Jump to content

krmiller07

Members
  • Posts

    289
  • Joined

  • Last visited

  • Days Won

    1

Posts posted by krmiller07

  1. Does anyone have any suggestions on lossening the power steering pump as so you can remove the belt? I have lossened the adjusting bolt on the bottom and was able to loosen the top right bolt ( facing the front of the vehicle) are there more bolts to loosen, hidden some where ?

  2. Yup, that screw adjusts the idle when the A/C is on. The FSM doesn't mention anything about it adjusting the idle mixture. That'll be controlled thru the ECM based on sensor inputs. Have you checked your vac hoses yet?

     

     

    Yes, I've performed all of the "common sense" diagnostic's and haven't seen any codes show up on the ECU. I'm obviously stummped ! Motor has about 45,000 miles on it with good compression and minimal leak down.

     

    Thanks

  3. untill completley warmed up the tbi retards timing 5 deg and enrichens the fuel.

    Idle mixture is set byt the MAF & ecu.

    once the engine is warm check your timimng, 15* should get you some help, stock is 12~13

     

    then run ecu diagnostics and see what codes you get(guide is in the how to)

    It wouldn't hurt pour a bottle of gummout regain in your tank. might clean up an injector issue or gunked valves.

     

    Thanks,

     

    I have my timing set @ 15* at operating temp, and I've just recently cleaned my MAF by taking it out of the TB and carefully cleaning it with denatured alchol and a clean q-tip. all of this helped a bit, but I don't remember it ever idleing this rough then warm or on start up. I'run all of the injector cleaners, seafoam, techron etc..

  4. I have an 89 Pathy with the 5 speed. My question is, have any one had any issues or experince with adjusting the idle mixture on the engines ( V-6 ). My truck idles a little rough, or rich on start up, sounds like a carbed motor with the choke partly closed ! I'm getting piss poor gas milage both on the hiway and in town. It still smells rich even when the temp comes up to operating temp and idles kind of rough even though I have new cap, rotor, wires and plugs.I run a factory type K&N air filter, and have no Cat converter. The ECU doesn't pull any codes, and I replaced the 02 sensor with a new Bosch unit about 1500 miles ago. I'm running out of ideas. Someone told me theres a larger (slotted) screw on the passenger side of the TB that adjust the idle mixture and to some degree the "fast idle" speed, when the A/C or fan is running. This screw is normally covered or plugged from the factory for emissions reasons. Mine is not covered. and moves freely.

    has anyone encountered this issue or have any suggestions on this topic ?

     

    Thanks,

     

    krmiller07

  5. Does anyone know if there is a 'return spring' that put's tension on the rear parking brake cables, to help them return from the engaged or 'Parked' position. One or both of my rear calipers or brakes seems to stick, after I've realesed the parking brake. I can feel it drag for a few blocks before it releases. I crawled under the truck, but didn't see anything obvious aside from the possibility that the rear cables to each caliper may be rusty or dry inside and not releasing the brake shoes in the rotors.

     

    Thanks,

     

    krmiller07

  6. They have it backwards. The system runs in open loop with preset values until the motor reaches operating temp, then it goes into closed loop. In closed loop it monitors all the sensors to give you the correct fuel mixture. Everything must be in good order to function properly, even a loose or coroded ground could cause problems.

    I wish these trucks would be like the newer OBDII system that can give you live data. That way you could look at the sensor values to see if they are working properly. The only way to check these sensors is to back probe them but you must know what values they are supost to run at.

    First you must make sure your ignition system is in good shape then go to the emission system. With the limited data the computer gives us to trouble shoot I really wish someone made a replacement intake and carburetor setup.

    James

     

    Here is the email and info he sent me. I wish I knew about this option last year, I had to scare up a used Throttle Body from a salvage yard in Arkansas so I could rob the injectors from it.Used cost me $400.00, but New from Nissan was over $700.00. Just for the injectors !

     

    Hi Keith. Thanks for the questions and sorry it has taken so long to get back to you.

