05 Pathfinder Cranks, but won't start

[Portek]

Hello guys,
Thanks that I can be part of this amazing forum.
I have a big problem with my Pathfinder from 2005 with the 4.0 V6. One day I parked my car without any problems and 2 days later it cranks but won't start. I checked it for fault codes but nothing interesting. I had no spark and maybe no pulse, so I checked all fuses, changed the relay for the ECM and changed both cam sensors and the crank sensor (not original because in Dominican Republic it is really difficult to get parts quick). After I changed them, I could start the car one time and it ran like before. After turning it off I couldn't start it again. This worked one time more on the next day and since this day it won't start.

It has no spark and I connected a lamp for seeing the pulse and nothing... I couldn't check the wires directly because I hadn't the wiring diagram for the ECM.
I disconnected the crank sensor to see if it was a failing sensor but no start. But the ECM recognized it. After that I disconnected both cam sensors for same procedure and also no start. But the ECM didn't recognize it. Could this be a hint for a bad ECM?

If I find a wiring diagram of the ECM for checking the cables I will control if there are circuits or breaks.

I measured the disconnected connectors for the cam sensors and could measure 12v on pin 1 and pin 2.

I hope you can understand what I try to explain. My english isn't the best and sorry for that and I hope that we can solve my problem...

[VStar650CL]

You can get the ECM terminal callout on EC-116 here:
https://www.nicoclub.com/service-manual ... 5%2Fec.pdf

See if your scanner shows an RPM reading during cranking. The engine speed on all the older models comes from the crank sensor (CKP), so if you see a nice, steady reading during cranking then chances are the CKP signal is fine. The 12V on two pins is normal when disconnected, one is from power and the other is a from a pullup resistor inside the ECM. However, make sure they all (cam sensors too) read 12V to the third pin and not just to chassis ground. If they read lower (or 0V) to the third pin but 12V to the block or chassis, you have a ground problem. You can find the wiring diagrams for all three sensors in the sections for P0335/P0340/P0345 in the manual above.

[Portek]

Thank you for your help.
I checked 12V and grounds and found out that I accidentaly soldered the connector for bank 2 wrong. Someone changed it, but didn't soldered it and possibly there were connection problems. All wires are good and I cleaned all grounds and the manuals were very helpful.
But when I start the car it won't start perfectly and sometimes it needs more tries... Could this because of the aftermarket sensors? I hadn't time to scan the car after my success.
Before this happened the car started really quick at first try and now it needs some attempts.
I will check for fault codes tomorrow.

[VStar650CL]

Yah, aftermarket sensors can definitely cause issues, particularly the crank sensor. Very often they'll register right at running speeds where the reluctor is spinning fast but get spotty at slower cranking speeds. Nissan ECM's are only good at detecting flatlined sensors, they're very poor at detecting one that's working badly. So the result of an aftermarket sensor which isn't sensitive enough is usually hard starts with no codes.

[Portek]

Ok thank you for this information.
I will buy all 3 sensors OEM and install them when they arrive. But now it runs and this is better than nothing. I hope they last until I have the new ones.

This was really helpful and thanks.

[VStar650CL]

[Portek]

Today it needed many attempts but ran.
Later I checked for fault codes and I have P0021 and when I look into status of the actuator, it shows 34 degree on bank 2 and 9 degrees on bank 1.
Could this fault code caused by the aftermarket sensors or could it be more? I hadn't this code before and this is what irritates me.

[VStar650CL]

Yes, that could definitely be from aftermarket sensors. It would be hard for the engine to even run if those readings were real.

[Portek]

I hope so that this is everything. I love this car and I made so many things and it would be horrible when I have to change the timing chains or at leat the engine because I don't have all tools and the next workshop is one hour away from our home...
Thank you for the information and help. I will report when I have the new sensors or something happens ;-)

[Portek]

Hello everyone,
I will give you some feedback, after getting and installing the original sensors. The car runs pretty fine, starts like before everything started and also the positions of camshaft sensors are perfect.

Thank you so much for the great help!

[VStar650CL]