Snoopdogie187

Hello everyone.

Car: 92 Nissan Pathfinder XE (4x4), 3.0L V6

The problem is random stalling. Changed the spark plugs and it was fine for a few days. Then changed the fuel filter and then again it was fine for a day again.

It will ideal perfectly sometimes (Getting more rare now) or sometimes it will be lower (400 - 500) and other times it would just barely run (maybe a 100?).

It was miss firing, changed the plugs and it stoped for awhile (it only misfired when it was cold), now it is mis firing again, but also when it is warm at times.

When it goes above 2k rpm it is prefectly fine, might just lack a little power (hard to tell some times with just normal driving).

I can't figure out which cyclender is misfiring. I tried to remove the spark plug wires when it was idealing, but the 3 on the left side made no change it seemed.

It has also idealed high before (1.5k) but that is rare (once a month if that) and stepping on the gas usually brings it down.

It has also (just recently mostly, but a little before) bog down (have no power at all, will barely move) when letting off the clutch in first, then all of a sudden a surge of power.

I'm not too sure what it is and it is confusing me. I have noticed little hoses (they run from the air cleane, egr valve, and a few other places) that aren't in the greatest condition (the one coming off the air cleaner has a big crack in it that lets air in).

Also the egr was repalced about a year ago and that helped the stalling then. It is like we are just getting the outside problems while there is a main one that we didn't find yet.

If any one has any thoughts, please let me know, if you want more information about it, I know most of what has been done to it the last few years (not too much more than what I said here), or anything else about it.

And sorry if I missed anything here, I'm not the one that normally drives it so I don't put up with it everyday.

It also now is pretty much just stalling once you are on the clutch and off the gas. It won't attempt to run, it just goes right down.

I'm also wondering if this can be a problem with either too much or too little fuel or air.

sfoster11254

sounds like a plugged up cataylytic converter

SABL

Hi Snoops!!

Good details.....but....what is the mileage??

Is there a chance that the plugs are being fouled by oil (oil seeping past the valve stem oil seals)??

High idle can be caused by sticking linkage. Could be the high idle detent not releasing.

You may have a MAP sensor that needs replaced...or any other sensor...... too much stuff on today's engines and I have fallen behind the times.

Vacuum hoses can play a big part in poor performance or response. Make sure all hoses are connected and are not cracked. Some vehicles will have the hose routing posted under the hood on a "sticker". I just reviewed your post and it sounds like the problem could be in the vacuum hoses..... I would check them before getting into the sensors. The hoses are cheap but are critical..... you don't want your engine to "suck".

wrench97

Sounds like a vacuum leak on the the left side runners of the intake manifold if the vacuum hoses are in bad shape you need to change them out or cut the ends off to make tight connections which ever is needed, don't overlook the PCV valve hose or the hoses to the power brake unit and heater-A/C controls if they are also vacuum operated.

Snoopdogie187

Hi, ok, I will check into the vacuum lines first, it is just the easiest thing to do.

The mile is like 210,000 - 220,000 (if not more by now).

I don't think the brakes and heater a/c are vacuum operated

I highly doubt oil is getting to the plugs. Ever time I checked the oil for the last year, even right before an oil change, it is perfectly full.

I will also see if I can get any codes from the computer on it, but its not the easiest thing to do it with (It wasn't built with this in mind), It actually doesn't even have a check engine light (only the CA models did).

The only problems it has is the normal ones for this year: the rust, the manifold has at least one broken bolt (big problem with these engines and happens to almost all of them )

Also, putting on new rear shocks (the old ones are shot), following a Haynes manual, but I'm not sure how tight to make the bolts that hold the shocks on (the shocks only have one bolt on each side and it mounts to the frame and to the axel). I'm more wondering if they can be over tightened.

SABL

Hey Snoops!!

The manual should tell you the torque for the shocks.

If you have power brakes they will be vacuum controlled.

Snoopdogie187

All the manual says for installing the shocks is
"Installation is the reverse of the removal procedure. Be sure tat the weight is on the rear wheels before the mounting nuts are tightened."

It is a really simple set up, don't even have to deal with the spings or anything.

wrench97

Tighten them with a 1/2" drive ratchet as tight as you can pull on it if using a torque wrench around 50-60FT LBS will do it.