     

    We are able to modify the TBI equipped VG30 intake manifolds to accept a 350 or 500cfm Holley 2bbl.

     

    http://datsun510.com/photopost/showphoto.php?photo=10226

     

    That’s the easy part. The challenge right now is the ignition because the VG30 distributor with vacuum advance for carbed applications is currently NLA from Nissan…

     

     

     

    What I heard long ago was that The NLA Nismo/Saudi truck distributor is apparently available again through Nissan Motorsports.

     

    1-866-754-5500 p/n M-22100-V6402 14-21 day delivery - $292.10 USA - ask for Russell internet sales.

     

    But I have yet to have anyone confirm that they were indeed able to get one.

     

    www.nissanparts.cc lists them as well.

     

     

     

    In lieu of the cool distributor, others have made their own ignition systems:

     

    Option 1) I have is reports of at least one customer taking the guts out of a 240/260/280z car distributor and somehow grafting them into the VG30 distributor.

     

    Option 2) recommended by Dave (the guy who builds the VG30 install kits) is to use an Electromotive DFI system.

     

    Option 3) some short track racing series called “pro-6” used the stock Z31 distributor with a Crane Hi-6 ignition box.

     

    Option 4) a guy named Mike Guido (with a VG30 powered mini) mounted a magnetic pickup through the side of the stock distributor and has an MSD digital 6 control for it.

     

    Option 5) mega-spark (look up mega-squirt on google)

     

     

     

    There are probably other options as well, but that is what I have for you.

     

     

     

    --carter

  7. They have it backwards. The system runs in open loop with preset values until the motor reaches operating temp, then it goes into closed loop. In closed loop it monitors all the sensors to give you the correct fuel mixture. Everything must be in good order to function properly, even a loose or coroded ground could cause problems.

    I wish these trucks would be like the newer OBDII system that can give you live data. That way you could look at the sensor values to see if they are working properly. The only way to check these sensors is to back probe them but you must know what values they are supost to run at.

    First you must make sure your ignition system is in good shape then go to the emission system. With the limited data the computer gives us to trouble shoot I really wish someone made a replacement intake and carburetor setup.

    James

     

    Thanks James,

     

    Actually I did find a company that will and can modify the stock intake to accept a small 2 barrel carb. Apperently these are very popular with the people that race the older Datsun 510's with a V-6 upgrade. The only problem I understand, is you also have to change the distributor and McGyver a way to properly hook up your throttle cable. I have no idea how comlicated it could get with all the other wiring thats part of the TBI ? There are some posts on a site dedicated to the VG-30.

    I'll dig around and see if I can provide the links or sites. I think this is on of them : http://vgpowered.informe.com/index.php

  8. The FSM for my 87 says:

    Warm engine

    turn diagnostic switch "on"

    after lamps flash 3 times, turn switch "off"

    read flashes

     

    Here's the note I think you're interested in:

    Caution - During displaying code # in self-diagnostic (mode 3) if another diagnostic mode should be done, make sure to write down the malfunctioning code # before turning diagnostic selector "on", or select the diagnostic mode after turning the ignition switch "off". Otherwise self-diagnostic information stored in the ECU memory will be lost.

     

    The stored codes should clear once you turn the mode selector switch back to the "on" position w/o turning the ignition key off.

     

    The FSM also says:

    codes stored in Mode 3 diagnostics will automatically be cleared once the starter is activated 50 times. If the item which has beed judged to be malfunctioning and stored in memory is again judged to be malfunctioning before the starter is operated fifty times, the second result will replace the previous one. It will be stored until the starter is operated fifty times more.

     

    Basically, the code will clear once you start your truck fifty times. If the code pops up again, it'll take another fifty times w/ no problem to clear.

     

    Are you sure you have the right O2 sensor and is the lack of a CAT throwing off the emission system?

