Car is a 1990 S13.
My car gets what I consider good highway mileage (29mpg).
However if I plant my foot in low gears, it spews a cloud of black.
Any ideas why it’s running rich when accelerating but fine when cruising?
Also, is there a spot on the fuel rail to hook up a fuel pressure gauge? I know on older dodges you can just screw the gauge into a port on the rail, but I can’t seem to find one on my car.
I have this exact problem with my talon. Idle, cruising car is clean as hell. Dog it a bit and black smoke screenage.
My problem is that my motor is tired. With 241K on the bottom end the rings are passing some oil under heavier loads. Even though the compression tested great, my leak down numbers were a little high.
If you have a stock KA, no turbo, then I would suspect this or a leaking valve seals/stems as the culprit. A car wont run that rich on a stock ECU so much so that it will show signs of black smoke out the tailpipe. Even with a dead O2 meaning the car will run as rich as possible it shouldnt smoke like that. And if you are getting good mileage that almost certainly rules out the O2.
As for the FP gauge. You can always T into the fuel line and mount a gauge like that rather than tap the rail to install it.
Ya it has 272000km on it, and the compression #'s are 145 - 150 on all 4 cylinders.