Snoopdogie187

Thank you everyone for your help.
I have the pathfinder today, so I plan on looking at it and tryingt to test it.

To updat what it does (what it did today).

It has the perefect rpms at ideal when its cold and missfiring. When driving it, until you get it up to about 2.5k rpms it still missfires badly, but it will clear up past that point. If you let off the gas it won't miss fireas much.

When it was idealing again after that, it was pure black smoke. Step on the gas it turns white.

We just put more gas into it (at a quarter of tank or so) because we aren't really trusting the gas that has been in it (when we did the fuel filter, it just didn't smell as gas should).

I also noticed a little leak on the fuel rail (it is just where they used a rubber hose and it meets up with the metal pipe). It isn't a lot, it was only enough to make the spot moist but not drip, and then of course when it is warmer it dries it up.

I am still going to check the vacuum lines today, and the shocks. I'm also going to see if I can get wha ever codes from the computer that I can, if it has any.

Snoopdogie187

Update: I played with the vacuum line(s), only one is really bad enough to cause any problems. I put it in a way so that it should still work at least a little better than what it was. I can't change this yet, have to go buy this piece.

I also ran the codes (just with the ecu self diagnostics test) and the only thing to come up was speed senor, which we just need the speedometer cable really but have to go to the dealer for that (tried one from an auto parts store but the ends are different). That was the only code to come up.

Also, while letting the engine warm up for the test, it started to run perfectly. Ideals at the level it should, step on the clutch, just goes back to ideal, even if you do that at higher rpms.

So either it was the bad line and right now it is just holding in there, or bad gas (which wouldn't surprise me here, gas stations have been caught water the gas down (there is at least one that has been caught a few times) and who knows what else they do.)

wrench97

Black smoke means a rich condition such as an injector leaking or a carb float sticking, does it have fuel injection or a carburetor?

Snoopdogie187

It is fuel injection, but I have taken it for a couple of test drives just before (one was to test how the engine is working, and the other was to test the new shocks). No more black smoke, low rpms, struggling, etc.

wrench97

Sounds like the vacuum leak was the issue then.

Shadowmeph

that has a computer in it? if it does then most likely it is computer related your best bet is to take it to a tec and have them plug into the computer to find out exactly what is going on. I used to work on cars every day and I usually could figure things out just by running it or trying to run it I could usually tell it something like misfiring was caused by spark plug wires or bad plugs and even dirt in the fuel but with this new age of Computers controlling most things on the Vehicle's it is almost impossible to Diagnose the cars so go spend a little money and get a tec to Diagnose then fix it your self. other wise your hitting and missing and end up spending allot of money and time hoping to get lucky

wrench97

They do still have mechanical defects that do not show up on a OBD I system like he has, seeing as he has checked for codes(see Post 10) and only came up with a speed sensor it's most likely a mechanical fault.

Nexxtech

Have you considered your Coolant Temperature Sensor. As mentioned above sounds like its running rich at times. Have you tested your fuel pump pressure?

Snoopdogie187

Well the speed sensor I know why that comes up.
It is a very simple computer, and just running the codes like this would tell me if it is picking anything up I think (the code I get should just be more general then with the tool).

I do have to say it is the vacuum line(s). It is running almost at 100%, with all the power it had, and that is with the quick fix job I did until I can get the hose (just electric tape on the hose to patch it up). The hose was destroyed really, if you look at it, it had a hole in it, and both ends were completely cracked and pretty much falling off. I knew it was a little cracked, but never thought it was this bad.

Nexxtech

As mentioned above if these vacuum lines are universal why not buy them by the foot and replace what you can. They can become collapsed or hardened on the inside. This brings up your PCV valve. Don't think this is your problem though.

I'm not familiar with this Nissan engine completely yet some dealer item vacuum lines may be required. Not sure. I'm thinking a Coolant Temperature Sensor may be pricey for this engine. If not consider this no matter what your codes suggest. In my opinion it takes more than one sensor replacement to correct a combination of error codes. Some are not detected until one is replaced. Does this engine have coil pack ignition or cap and rotor? Let us know.

Snoopdogie187

Yea, going to buy them when I have a chance, a lot is going on. This one line is partly collapsed, I tried to pop it out some for now.

I think its a coil pack ignition but I'm not really sure.