    Thanks, Yes I have the correct O2 sensor, they come with 2 plugs attached to a 'pig tail' running up from the sensor. As far as the 'Cat', well the O2 sensor is upstream from the CAT by a fair amount. Someone else responded to a previous posting I put on here, regarding the very poor gas mileage I have been getting, they claimed that the O2 sensor really only functions during warm up, or until the engine or coolant reach a pre-determined tempature ( 160-170*F) then it goes from a 'closed loop' system, to an 'open loop' system. My uderstanding of this is, once the engines at operating temp, the O2 sensor reall doen't monitor the exhaust or send a signal to the ECU, calling for mixture changes or adjustments. Is this the case ?

    I owned one of these trucks when they came out in 87. I bought one brand new, with an Automatic Trans, ans I don't remember the mileage being this bad. It wasn't great, but it avg. more than 8-10 MPG on the hiway.

    I'm open to all ideas !

     

    Thanks again,

     

    krmiller07

  9. Does anyone have the proper method or at least a successful method of erasing the codes or resetting the ECU on the 3.0L Pathy? I have just replaced the O2 sensor on my truck with a Bosch factory replacement unit. I have read on here, that some people have simply disconnected the battery for as long as 12 hours. The local dealer says this isn't the proper method, and would be happy to reset it for $90.00 hr, 1 hour min ! He also said you need to change the 'head temp sensor' or coolant sensor as the work in unison at keeping the TBI working properly and keeping fuel mileage in line.

    I had a posted on here about a week ago, in regards to the very poor fuel mileage I get both in town and on the Hi way. The motor is stock, with about 40k miles on it. The only changes are: K&N air filter, Warn Hubs and no Cat ( Bought it this way ). Aside from that, the engine runs very good and seems to make pretty good power, idles smooth with no backfires or 'popping' either stationary or decelerating. It even blows 'smoke rings' out the tail pipe idling !

     

    Thanks for the suggestions in advance : ).

  10. Does your sensors connection mount on the top of the passengers side fender ? BTW- what year and version of the V6 do you have and is it a 5 speed or AT ? The other question that comes to mind is. Since it's my undersatnding the the memory in these ECU's are ROM ( Read Only Memory ), would you, or do you diconnect the battery every time you disconnect your O2 sensor, as so the ECU 're-learns' it's new operating parameters. I've read alot of posts on here with regards to emissions as well as the TBI's and the one thing that remains fairly consistant, is every one disconnects the battery for at least 12 hours, before running the engine. Apparently, this helps the computer to learn the 'New' readings ?

  11. This might be part of your problem. These engines are designed to run on 87 octane. Higher octane fuel burns slower, so not all of your fuel will be getting used.

     

    If you want the "cleaning additives" that the octane booster supposedly gives just fill up with name brand gas like Chevron or the like.

    Thanks, but I don't think it's the octane booster ! The idea behind higher octane and a 'slower' burn is to increase the amount of energy per cumbustion cycle. It dosen't effect any 'left over fuel' in the cumbustion cycle, that would fall under a poor general state of tune within the engine it self.

    Thanks though.

  12. A tail spin? Not likely, there would be some safe mode pre-set fuel map - which would likely be conservative (rich) to avoid a dangerous lean condition.

     

    If you are getting 400-450km in a long trip but crappy mileage in a short trip, the truck may taking too long to warm up. I snagged the following from a different thread where I was helping someone who thought they were revving high on the highway...

     

    When you first start your truck (cold) the engine operates in "open loop mode" This bypasses readings from the O2 sensor and the engine runs rich to help it warm up. During this time the automatic transmission's lock-up torque convertor will not lock up. This causes higher RPMs. Once the engine reaches the correct operating temperature the O2 sensors come on line and lean out the mixture and the torque convertor locks up which drops the RPM a bit (feeling like a shift into OD). This allows the engine to warm up and the truck to go down the road in the best manner possible until things are warmed up.

     

    If the warm up period is taking longer than it used to, it could be:

    Very cold outside

    Thermostat stuck partially open (most common in my experience) or incorrect thermostat

    engine temperature sensor malfunction

     

     

    Some O2 sensors also have a heater circuit in them.... My pre-96 vehicles did not, I am not sure about the early pathys. This is another failure mode that can use fuel on short trips.

