95 Pathfinder chugging

[Pathfinder1995]

Sputters and has a hard time getting going. Usually if I lift off accelerator it clears for a bit. Can't go over 55 without it sputtering. Terrible on hills. Have replaced distributor cap, O2 sensor and injector that threw a code. My guess it is fuel related, either fuel filter or fuel pump.

Thoughts?

[atraudes]

Definitely start with the fuel filter since it's cheap, pretty easy to replace, and is the most likely suspect. If you still have problems starting after that, try replacing the fuel pressure regulator. When mine was bad I'd have to crank it for a good 5 seconds before it finally struggled to life.

Post back if it's still having chugging problems after you replace the fuel filter!

[Pathfinder1995]

Just changed it with no real improvement. Damn.

Love the truck but no one seems to be able to troubleshoot. Starts fine and runs decent.

Brought to local dealership and all they said is it was running rich and exhaust related. That was a year ago and their reputation is not good.

[atraudes]

That's a bummer My next guess would be the injectors, especially since you had to replace one already and it's still running rich. Here are some things to try to help you narrow down where the problem is.

1. Unplug the vacuum line from the fuel pressure regulator and smell it. If it smells like fuel, replace the regulator.
2. Rent a fuel pressure gauge from a part store and hook it up to the fuel rail. You'll be looking at the pressure when the engine's running, after it's shut off, and how long the pressure is maintained after shutting off. If an injector is leaky, the fuel pressure will drop quickly after the engine's stopped. A bad fuel pressure regulator will also do that, which is why you'll want to rule that out first. Fuel pressure should be maintained for an hour plus. Low pressure while running could also be a sign of a failing fuel pump.

If you end up needing to get new injectors, they can be had on Amazon for about $50 each.

When were the spark plugs last replaced?

[atraudes]

You can also get the injectors flow tested and cleaned if needed for much less. However, you'll probably be without them for a while. I was planning on getting my old ones checked at this place.

[atraudes]

Oh, and try cleaning the MAF sensor. Be sure to buy spray that's specifically made for cleaning, it, though. Other sprays can do more harm than good.