Charlie

Don't jump them to the battery, but just jump the two terminals a the plug with a paper clip or a short strand of wire. This tells you if you have a bad cycling switch or not. If it does not click on when you jump the terminals, then you have to back track to see why you aren't getting any power to the coil. Do you have a volt meter? If so, you should have 12 volts at one of the wires going to the cycling switch when the a/c is on.

In that case, unplug the wires from the pressure cycling switch and jump the two pins with a paper clip. It should kick on. If it doesn't click on, then swap the two relays on the passenger inner fender. If the blower motor quits working, then you know you have a bad relay.

Check your cigarette lighter fuse.

-Stock chrome steel wheels -164,xxx -nothing but myself and my school stuff -mostly city, but then again, my commute contains some "country roads" where the speed limit is 55, so technically a mix. Probably 50/50 stop and go and cruising. -no roof rack, no lights, all stock. -vehicle gearing is HG43 -I am calculating my mileage by filling up the tank, resetting the trip odometer, driving until I have about 1/4 tank, and then filling up. I divide the miles driven, by the gallons used, and then multiply by 1.026 to calculate for the 2.6% difference between 235/75r15 and 30x9.50x15 tires. I should probably verify mileage with a GPS but I don't own one. That said, as I was double checking the ignition timing, I noticed that every once and a while, the timing light would not fire, indicating a miss. The truck does not run poorly, and it isn't detectable by feeling the body of the vehicle, so I moved the pickup around to each cylinder, and it did the same thing. I then hooked the pickup to the coil wire, and the same again. Moving to the back of the truck, every time the light showed a miss, I could hear a slight stumble in the exhaust. To me this indicates either a bad coil, or a bad distributor pickup. Watching the tachometer function on my timing light, (again hooked to the coil wire, so really showing RPMx6) the reading would show around 4200, and then every time it missed, would drop down to about 3000. A random miss would definitely contribute to poor mileage, as the extra oxygen in the exhaust stream is picked up by the O2 sensor, and tells the computer to richen the mixture. Any thoughts on this one?

Also, brakes are good, and there is no excessive toe in or toe out. Little bit of negative camber but that's it.

There's now way this thing is getting normal mileage. My old TBI pathy got better than this by a lot. When I said babying it, I'm talking barely accelerating at all, slowly getting to my target speed. Should have been way more than 15mpg. My friend has a wideband O2 sensor for tuning cars, so I think this weekend were going to stick it on and see what the AFR is like. At least that will tell me if it is related to the way the engine is running or something else.

Didn't replace it, but tore it down and inspected it. Looked like it had been recently done, along with a new balancer, so I didn't bother replacing it. If I remember correctly, it was timed right.

I have a 1993 Pathfinder XE 4x4 5spd, 30x9.50 BFG M/Ts. I bought it for $300 knowing it would need work, and have put about $1300 into it so far. I have replaced the O2 sensor, plugs, cap, rotor, wires, air and fuel filter, coolant temperature sensor (both), thermostat, knock sensor, catalytic converter, cleaned the MAF, ohmed and leak tested the injectors, new PCV, fixed the leaky manifolds, and it still only gets 13 mpg. Passed emissions with flying colors, runs great, starts right up, and has plenty of power. I have put three tanks through it now after everything has been replaced. The first one was 12 mpg, which I attributed to lots of idle time while I installed the stereo with the A/C cranked, the second one was 15 mpg babying it, never going above 3k rpm, and not running the A/C, and the third was 13 mpg, driving normally, A/C on in town, with a small 2-3 mile 4x4 trip. I know for a fact that it isn't supposed to be this bad. I had one in high school and I averaged 18 mpg on 31x10.50s with an auto. What am I missing here?

Well, after adding a ground wire to the MAF, fixing the corrosion issues, and the broken wire on the idle switch, and also dumping a can of sea foam in the gas tank, and doing the intake treatment with another can, I've got the thing running like a top. ECM now reads 55, no issues. There are many other issues with the truck, but for now, the engine seems to be running great.

Nope, ECU is good. After a whole lot of probing around with my multi-meter, and performing some tests I should have to begin with...I have found these things: 1. MAF has no ground signal. Known problem, Nissan TSB about it says to add a known good ground. 2. Idle switch, wire broken inside harness, no signal from idle switch reaches ECU 3. Knock Sensor OHM's OK but wire has corrosion at least 1/2" up the wire from the sensor. The sensor itself tests good, but not the wiring. 4. Two of the injectors have the same issue as the knock sensor. Corrosion in the wires, leading to a bad reading and not the actual injectors themselves. Looks like that covers all the bases. I can get pictures when I have time, and will also post as to whether or not this actually cured the problems. I just have a bunch of work cut out for me putting it all back together lol. As for your problem Nissan, I would simply add the ground at the MAF and see if it cures the issues. It just might.

Negative ghostrider. I still have to do that. No time this week lol. Finals and all.

More and more on this one, I'm, leaning towards a bad ECU. I rewired the fusible links, pulled intake and ohmed the knock sensor, pulled the front cover and checked the cam timing, all looks to be good.

Looking at ordering a full carpet kit from stockinteriors.com. Does anybody have any experience with the fit and finish of these kits? I installed a kit from them in my 93 Dodge Power Ram and it fit OK. Just wondering if anybody here has any direct experience with them. Also, Looking at ordering a dash cover like this one: Ebay Dash Cover I have heard that some don't quite fit right or look like crap. If anybody here has any experience with them, it would be greatly appreciated.

