No spark, won't start. Why?
 

My sister said she drove through about 6" of water then drove it 20 miles and parked it. The next day she went out and it won't start. I messed with it for about an hour today, car turns over fine, it's getting fuel to the rail, but it won't fire. I took a spark plug out and grounded it to see if it would spark but i'm getting nothing.

I checked the fuses I could think of, checked to see if the air filter was wet or anything else was wet and got nothing. I didn't really check any relays because i'm not sure which one would cause this. I assumed that maybe something got wet so we let it sit for a day but nothing has changed.

Anyone have any ideas they want to throw at me before i tow it to a shop?


Edit: Crankshaft Position Sensor maybe???

Take off and clean both crankshaft sensors. And measure the ohms since you have them off.

The water is probably just a conicidence, imo. I've plowed through 8" of water many times (even choking the engine). And 20 miles of driving would dry out any water.

That was my initial thought. But knowing my sister 6" of water could have been 18" of water. I'm just going to make her take it to a shop because i really don't want to mess with it.


I'll have them check the crankshaft sensors before they do anything to it.

Thanks

Good point. Women are lie generators :laugh:

Yea, check crankshaft sensor's also check your engine ground make sure its a clean surface

Also did you pull your plugs? are they fouled out?

I pulled one plug and it looked ok. Hopefully its the crank sensor cuz I don't know what else it would be. I had a crank sensor on a focus that was messes up and it would do this same thing so that makes the most sense.

well the shop can't figure out what's wrong with it. They said it's not getting spark or injector pulse. They are thinking it might be the ECU and are checking prices on a replacement.

I'm not convinced the ecu went out so i might just tow it to my house and mess around with it and try taking parts off my other 03 to see if i can figure it out.

Any other ideas would be appreciated!!

Isn't there a way to check the ecu's pinouts to see if they are working correctly?...

I know you said that you checked fuses but there is a fuse for the ECU that is under the hood by the battery. It is Fuse # 59, 15amp.

http://forums.maxima.org/picture.php...ictureid=28477

Another thought is if the NATS security system burped. The security LED in with the clock would be on. It would keep the car from starting but I'm not sure how. I don't know if it prevents the engine from cranking over or if it kills the spark.

Have tried using a scan tool to pin point the problem?

I'll check the ecu fuse before i have a new ecu put in it. I didn't even think about checking the security system but i could have the shop she has it at check that. Not sure why that would just mess up.

The shop she has it at tried connecting a pretty high dollar snap on scan tool and they're pretty much saying that it won't connect or won't read any codes. So that's why they think it's the ecu.