So the other day I unknowingly left the head lights on my car (hid) and the battery died, so I had my neighbor jump start it for me, the car had a strong crank but would not start no matter what, so I brought it to my best friends shop and they tried to diagnose it for the past 2 days, changed fuel pump, cam and crank sensor. Checked all fuses with voltage meter, checked all wiring, injectors and still no start. Car is in great shape not a scratch or ding on it, and I'm so **** about my car I'm at the shop every week maintaining it religiously. Even tried starting it with starter fluid and it started up for 1 second sputtered hard and died. Checked for codes and nothing. Like I said I maintained it religiously the motor was one of the healthiest motor I felt in 4th max. Now I went to the shop earlier today and my friend told me it's the ecu. My nightmare right now is bringing it to the stealership. But if it's the ecu I'd have to bring it there no matter what to get my keys reprogrammed.

My question is if it's the ecu wouldn't it read a code? I'm thinking when my battery died the ecu resetted thus making my keys no longer recognizable by the car.

I'll consider and appreciate all suggestions, please help me fellow maxi brethrens in the mystery of fixing my baby

 

What year is the car? Do you have a chipped key? (immobilizer)

 

Yes it's a 99 manual se

 

Does the red SECURITY light stay ON or BLINK when you try and crank?

 

Cars in the shop but should it blink or stay on if it's a security problem?

 

It should blink.

If it stays solid on, your NATS is acting up. Get your key reprogrammed by a competent locksmith who understands the NATS system.

 

Man these guys are sharp!!!!!!

 

Thx i'll check the security light first thing monday when the shop's open. but if its not what other possibility might it be? my car has spark, fuel, air and compression..

I'll keep this thread updated, and hopefully help out others with the same problem.

EDIT: Could someone tell me if a faulty ecu will throw a code?

 

There is an internal fault DTC (P0605), but I've never seen one actually throw that code.

When the battery died, did you have the keys in the ignition? I've seen quite a few NATS failures in that same scenario, Nissans don't like it when that happens. That being said, the '99s are problematic in the NATS area regardless.

FWIW throwing in a new fuel pump, CKPS (which one? there are two), and CPS != 'diagnosis'.

The security light shouldn't be on at all when the ignition is on, only blinking when the key is off or in accessory. Do you have a second key to try?

 

Nope i did not have the keys in the ignition when the battery died. I had to go to the bathroom really bad so i rushed home parked the car and just ran to the house, afterwards i fell asleep for 3 hours and when i got downstairs i automatically noticed my dash lights was on, and thats when i realized i left my headlights on too. After a few cranks the battery completely died, and thats when i called my neighbor to jump start it. Its so weird because my car was running perfectly right before that. first thing i noticed when i turned the key to ignition was i didnt hear the priming of the fuel pump and that's the main reason i brought it to the shop to replace that. After they replaced it, it still wouldn't turn on but you definitely could hear the new fuel pump priming. One thing i defintely didn't check right is the security light. I'll check that first thing tmr. But my boy is telling me right i have to get a new ECU. but if its thats the case i'll have to bring it to the stealership regardless.

and yes they changed both CKPS all at the cost of the shop because its my best friend shop, he told me it was the fuel pump and his exact words were don't worry if it's not the fuel pump i'll fix your car for free. but even my boy is so stumped because he's been at it for the past 3 days still trouble shooting and hes a certified mechanic for 10 + years.

EDIT: Also my boy was telling if i buy a new ecu it would have to be specifically for my year make and model. and something about some numbers needs to be matching. So i was wondering how true is this? can i just buy any ecu off a 99 plug it up go to the dealership and get it reprogrammed.

My car is a 99 5 speed SE

 

In the highly unlikely event you need a new ecu, you have to source from another 99 manual. Not sure if you have to source for trim level or not

 

No security light guys, any new suggestion

 

Will it consistently run on an alternate fuel source? You mentioned it once in your first post, but didn't get too in-depth.

You mention nothing of any diagnostics involving spark, fuel pressure, timing, etc. Pretty much you listed 'checking wiring and injectors' (how?), checking codes, and replacing a few parts at random.

Easiest first step: check spark (on multiple cylinders, not just one). Second, check for fuel delivery.

Does the shop have a scope? Makes diagnosis much simpler in most areas, especially when you have multiple crank/cam inputs required for starting.

 

Being it ran with starter fluid, you have spark and your ECU is fine.
Your not getting fuel or a pulse for the injectors to fire. (fuse?)

Throwing parts at it is not troubleshooting, I would suggest finding a real mechanic that has a scan tool so you can see which signal your missing.

 

So it did turn out to be the ECU, the shop replaced it and got someone to reprogram the key, and it started right up! Thx everyone for their input much appreciated!