Nissan Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1 (Edited)
Hi There.... I'm Joe, and I just joined up here. I probably should have done this a long time ago, as I always seem to find myself here looking for answers.

Anyway, my '96 Pathfinder is not a happy camper right now... here's the deal.

'96 Pathfinder SE
- auto trans
- 210,000 miles
I've owned it for about 10 years, since it had about 40,000 miles... been a good car!

Car was just smogged (emissions test) a month ago and passed with flying colors... car has been running fine up until this incident... it was rather sudden.

My wife was driving the car and said it felt like it was jolting/jerking and then it stalled. She was able to start it again, but couldn't step on the gas too hard or it would stumble badly. She made it home and I took a look at it... I started it and the idle seemed a little off... when it started, it didn't have the nice smooth little rev right after starting, but more of a rough sort of rev. When I stepped on the gas, I immediately felt the stumble/bog... I mashed the gas, and the car just stalled and also did a little pre-igition sounding run on right after it stalled, then nothing. No check engine light was present (yes, the light works).

I started it back up, but it had to crank a little before it started again... and all was still crap.

The next day, I changed out the fuel filter as I had skipped it last service. I started it up, drove it, and all seemed well. Got on the freeway, went a few miles, drove around town a little, and all was good. Went to take it out later, it started up fine, but as I was about to get on the freeway, the stumble came back. Bog and stall as I was just about to merge (yikes). I started it back up and drove slowly in the break down lane... any more than 1/4 throttle and it would stumble/bog/stall. As long as I kept my foot light on the gas, it ran somewhat ok... I got it up to about 60 MPH, it just took a long time to get there.

I got it back home, and it's been sitting since. If I start it up, the same crap happens, then it will run ok for a little while, and then it comes back... and still no check engine light.


Before I start chasing a problem by replacing parts that might be it.... has anyone run into this or know where to look first?


My first thoughts were the fuel system, maybe the pump.... but the car can get up to freeway speed, so there must be available fuel delivery, it's when the throttle goes past about 1/4 way it falls on its face.

I'm also thinking throttle position sensor or mass airflow sensor, but no check engine light.

Any thoughts?
 

·
Moderator
Joined
·
3,553 Posts
I'm leaning toward MAF or coils. Both are common problems.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
It seems to happen hot or cold... I can go start it now, mash the gas, and it'll fart and die.

Wouldn't the MAF sensor or coil(s) spit out a code and a check engine light though?
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
hmmm, that would suck.

If there is no check engine light, there would not be any codes, right? In other words, not worth the effort to take it to Autozone for them to plug a scanner in.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #7
so, it's still broken....

there was a code present for the knock sensor, though I didn't think it would cause the issue I was having, I figured, might as well change it.

WOW, that thing is in a difficult to get to spot!! Had to change the valve cover gaskets, so the intake plenum needed to come off... whats a few more bolts to remove the manifold and get to the knock sensor. Expensive little bugger too... $185 for a part about the size of a lug nut.

Anyway, problem still exists, but at least the valve cover oil leak is fixed.
 

·
Registered
Joined
·
48 Posts
A running issue and no codes present is usually an obvious sign of the computer being bad. Depending on the severity of the valve cover oil leak could be the reason for the knock sensor issue. And just out of curiousity...Have you tried cleaning the MAF sensor? A dirty MAF sensor can cause problems and not set a code.
 

·
My Lil' Red Wagon
Joined
·
163 Posts
my 87 V6 pathy is doing something very similar....ive chased the gremlins up and down with no luck...ive had a fuel pressure guage hooked up and it held a constant 37 psi while missing and stumbling....i have a theory, i think this crappy ethynol gas thats everywhere now is having a bad effect on the injectors...but thats a theory....its almost like i have water in my gas, but i dont...if i fill my tank with good gas and a bottle of heet it will run great for awhile, but if i run it below a 1/4 tank, or fill up in the rain, or at 7-11 the symptoms come back almost immediately....i would suggest pulling and draining your tank, and drain it in a clear container so you can inspect it...since it acted fine for awhile when u changed the filter, it sounds like it did fine untill it sucked some water or something back into the new filter...i hope we can figure this out..
 

·
Registered
Joined
·
1 Posts
I had the exact same problem with my 05 Frontier until I took my MAP sensor out to look at it. Perfectly good, clean as new. Reinstalled it and problem fixed. Intermittent problems are almost always bad connections. I guess those little tiny connector pins are hard to make contact with. I saw on the KN air filter site that most of the bad MAP sensors dealers blamed on the oil from the air filter were perfectly good once they tested them.
Unplug your MAP sensor and replug. I bet your problem will vanish.
 

·
My Lil' Red Wagon
Joined
·
163 Posts
thats EXACTLY what fixed mine!!!! i fought and fought and was about to give up..one day i had it running with the aircleaner off and started wiggling wires...when i came to the MAP sensor i touched the wires and it died....turned out one wire had a bad connection inside the plug, it has been running like a top since!!!!
 
1 - 11 of 11 Posts
Top