05 No spark, CEL on, New ECM, NEED HELP

[crazysentra]

here is the history.
Bought car from guy who thought timing chain was gone. It ran fine in warm weather(which told me the chain was good), wouldn't start in cold damp weather. Used it for a full summer just fine. Winter, only start after 5-6 tries and would buck like crazy. Now it won't start at all.
CEL is on when key is in on position(therefore I have power to ecm).
Only had spark on 1 cylinder once, then as soon as car would spin over, no spark.
read another post with same issues, they changed ECM and bang, problem solved.
I changed ECM, now I have no spark at all. not even when the engine starts spinning over.
I have changed crank and cam sensors.
fuel pump cuts in.

Questions- do I need to program keys for a new ecm? this was all done in my yard, not at a dealer.

Please don't reply with general stuff as I have tried to narrow this down as much as possible. Trying to get this car on the road as it only has 100k kms and in great shape.
Thanks

[RED_DET]

Yes, the keys must be reprogrammed for the new ecu...

[crazysentra]

how do I know if the car has a security issue? does security light come on with key? does it blink? can someone shed some light on this?

[crazysentra]

security light is on and stays on with key on. doesn't blink. what does this mean? how do I reset if it has disabled the car?

[Gambit X]

have you got the key programmed to the ECU yet?

[crazysentra]

no, waiting to buy software to program the keys myself.

[RED_DET]

You could have NISSAN done this for you by now...

[crazysentra]

The dealership is a 3hr drive from where I live. Not to mention that I don't really have much faith in dealerships for trouble shooting stuff like this as many of the posts in theses forums show. I feel that the research that I have done up to this point probably has me on par with a Nissan mechanic(well close anyway). The car is a 3 vehicle at our house so we don't need it daily.

[crazysentra]

So I programmed the keys, CEL is on when key is on, then blinks after a while. again, I have spark on cylinder 4(drivers side cylinder) only once when you start to crank the engine, then no spark on that cylinder after that. No spark on any other cylinders. Anyone care to give me their 2 cents worth? No codes reading on my obdII either. Does anyone know the sequence of operation of how the engine knows when to fire spark? IE, does it rely totally on the crank and cam sensors? Is timing chain only for the valve timing? where does the ECM fit into the timing?

[Noxy]

Okay, so I know you said not to reply with the basic stuff, but... My car had similar symptoms in that it wouldn't start at all. At first it would take a couple tries and then it would start, but later no matter how much I tried it wouldn't turn over. I tested damn near every electrical connection and I just wasn't getting spark, and this is after I replaced the Cam/Crank sensors. I replace the sensors again with OEM sensors and eventually got it to work. Maybe you got a bad cam/crank sensor?

Also, there is a condenser (capacitor) that sits in the ground wire inline between the coils and the body. If that's faulty the circuit can't be completed. Are you getting power to your coilpacks? Pull a multimeter out and see if you have power at the coils and continuity on the ground wire. Here's a picture of the condenser, sorry I don't have a pic of it installed:

[crazysentra]

thanks for your reply. I am getting power to the coils but not getting the signal from the ecu to fire, if that makes sense. I will have a look for that capacitor and check it out. Hopefully get a chance to work on this car this weekend as I know have it towed to my garage at my house. I have the service manual printed off and should be able to do a good job trouble shooting all the wiring this weekend. I am not sure if the sensors are oem or not but guessing that aren't. the guy I bought it from had them replaced before he sold it. I have done a resistance check on them and they check out fine, although not sure if this is a definite way to check them. I don't have an oscilloscope.

[Noxy]

The condensor should be on the harness that goes under the intake manifold, underneath the tape.

That's exactly how mine was, power but no signal. Unfortunately, I never found out the exact cause of my no-start but what I did was check and clean every electrical connector,fuses, replace cam/crank sensors, etc. Then when I gave up and called a tow to Nissan I decided to give it one more go and she magically started up. Going on about a year now no issues... Knock on wood.

Two random things you might want to look at. First, look at the Cam and crank sensor harnesses, they tend to crack near the plug and you might be losing continuity at one or more pins. All the wires on mine were cracked and I could see copper so I replaced the plug. Secondly, make sure the cylinders aren't flooded. Before I got her to start I took out the plugs and let the cylinders dry.

[crazysentra]

thanks. checked condenser and resistance was good, and continuity of wires was good. Spent 3hrs checking all wiring to and from ecm to relay, coils, cam and crank sensors, etc. All continuity that should be there is there, and all voltages are there when
theyy are supposed to be. only things I haven't checkd are the grounds inside the dash. Not sure how much is involved with this but I think the instrument panel needs to be removed. I also removed the valve cover and had a look at the chain. chain is tight, and is on the marks. The tensioner is out pretty far. I can see 10 notches in the tensioner that are exposed. not sure how much adjustment is left but cant see this preventing spark.

[515moto]

Just wondering if this ever got resolved and how

I have a similar no spark issue with a 04 Sentra.
I was going through all the connections and reset the ECM connectors with the battery connected and I think I fried the ECM. Before I reset the connections I had the SES light when the ignition key is in the on position. Now I have nothing.
If I get a new ECM what is the procedure to reprogram the key? Is the key reprogram required?
Thanks in advance for any suggestions.

I'm getting ready to put a match to the car.

[crazysentra]

what a coincidence. I just got the car running last night and posted the below test on the b15u.com site.
update for anyone who has been following my trouble or may have had the same ones. My actual problem with no spark was that the cam and crank were too far out of sync due to a worn timing chain and the ecu over rides the request for the signal to send spark to the plugs. I have confirmed this by advancing the intake cam that has the sensor on it by jumping out the ivt control valve solenoid. This is normally done when certain conditions of the engine are met and it is advanced for better performance. with this ivt always in the advance position, the engine is still running fine but may lack peak performance. not even sure if it will be noticeable. Essentially, the vvt shortens the useable life of your chain due to the advance it puts on the cam hub. This engines timing is still perfect but the ecu recognizes this condition and does not allow the engine to spark. This would be much more useable if this condition sent a soft fault(one that doesn't disable the engine) instead of the hard fault to not fire. anyway, this may help someone else who has one of these cars. good luck.

anyway, you will need to buy the datascan software online to reprogram the keys. you can just download the program to your laptop and connect to your obd11 port via a usb-obd11 connector(buy those on ebay for 20$). I was told that you would need o reprogram by someone on the other b15u site who seems to know his stuff but never got the car running after I programed the key because the computer wasn't the issue in the first place. I have had the new ecu disconnected 3 or 4 times since and the car still started last night without programming the key. anyway, not sure if this helps or not but if your timing chain is the original issue, you can over ride it by supplying 12v to the ivt solenoid and this will advance your cam shaft to the point where the computer will not over rule the phase difference in the crank and cam sensors.

[turbo691]

Are you just completing the circuit on the ivt plug, or are you running a wire straight from the battery, to one of the two terminals? I have a similar issue, with an 03 spec v, and I feel like I have tried everything. The only difference with mine, is that I get an initial spark trigger, and then it cuts out. I have replaced the cam/crank sensors, ivt solenoid, throttle body, and pedal position sensor. It has power to the coils, 180 psi on all cylinders, and fuel is getting into the cylinders. When I turn the key, the car will sputter for a second and then just crank. The reason I replaced all of those parts, is because I was getting p0123-p0223 codes. Any help would be greatly appreciated. Thanks!