Well, my rough starts have turned into no starting at all. I have a 89 Pathfinger v6 that I tried to start 4 days ago when it was 11 degrees outside. There is nothing wrong with the starter but when it did fire I had to keep my foot on the gas for 30-45 seconds so that it wouldn't die, after that it would run fine until it was started again. This continued until today (it's 50 out today) when it wouldn't start at all. I can hear the fuel pump run when the ignition is turned on so I've ruled that out for now.
Has anyone else had a similar problem to this? If so I'd appreciate any help you can offer or even a good place to start looking. If you need any other info please let me know.

Check to make sure your getting good spark. Check your plugs, wires, cap and rotor.

Fuel filter.

Are you buidling pressure at the fuel line? Have some one crank the engine while your under the hood squeezing the fuel line.

Tune-up issue.

Make sure you buy a high quality cap and rotor. On my last tune up I went with expensive plugs& wires but cheap cap and rotor. In this cold weather we have been having the engine misses at start-up.

For your info. A good tune-up consist of cap,rotor,plugs,wires(if there old), air filter, fuel filter. Bosch and BeckArnley are good after market brands. Check on ABCnissan's web site to.

I did a tune up last year with Boscch plugs and BeckArnley ignition components. I've exhausted about all of the "normal" checks and found nothing, so I ended up pulling the computer codes. I get error #13 (Engine Ccoolant Temperature Sensor) and I picked up a new one for about $20.00, I started looking at how to get to the thing to replace it and it seems like I have to take a bunch of stuff off to get to it. Does anyone have any tricks to get to this thing? If this doesn't work I think I'll move on to replacing the IAC Valve next. Thanks for all your help.