    Thanks, but the truck is a 5speed and I religiously allow it to warm up for at least 5- mins or until I see the temp gauge starting to rise. I have checked to see that all the 'cold start' equipment is funtioning properly, and it is. Do you have any input on targeting the O2 sensor, besides going off the code from the ECU ? I'm at a loss here !

     

    Thanks again. : ).

  13. Adam, you can advance the timing on the TBIs to 15 degrees from the factory 12 and usually get better gas mileage.

     

    Does the exhaust smell rich at all? Also, maybe disconnect the O2 sensor and run it on the highway and see if your mileage increases. My O2 sensor was bad, and I got almost 2 MPG better on the highway than with it connected.

    I love your window sticker BTW ! :aok: It only smells rich during warm up( Normal ) but after it reaches operating temp. It smells normal ( I think ). I don't know if you can adjust anything on the TBI except cold ( Fast ) and normal idle speeds. All I know is that I would think I should be able to drive more than 30 miles with out burning through 1/4 tank of gas !?. BTW, wouldn't diconnecting the O2 sensor throw off the ECU and send it into a tail spin ?

  14. I'd replace the O2sensor, running rich or having other contaminants in the exhaust system will ruin them fairly quickly.

     

    Have you checked the computer for codes?

     

    The mechanic I've talked to, have said you can get 'false positives' from this type of ECU, and that those code only point you in the possible or general direction in regards to faulty components ? A new O-2 sensor runs about $ 150-180.00 from Napa ( Bosch ) and once they've been installed, you cant return them. I don't really wnt to throw money at it and hope it improves, I'm trying to pinpoint and replace as necessary.

  15. I'll assume you are running at least a 180 stat.

     

    If everything is working so great, perhaps you are getting better mileage that you realize. How many kilometers per tank do you get? Have you verified your odometer is accurate?

     

    Is this a carb or FI?

     

    I am running a stock Thermostat, and I average around 250-280 miles per tank on the hiway. However the last few weeks, I drive about 30-35 miles and burn through approx 5-6 gals or 1/4 tank of fuel. I verified this when I top off at the pump. In addition this truck has TBI ot Throttle Body Injection, Or 'Electro-Injection' as it referred to on the air cleaner cover. I have never had the odometer verified, but it seems to be working just fine.

  16. Yes, it has a new thermostat and it runs normal and make good power through all RPM's, no backfiring, steady smooth idle, rev's evenly and doesn't 'race' or fast idle. What about the MAF sensor ? I read an entry some where on hear about someone taking theirs off the side of the throttle body and cleaning the wire with isopril alcohol or MAF cleaner.? The only thing I regularly do, is pour a bottle of '107' octane booster in before every other fill up. This seems to make somewhat of a differnce in throttle response and smooths out the idle while waiting in traffic or standing still.

  17. Since I read your responses to this topic. It got me thinking, I have an 89 Pathy and I replaced the engine with a lower mileage VG-30 with about 40K miles on it. I did a compression and leak down test before installing it, and every thing was in check. However my hi way mileage averages about 6-8 MPG which is horrible. The cat was removed when I bought it, and since the state I live in has no emissions checks, I have left it that way. The AIR pump is still in place with the belt, but the pipe to the exhaust has been capped off. I just did a complete tune up. Plugs, wires, cap and rotor. Checked and replaced all the vacuum lines etc. The truck runs and idles great. In fact, I just had the exhaust manifold gaskets form the 'Y' pipe replaced due to a leak, and the mechanic said it ran really good and strong.( he was impressed )! My timing is set at 15* BTDC.

