I have a 1991 Nissan pathfinder SE 4 wheel drive v6 with 175000 miles on it that i just purchased a couple weeks ago OK to start things off i washed the motor and some how knocked a vacuum line off the motor was running rough and sputtering i didn't see the vacuum line off so i changed all spark plugs distributor cap and rotor thinking that was the problem but it was still running rough as in sputtering and running very rich well i found that the vacuum line was off reattached it and it ran better but was still sputtering when you let off the gas and the idle was still rough i would have to kinda hold the gas and the brake at red lights well tonight i went to the gas station to put fuel in it stopped it went in paid for my gas pumped it and got in the truck tried to start it it turns over and will not start i pulled the fuel filter off and blew through it no blockage, it had pressure on it so it seems the fuel pump is working, i pulled a spark plug wire off and used a screwdriver so see if it was getting spark and was i checked all fuses in the card and they are fine. i tried pumping the pedal while starting it holding it to the floor and still nothing. you can smell the fuel and it has spark so I even disconnected the battery and reset the computer i have no check engine light that i have seen on the dash at all so i am really lost if anyone could help me i would greatly appreciate it!!!
Sounds like the mass airflow sensor needs to be reset. Disconnect the battery first. Disconnect the electrical connector on the mass airflow sensor and wait about 2 minutes. Reconnect the mass air flow sensor. Finally, reconnect the battery. The mass airflow sensor is an electronic device that reads or tells how much the gas: air ratio is to fire in the chambers/pistons. After the vacuum line became disconnected, it probably threwthe information off and started running rough.