Mine is multi-port. The fusible links are the smaller wires that come off of the positive battery post.

So...After countless hours pouring over the FSM and my Chilton's, I have discovered something rather interesting. The MAF and the injectors get their power from the fusible links at the + battery terminal. Turns out, the fusible link for the Injectors is completely burnt/missing on my Pathy. Hmm, makes me wonder how it ran at all. Anywho, I am going to replace the fusible links with a fuse box just like I had to do on my Dodge, and see if that helps. I will keep you all updated. If the Injectors wern't getting any power, than that would easily explain why all the codes are being thrown. The MAF codes, because the Injector duty is way off compared to how much air is coming in, the Injector codes because obviously the injectors are not being powered correctly, and the other two...who knows for now. The important thing is that I may have just jumped a rather large hurdle.

Ok, I haven't logged on here in at least a few years. I used to have a really clean '88, but it got totalled by a red-light runner. Long story short, I just picked up a '93 5spd XE for $300 knowing I would have to put some money into it. It sat for 18 months before I got it due to an oil leak, but started with a jump, and drove onto my trailer under its own power. It idles fine, but starts rather slow, and if you give it any throttle, it stumbles and blows black smoke out of the exhaust as it is running pig rich. After pulling the codes, I have the exact same 5 codes you do. 23, 45, 12, 34, and 51. I have already pulled the injectors, re-sealed all of them, and ohm-ed them out. They are all good. If I find anything else, I will post up A.S.A.P. It has to be a similar issue to yours. I have already cleaned the MAF sensor, and done a compression check. I have very low compression on one cylinder, and it is leaking past the intake valve. I believe it to either be stuck, or bent. I am going to Seafoam the crap out of it to see if it will un-stick the valve, but have already ordered a full gasket kit in the event I have to tear the motor down.

I have a hydrogen fuel cell in a 1994 Chevy Cavalier that I am currently working on to be a daily driver. So far I have only been able to get a best of about a 3-5 mpg difference. I have also had my scantool connected to the car and there is a difference in the injector pulse widths when the hydrogen is being pumped into the motor, but it is not a great difference. This is because you would have to have a fairly large fuel cell to produce enough hydrogen and pressure for the car to run on hydrogen only. How ever, it seems that carbed vehicles work a lot better than EFI because you can manually lean out the motor instead of relying on the computer to do it. My coworker has a Geo with the old carbureted motor and he is getting 70+ mpg with it and he has a small fuel cell in it.

Unplug your maf sensor and check for corrosion on the pins. I had this same exact problem on my 89 and could not figure it out for the life of me. I leaned on the wiring harness and it died. Thats the only reason I found it. Make sure all the connections are clean and secure.

OK, I had the air cleaner off with the motor running yesterday trying to figure out what my problem was and I leaned on the wiring harness and the truck stumbled and died. I pulled the connector off of the maf sensor only to find that the maf has copper pins, and the connector has steel pins and it was all corroded inside. What dumb mother-f*&$%# thought of that? Thats the whole principle of electrolysis. Two dissimilar metals and an electrical charge. As soon as the connector gets wet, it corrodes.

bump

no water in the dizzy, and on the way home tonight, the engine light came on. I checked the codes and came up with a code 32 for EGR function. hm.... gonna have to check that out tomorow.

I went romping this weekend and went through a few big mud holes. Afterwards, my pathfinder seems to be missing like crazy. under any kind of acceleration under 4000rpm it bucks and shakes and barely moves. I checked the trouble codes and it shows 55. (no problems) I thought it was just because something got wet, but It has been 4 days in arizona and about 300 miles and it still misses. I would think everything would be dry by now. I put a bottle of Lucas in the tank, pulled the throttlebody and cleaned it, cleaned the MAF being careful not to damage the wires, and made sure all my spark plug wires were connected properly. the plugs, wires, cap and rotor have about 2500 miles on them, as I replaced them when I got the truck. If I am missing anything obvious, please let me know. I have read all the stickies, and used the search function a million times and still, I have nothing. I am hoping that someone on here can help me. Heres a pic from the romping for your enjoyment:

replace the fuses for the accessories in question, even if they look fine, they could still be bad. I've seen that lots of times.

I have an aluminum Howe radiator in the truck now, that i stole from my project car cause the pathy one gave up the ghost. I have the entire 1998 Chevy 1/2 ton truck complete with wiring harness, computer, fuel system etc. as for the condition of the motor, it was rebuilt about 30,000 miles ago, along with the tranny, and was my shops parts runner for a long time, It has been regularly maintained and well taken care of, I would have no issues with questioning the condition of the motor. As stated, I work in a shop, have all the tools and equipment necessary I seriously think I could pull it off with two full days in the shop. As for the air intake, I will probably just run a cone filter over the OE inlet tube.

Ok, well, I haven't spent any money yet, as the motor was free because it came out of a totaled company truck, How easy is it to swap the later VG30E into the 87? They go for about 400-500 for a 30k-50k motor around here. Is it a matter of bolting it to the stock transmission and obtaining a new computer, do I need the VG30e trans to go with it? I could get the whole bundle for about 800 through work probably. what about the VG30DE?