    But the mileage is awful. I even put Warn manual lock out hubs on it, just for the peace of mind in knowing they are disengaged. Someone suggested i replace the O-2 sensor, since it's the original one, and the stock motor literally blew a rod while tooling down the freeway. The guy said it's possible the sensor was contaminated from years of running rich and possible coolant leaks from the old cracked heads I found when doing the engine swap. ( I swapped heads, before doing the entire engine swap ) the exhaust pipe looks so clean, it actually looks like rust is forming at the end.

    Does anyone have any ideas or feedback on the O2 theory or any experience with improving the mileage. This is my second pathy, and I know they aren't know for their mileage, but I should be getting better that what I am, especially on the Hi way !

     

    Thanks.

  18. Ok, I know this is going to sound ignorant, but I am trying to determine and find the factory, as well as any suggested ingition time specs, for the VG-30 V6. I have tried the Nissan dealers ( their computers on go back to 94) as well as thw local national auto perts stores. My haynes manual says to refer to the emissions sticker under the hood, which would be fine...if the hood was off of a V-6 !

    I discovered the distributor bolt was left loose, from the last shop that did a 'tune up'. I'd like to get a baseline setting or adjust it for maximum milage and or power, or a balance of the two.

     

    Thanks,

     

    krmiller70@hotmail.comKeith

  19. Hi,

    I am trying to locate the 'correct' ignition timing spec's for an 89 Pathy. VG-30/V6. I have a Haynes manual and it refers you to the emissions sticker on the underside of the hood. This would be fine, if my trucks hood wasn't off of a 4 cyl. truck ! I've checked the posts on hear, Nissan dealers ( Only can go back to 1994) on their computers!, auto parts stores ( Auto Zone, NAPA and O'Reilly's etc... No one seems to know how many degree's or the normal procedure.

    Also I would appreciate it any one has a 'preferred' setting in degrees. My engine was replaced a year ago, it pings under load, and when I put a timing light on it, it was 2" off the crank markings, and the distributor hold down bolt was loose, leaving the dist. free to move. I rotated the dist, back as far as I could go, and brought the timing mark on the crank pulley just into range of the index pointer above the pulley. I have now idea if the marks are in 5 or 10 degree increments or not.

    Any help would be appreciated.

     

    Thanks much,

     

    krmiller07

  20. Does anyone out there have any experience or advise on curing the noisy lifter syndrome on early model VG-30 V-6's? It seems to be worst when the engine is at operating temp. I have tried different weight oils etc. This engine has approx. 40,000 miles on it, and it's just as noisy as the one it replaced with 175,000 miles on it !

     

     

    Thanks,

     

    krmiller07

  21. Has anyone encountered a problem with a so called hydraulic damper between the clutch master cylinder and the slave cylinder? i replaced the slave cylinder after exerincing a 'dead pedal' i.e. clutch pedal went to the floor while driving down the freeway ! my mechanic bled the clutch line after i relaced the slave cylinder and I still have a spongy pedal. He claims theres a damper between the slave cylinder and the clutch master cylinder ? Any feed back out there >

     

    Thanks,

     

    krmiller07

  22. Does anyone out there have any experince with the installation of 'Super-Winch' manual hubs ? I found a great deal on a set ( New ) on Ebay and was wondering if they will work on an '89' Pathfinder-SE, with Automatic hubs. And is there any noticeable advantage to using them ? i.e. better gas milage etc.

     

    Thanks,

     

    krmiller07

  23. Ok, I took out both solonoids on the drivers right side or (passenger side) and they both function properly and look to be in great shape. I tried turning the slotted or (flat head screw driver) adjusting screw both in and out, and didn't notice any changes in idle speed, with either with the A/C on, or off, or with the blower on. Are you sure this screw isn't some type of 'idle mixture adjuster' ? Also if you look real close, on the front of the TB there are 2 adjustable 'dash pots' both with small (maybe 4-6 mm) lock nuts on them. One is fairly obvious to see, the other is somewhat hidden close to the TB and down,close to the throttle shaft springs and intake manifold. What is the function of this ? 'Idle up' for the A/C or electrical load ?

     

    Thanks,

     

    krmiller07

×
×
  • Create New...