I have a 90 Nissan 240SX with a KA24E motor in it. My problem is that sometimes while driving the car when I hit the gas the car will stall a little and sputter before taking off and other times it will cut off and take about 20 minutes to restart. I've changed the spark plugs, wires, distributor cap, distributor rotor, and the mass air flow sensor. I thought the car would be fine but after just getting gas about 20 minutes ago it wouldn't restart and took a good 15 minutes before it started. Only other thing I know to change is the fuel filter and another friend suggested it could be my timing chain.

Any input on what the problem may be aside from what I've already said will be appreciated.

Thanks

 

fuel pump?

check grounds?

 

In addition to fuel pump check fuel lines. Have you noticed it leaking gas at all? Leaking can me just smelling gas. Sounds like Fuel Pump to me though....check the pump itself and the fuse...although it doesn't seem like it'd work at all if it was the fuse.

 

Check the injectors

 

If I remember correctly your harness got in a fight with your fan a while ago. Even if you think you fixed it i would check over it, and maybe check your ecu.. Cause I know from experience that if the harness is jacked up it'll kill your ecu and maf.

 

maybe u have a leak between the MAF and the TB might want to check that

 

If you can find someone with an amp probe that will tell you if its the fuel pump or not.

If your harness got cut up like Roguewolf240 said that could be your issue as well. Easy way to check is to is to see if there are voltage drops across the wires.

Does your stutter happen right when you start it up completely cold or after it has warmed up?

 

you need to reset timing

 

I am coming in at the end of things. I am not famaliar w/ these engines, but some knowledge might help.....

Does the engine have a Knock Sensor? Are you losing time?

Cold start sensor?

Crank position sensor?

or Cam position sensor?

Check your timing.

If your car cranks up and drives well cold until it hits a point of "warming" up you might have a sensor problem.
If you car starts to get hot and it shuts off/acts up that could be a problem w/ a csv or css. (Cold Start Valve or Cold Start Sensor) if your car cranks right up and goes and starts to crap out after it is warmed up you might be running into different sensor problems.

If it is a fuel pump problem it would be constant. or you would be able to hear the bearings on the fuel pump start to go. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ!!!!!!!! !!!!!!

It might be wiring grounds. But I doubt it.

A leak w/ the MAF and MAF Housing will not cause this. If there was or is a problem w/ this it would be constant. It would be a breach into the intake system and cause more trouble. Even at start up. Maby check your vacuum.

Turn the the key to your car to the "on" position to make sure your pump is working. Yes get a Volt-Meter to check your fuel pump while in operation. What about the fuel pump relay? It could be crapping out too.

If your wiring harness got into a boxing match w/ the fan from the motor I would make sure that the repairs are still good and well insulated

It sounds as if something is getting hot. Why? due to the fact that if your car either cuts off or you cut if off and it is better after 20minutes is saying something. Something is getting reset in your system.

If you want to check your injectors check them w/ your volt-meter first. If it looks good then jerk them out and look at the "spray" they are giving. I highly doubt they will be causing this.


and on a fun note why not check the O2 sensor. Oh wait. You can't until it is hot.


Good Luck.


Start easy then go to the hard stuff.



I now am sure I sound ignorant. If so I really don't care. I am throwing out different stuff for you to look at. If I was near I would help you trouble shoot.

It's a 90. Check your wirig on your knock sensor.

 

that was with my other 240 and everything works fine on that one except it still cuts off sometimes but i'm picking up a MAFS tomarrow.

i see no cracks on any of those hoses between the MAF and throttle body.

i'm still learning and dunno how nor do i have the tools i think

Thank you all for your input. I've changed my fuel filter but it's 4:03am and i don't think my neighbors will like me very much if i started the car up again because it's kinda loud. I'll check the fuel pump after i get my new mafs for my other 240.