I was driving my Pathfinder and when I tried to accelerate it stalled and stopped. Although I started it again it continue to fail until now that I can not make it start. I do not show any codes and the starter is working. It looks like there is no fuel but I am not sure if there is a fuel pump problem or the injectors are clogged. I verified all the fuses and relays to the pump and they are ok. If the fuel filter is installed reversed, could it lead to this problem? Could the fuel pump be the cause or the spark plugs?

Definitely the first place is to check fuel pressure!

has the fuel filter ever been replaced?

Yes, it was replaced and I am not sure that it was placed in the right direction.

as far as I know theres either a) an arrow or b) it doesnt matter...

Ive done the fuel filter on my Qs a few times before and I never remember an arrow or anything indicating a direction... bottom line is I dont think it matters.

I verified and is not the fuel filter. The fuel pump is working, so could it be the pressure regulator? How can I check it? Do I have to remove the plenum to replace it?

check your fuel pressure first!

I will check the fuel pressure tomorrow and keep you posted on the results.

The fuel pressure is around 42 psi (I believe that is close to the manufacturer spec.). There are no obstructions or problems on the fuel lines. Could it be a ignition problem? Let me know what you think.

ok fuel pressure is golden so its gotta be something electronic. Seems strange that this would start, i agre that it likely has to be an ignition problem..

Can you pull codes and get whatever code is "no fault".... Want to make sure the ECU isnt dead.. Lets put that possibilty on the side for now..

i would try checking for spark. Make sure when you check for spark you ground it against it the plenum..... When you got it to restart once before, did it run really rough?

I checked for spark and don't have any. The time that I made it restart it run nicelly until I stopped at a stop, then it failed during the accelaration and when off. I used my digital code reader and did not recover any codes from the ECM. Please let me know what you believe could be the problem.

Do you get a P0000 code on your reader OR a NO FAULT DETECTED or something along those lines.... What i want to make sure is that the ECU isnt completely dead!

No code detected. The reading is a 0 and NOT P0000.

OK.... i follow you...can you read any of the voltages from the ECU with your code reader... Things like MAF, TPS, etc etc..

If so we need to go through systematically and check every major sensor and make sure everything works.. ASSUMING the ECU isnt fried.

No, I can't read individual sensors with my reader (is a basic OBDII code reader). Would have to use a digital voltimeter for those tests. How can I check the ECM? Which test should I conduct first? What could cause the ECM to fail?

I checked and there is baterry current to the ignition and triggle signal from the ECM. The primary resitance is 0 ohms. The secondary resistance is OK. Do I need to change the distributor? Please advise on alternatives.