Jump to content

Been away for a while, but back - with a problem


PerlNinja
 Share

Recommended Posts

Hi everyone,

 

Been a member for a while but haven't been active for a while, but I'm back. I bring with me a problem... I have a 2002 (yes, really) Pathfinder with Z24 carburated engine in it. You may find my earlier postings about it because honest to god, it's not a typo ;)

 

I've had a slew of engine problems over the past month, from a vacuum leak that stopped a little cylinder extending when the AC came on (so you'd drop right into stall territory), to a carburator that decided to not work right, to idle holding problems, right up to today when the engine started misfiring. If I don't go out much I tend to run the engine from cold to operating temperature on a weekly basis, and that's what I was doing today. My driveway is up a slight incline so generally after a week of sitting still it'll need a start or two before it'll run right.

 

Today was no different, except when it was running there was a very light grey smoke coming out the exhaust, and fluid dripping out - I'm no mechanic but I'd say that's a sure sign of the engine running incredibly rich; that's when the misfiring started, idle revs started shaking up and down, and while it kept on going the vibrations were rather heavy. Taking it up to 1500rpm made the entire car shake and wobble, and there was distinct kind of loping idle sound going on. Sounded rather like a V8 but I'm guessing it's because one cylinder isn't firing.

 

Now, that being said... I'm no mechanic, the nearest shop is over 5 miles away, and I'm in need of some "get this thing going for enough time to make it to said shop". I am, however, a computer geek so some sort of instructions coupled with a "go lookie here on them there internets" will sort me out too. (Please don't suggest getting a Haynes manual, I tried, but can't buy them here, nor can I get them shipped over.. unfortunately :/).

 

 

Link to comment
Share on other sites

Haynes has most manuals in video form available on line. (for a sign up fee of course) and it means running in and out of the house, unless you have a laptop or tablet.

sounds like you have a number of problems all happening at once. if it's running rich there is a temperature sensor issue, one cylinder not firing, can be a host of things, like dead spark plug or just a bad wire.

it could also be a simple thing like a tank of bad gas.

my advice is to approach it one system at a time.

fuel system, electrical, air intake, etc...

do you have access to an OBD2 code reader? that could help you narrow down which system is acting up.

Link to comment
Share on other sites

Hi bushnut, it has no ODB2 sensors at all, it's just a plain old Z24 carburated engine with no bells or whistles beyond what i put in there myself >.>

 

Do you know if there's any pics of the standard carb online anywhere with some reference arrows as to what screw does what? Been trying to find them but.. no joy.

Link to comment
Share on other sites

Took me a minute to find your earlier posts... the Search function here won't show me anything over a year old, which is unhelpful. (Anyone know if this can be reset?)

 

I wouldn't worry about the moisture coming out of the tailpipe unless it smells strongly of antifreeze; often you just get a bit of condensation in the pipe from sitting, and as hot air blows through, some of it turns to steam and some of it drips out. If it was running rich enough to drip gas out the tailpipe, I don't think it would be running (or if it was, the smoke would be black). It does sound like you've got a misfire, though. I'd start by checking the ignition system for a loose wire or moisture in the distributor. I've heard that a crack in the distributor cap can let water in, which can prevent sparks from getting to the plugs. A squirt of WD-40 is supposed to clear it up temporarily, though you should let the fumes dissipate before putting the cap back on. If your weather conditions were right for condensation in the exhaust, I wouldn't be surprised if it formed in the cap as well. The usual fix is a new cap, but a bit of sealant or glue in the crack would probably do the job.

 

None of the US model Pathfinders came carbureted, so info's a little scarce around here. You might try posting a pic of the carb without the air cleaner, on the off chance that it's the same as an older Nissan or Datsun carb, which somebody on here might recognize. Nissan may have raided its older parts bins rather than designing a new carb from scratch.

Link to comment
Share on other sites

Yeah I ran into that search thing myself >.> I'm in a tropical climate; 35 degrees C and 90 to 100% humidity so that'll do the condensation trick I think.

 

I'll take a look at the cap, if that's not it I'll toss the air cleaner out and take some carb pics.

 

Hope I can get this fixed before new years, the timing on this breakdown is horrid :P

Link to comment
Share on other sites

Well, part of the problem's been solved.

 

Turns out one of the spark plug wires came loose, which is really odd considering it's the first time in 3 years, and the car hasn't actually moved from it's place since I last started it and it ran fine. I'm guessing it's been one of my cats, they have this habit of crawling on top of the engine to take a nap when it's raining. Did notice the wires are rather tight so probably going to hit the shop later today and get some new (longer) spark plug wires. The only remaining issue now is that the idle is pretty rough, already mucked about with that to raise it to 750rpm (which IIRC is the "factory default" for this engine), but it tends to dip to 600 regularly, more with the AC running. Guessing it's a vacuum leak since I can hear a rather distinct hissing noise with the hood open, but.. yeah.

 

Anyway, it's drivable again so that solves that! Thanks for the tips at any rate, didn't need them this time but good to know for a next time. At this rate I may just turn into a backyard mechanic after all :D

Link to comment
Share on other sites

I have some 85 USA 720 carb vacumm diagrams I scanned when I did my z24i conversion. Probably similar to yours. 1985 was the last year of carbs in US.

 

http://nissannut.com/projects/z24i_fuel_injection

 

I get emails from all over the world. Apparently they are very helpful. The 85 z24 was extremely complicated vacum lines on my California models. I had my 85 for 10 years.

  • Like 1
Link to comment
Share on other sites

I have some 85 USA 720 carb vacumm diagrams I scanned when I did my z24i conversion. Probably similar to yours. 1985 was the last year of carbs in US.

 

http://nissannut.com/projects/z24i_fuel_injection

 

I get emails from all over the world. Apparently they are very helpful. The 85 z24 was extremely complicated vacum lines on my California models. I had my 85 for 10 years.

 

You're the man!

 

Probably a reason you end up with those emails is that the Z24 carburated engine is still in use in places like Indonesia and Mexico. My pathy (or Terrano as they're called here) is from 2002, I think they used the carbed Z24 up to 2003, after that they're all Z24i's. There's a ridiculous amount of them on the roads here too, the national Terrano club has over 400 members IIRC, with some members having multiple vehicles even.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...