Stock KA24DE carbon spitting from tailpipe

[imMrDude]

I have a '93 240sx, only modification is an after market air intake.

There are a few notable issues I would like some advice on.

Weeks ago she was running on three cylinders, I had an injector replaced and all was well. But, since that was done she hasn't been firing up with only the key. I need to use the gas pedal to start the engine whenever the engine is cold, when warm it starts right up. The fuel filter was somwhat clogged so i replaced that to no resolve. At times the engine is actually flooded so I need to put my foot to the floor to start it. Leaky injector?

I have had water, and chunks of carbon spitting out of the tailpipe. There is no coolant in the water so I don't think I have blown any seals. Also, the cat is brand new, replaced a month or two ago so I could pass smog. Makes me think that the engine is running too rich.

Lastly, there have been two instances of the car overheating. This is what is strange to me. The first time I lost some water through a loose hose next to the intake manifold but I don't think I lost enough to make the car overheat, the second time I didn't lose any water. But, both times I lost some oil. In the second instance, I had almost a half quart too much oil when I left, and almost a half quart too little oil three miles later when I pulled over. So I added half a quart and drove home. When I checked the oil the next morning, I was a half quart over again. Should I drain out the excess?

Thank you.

[davidoliva]

I would reccomend performing a leak down test, this will help locate the problem. If you hear air leaking out the intake, its your intake valves, if its coming out your exhaust, its your exhaust valves, dip stick tube then its your rings, etc...

[moso]

You most likely have a leaking injector causing the fuel to flood the cyl before startup. It could also be causing the car to run rich, IE black soot out the tail pipe. The water is likely condensation, you would be seeing white smoke if you blew a gasket enough to get coolant out the tailpipe. If your KA is overheating I would check the system for air bubbles, jack the nose of the car as high off the ground as you can get it, and I mean way up there!! then run the motor until the thermostat opens, look for flowing coolant in the radiator, then top it off. You shouldnt be seeing a change in the oil levels in the motor, there is nowhere for it to "hide", chances are you just didnt get it checked quite right, I wouldnt leave excessive oil in my motor, it has been known to cause some strange problems.