Quote:
Originally Posted by Nikzilla
UPDATE:
So I tried to pressurize it, and I couldn't get more than 5 psi with a bike pump. Once I pull the pump off, the pressure veeery slowly goes back down to 0 on the gauge, but if I pull a vacuum hose there is still a lot of gas velocity.
So I hooked up my DIY smoke machine (electric air pump > paint can with rag in it > PVC). Lit the rag on fire, let it burn for ~30 sec, turned on the air pump, and put the lid on. The air pump couldn't get more than 3 psi, but I couldn't find where the smoke was coming out. All I could see was very very very light misting around the turbo, so light that I think I was imagining it. I'm thinking of taking it to a shop to have em run a real smoke machine through it, not sure if they will be SR friendly thou.
In terms of wiring, there is no extension! The O2 plug runs straight into the harness after 2 inches. There is however a clamp on the middle wire that goes to the narrowband under the dash that the previous owner installed. It doesn't work thou cuz I accidentally snapped the wire while doing my gauges. I unplugged the sensor clamp just now though just in case it's accidentally grounding it on the exposed end.
|
See if you can get a better picture uploaded that I can look at. For now, Ill just throw some ideas your way.
You say the injector duty/maf/tps do not move when the problem occurs. Only the oxygen sensors report a problem. You never answered whether you can feel the engine hesitate or if you can notice that the engine runs differently when it happens?
IF the ECU is not changing any values, but the fueling suddenly changes, something in the fuel system may be causing it. Possibilities are, fuel pump, fuel filter, fuel regulator to name a few. Since you are cruising, and the problem corrects with throttle, the fuel pump is unlikely. If vacuum at the regulator was the issue your wideband would show us a rich condition, not lean. I am still not sure if the engine is flipping out of closed loop, you said the fuel trim sits still. Does the fuel trim normally move while driving? I am unfamiliar with that data tool you are using.
If the fuel isnt changing, that is, if the injectors dont change, and the fuel pressure doesnt change, then the engine cannot suddenly go lean with no reason. Unless the ignition timing is suddenly going really wrong, or getting really weak, such as if you retard the timing 20-25*, THEN you would get a nice fat lean reading suddenly on your wideband, and the engine would lose significant power, and require more throttle position (ive asked already now twice if this happens you never answered). If the car continues driving normal-like, with the same throttle position etc... then we look elsewhere. Also check the ground for the coil packs at the back of the head. And look at your plugs, change them if they are very old or dirty.