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NewZed

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Posts posted by NewZed

  1. what should the timing be set at and how do i check it???

     

    "how do i check it" is a worrisome phrase. The 280Z is actually a good car to learn on since it is very basic and everything is accessible and easy to see. But if you don't know how to check timing you should probably pick up a book about general auto repair and maintenance, along with downloading the FSM. You'll need a timing light to check timing and a fuel pressure gauge to check fuel pressure.

  2. ztore is having a sale. I think that these would do the job for less money but might give a little rougher ride, with urethane versus stock rubber - http://www.thezstore.com/page/TZS/PROD/wes-02a/23-4189

     

    They're selling springs also - http://www.thezstore.com/page/TZS/CTGY/wes-02a

     

    You might consider the wrecking yard for a replacement stock insulator and the zstore Eibach springs to get some ride height back, but still lowered.

  3. Did you see some sparks or smoke? There's no good reason for your fusible link to melt just by wiggling the wires. Maybe you have a bad connection.

     

    The general feeling on the internet sites is that the green fusible links are meant to melt at 40 amps (50 amps on the MSA site below). The gauge is shown in the FSM Body Electrical section, but good luck figuring out what exactly the auto parts stores are selling, and what you should replace the green link with.

     

    Here is one internet source for a stock style link - http://www.thezstore.com/store/merchant.mvc?Screen=SRCHM - search "fusible link".

     

    Edit - one option, if you trust MSA's 50 amp spec. would be to get an in-line ATO or blade style fuse holder and install the fuse of your choice. That's what I would do if I ever needed to replace that link.

  4. Once I wired it correctly the timing light would light up when I connected the pickup to the coil wire to the distributor but not when I hooked it up to the cylinder #1 wire.

     

    You were on the right track with this comment. Apparently the ignition system is working and the coil is creating enough energy for a spark. But it's not being distributed by the distributor. It has to be going to ground somewhere. Make sure that the path from the coil wire through the distributor cap, to the rotor, from the rotor tip across the gap to the individual electrodes and down the wires to the plugs is there, and not shorted to ground along the way.

     

    A simple start would be with an ohm-meter, measuring from an electrode inside the cap to the tip of the spark plug, and from electrode to ground. There should only be continuity to the spark plug tip.

  5. Your swap will be very similar to what's described here, except no turbo - http://forums.hybridz.org/index.php/topic/38461-240z-260z-280z-turbo-swap-guide/

     

    The 240Z small fuel line issue can probably be found with searching. The high volume/pressure EFI pumps will apparently develop enough back pressure on the return line to increase your fuel pressure, making it uncontrollable by the FPR, so that's a valid concern.

     

    Read through the L-Series forum in the FAQ/Powertrain section for more general EFI L6 information. - http://forums.hybridz.org/index.php/forum/90-l-series/

  6. Since it's okay to muddy this thread up I might as well throw in two plugs worth. On a completely stock 1976 280Z EFI engine I found that having plugs 3 - 6 all indexed between 10 and 2, and plugs 1 and 2 at 7 o'clock and 5 o'clock, respectively, gave a poor and rough idle. Getting 1 and 2 indexed between 10 and 2 also, smoothed the idle out dramatically. This is with NGK BPR6ES-11 plugs. I was surprised that indexing had a big effect, but it was real and noticeable. I only put the effort in because my engine's idle just doesn't seem as smooth as it should be, even with essentially identical cylinder pressure numbers and all new tuneup parts.

     

    And a couple of side notes - projected tip plugs really do increase the tendency to ping/knock/detonate, requiring retarding the time a few degrees. And the batch firing seems to give a different idle depending on which sets of two cylinders each start the injection cycle. Stopping and restarting the engine can clear up a bumpy idle.

     

    Just wanted get that out there while the details were fresh...

  7. These old ECUs don't have the "limp home" mode that the newer computers do. They're primitive.

     

    Have you measured fuel pressure with the engine running? Fuel flow doesn't tell you much. Your problem sounds more like it's fuel related, with the lack of high RPM power, the dying and the backfiring.

     

    By the way, I think that your 1977 280Z is supposed to have 188 cc injectors. Are you running non-stock injectors or is that a typo?

  8. Also, mine is one of those rebuilt MSA ones and all I've heard is that those are bad news.

     

     

    I'm curious about what you heard about the MSA rebuilt AFMs. What did you hear and who did you hear it from? There aren't that many sources for rebuilt AFMs. MSA'a are actually rebuilt by Fuel Injection corporation, whoever that is.

  9. The AFM, in general,is supposed to match the ECU. The ECU takes the voltage returned from the AFM to determine injector open time. I don't know if the Nissan engineers actually changed the potentiometer circuit or the spring tension or the shape of the air flow channel between the various AFM numbers, so couldn't say what the difference is between those two AFMs.

     

    Some AFM numbers appear to be the same AFM in function, except for small differences like the fuel pump contact switch. But there might be bigger changes that cause problems like you're having. The ECU and AFM inputs and outputs are kind of mysterious.

     

    You might get more ideas if you gave some history on the car. Did it run with the "wrecked" AFM? Has it ever run? Can you put the old one back on and get it to run? Things like that.

  10. What year car? Why did you buy A31-625-000 if yours was A31-601-000 (or vice-versa, can't tell which is old and which is new from your description)?

     

    The backfiring sounds like what mine was doing when I had a bad AFM.

  11. 1978 used the same ECU so the AFMs are probably not that different. Maybe Nissan tuned the spring tension differently for emissions or use with EGR. I had a 1978 with AFM # A31-604-000 and the same A11-600-000 ECU that my 1976 had.

     

    There are only a few circuits in the AFM, the potentiometer circuit that tells the ECU how much air is passing through, the air temperature sensor and the fuel pump contact switch. Getting the right parts together is a worthy goal but "running rich" is a common problem and has many causes. You might check the other reasons for running rich before you go too far though. Fuel pressure control, temperature sensors, TPS adjustment, etc. Here is a thread from classiczcar that tells a story - http://www.classiczcars.com/forums/showthread.php?42574-MPG-timing-fuel-and . He had a similar dilemma.

     

    1975-1977 are your best candidates for finding the right AFM part number. Check the glue blob under the cover to see if it's been tampered with. It's very common for people to get inside and muck around with the spring tension for "tuning" purposes.

  12. That is the right ECU number for 1976. What is the number for your current AFM? It might not be mismatched for the ECU. For example, Nissan changed the part number for 1978 AFMs to show no fuel pump contact switch but but some of them still have the parts. 1978 has the same ECU number, but a different AFM number.

     

    What problem are you trying to solve?

  13. What is it that "goes away" when you shut the car off, after letting it run for a while? I saw your other post, which is more descriptive since you say that you have spark.

     

    If you have spark, and the engine turns over, and it ran just a few seconds earlier, then fuel would be the place to look. Do you have fuel pressure on the second try, and are the injectors firing?

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