate pressure of 11psi.
I'm just not sure where to chase this problem from, don't wanna just start smacking it with the purse, i'll end up parting it if i can't figure out how to fix it. any help appreciated!
I can attach a warmup log if you'd like. actually file size limit is 100kb so i can upload it somewherehttps://datazap.me/u/kruqnut/more-cr...p?log=2&data=8
Oh, also about the car, has vacuum delete, no EGR or Purge at the moment.
Bookmarks