ISPKI

Hey guy. I have not had much time to test any of these ideas yet on account of how much rain we have been having. However, I was reading about updating the ignition system on my 77 280z to a newer ignition system and was wondering if I could get a bit of info from you guys that know about the system. I read about swapping a 280zx distributor into the car which seems like a reasonable idea since a rebuilt dizzy is only marginally more $ than a replacement TRIG unit. Correct me if I am wrong, but, just upgrading the distributor will eliminate the ballast resistor and the TRIG unit correct? Since the 280zx dizzy has the ignition unit mounted on it and utilizes the full voltage of the system? I have also read good things about the MSD 6AL ignition module, any suggestions on that?

Ah hah. I see it now. Thanks for the education lesson. I will add that to my list of items to check.

Does a 77 280z even have an ignition module? I search and get ignition coils for 280zs, and the ignition module for a zx.

What is a TRIG box? I cannot seem to find any info on it.

37 is too high? the FSM says 36.3 or something. Do you have any idea what the vacuum pressure should be in the manifold? I could test that next. Something I forgot to mention is that I tried to test to see if there was a vacuum leak by simply pulling a vacuum hose off the manifold. I figured it would make the idle worse, or cause it to surge or something, but it didnt change how the engine was idling at all.

Oh also - Here is what I just replaced over the last few weeks: Removed Intake manifold - cleaned inside and out, new vacuum connections sealed with teflon tape. Cleaned injectors, replaced all gaskets for all injectors. cleaned fuel rail replaced all fuel lines on the rail as well as fuel hose clamps replaced water temp sensor replaced thermotime switch replaced thermal transmitter replaced thermostat replaced thermostat housing gaskets replaced intake/exhaust manifold gaskets, studs, spacers, bolts, nuts etc cleaned throttle body and replaced hose clamps replaced throttle body gasket replaced all vacuum hoses and clamps replaced PCV, hose and clamps replaced all the EV1 harness connectors with new connectors - including AFM and TPS connectors replaced valve cover gasket and bolts replaced dizzy cap, rotor. new NGK spark plugs and spark plug cables were also installed and thats about all I can remember

Hello folks! I just recently finished getting the manifolds and gaskets and sensors and thermostat and what nots back together on my 77 280z. So far so good, the thing starts easily warm or cold now - no more draining the battery trying to start it. My current issue is this: After around 5 minutes of idling after I turn the car on (idle at start is around 1200ish in 80 degree weather) there is a soft click from the engine bay and the idle drops to around 500. Usually when it kicks down from the warm up idle to this extremely low idle, it will just die immediately. It starts right back up but the idle is super low and unstable. It will drive however, and it revs up relatively nicely (stutters slightly when I first stomp the throttle) although it does not feel like it has alot of power. I went through the fuel injection bible and started with the air bypass regulator as that seemed to be most inline with the symptoms. My vehicle does not have EGR. I tested the regulator at the control unit by checking continuity which it has. I also tested it by pinching off the feed line from the throttle body to the regulator once the idle dropped down. This did not change anything so I do not think that is the issue. I have checked many of the vacuum connections, mostly by spraying carb cleaner on them. No leaks anywhere. This leaves valve adjustment and BCDD. When I went to look at the BCDD I noticed that the wire was not connected. Through more research I found that the BCDD wire should be connected to a white/black stripe wire over by the coil. I found that wire plugged into the A/C pump which seemed really odd to me. However, after switching the wire over to the BCDD, nothing changed. Also - I have a fuel gauge hooked up inline. Fuel pressure appears good - sits around 37ish at idle, increases smoothly and quickly when throttle is applied. My next step is going to be testing the circuits listed under step 6 of the bible, unless anyone has any other suggestions. Will post back later if/when I get time to test the system.

It was 1/8 NPT = /. The guys at my local Car Quest found a brass fitting that fit, although I did have to clean up the threads a little bit.

Thats the worst part about sludge buildup! In my (albeit limited) experience, you cant really tell that its in there until you either purge the tank with acids or you blow your fuel pump and clog your lines. Guess which one was the experience I had... Keep up the good work, you inspire others like myself to keep going on our restoration projects.

Tamo, I have been reading through your build thread and I think you should get a clear universal fuel filter and install it inline immediately after the tank/before the fuel pump. After sitting for that length of time with old fuel in the tank, there is most likely some amount of sludge and/or rust piled up in the tank - My 77 280z sat for about a year with maybe a gallon of gas in it and it had some rust and sludge deposits in the tank. I installed one of those cheap universal fuel filters and it has collected about half a tablespoon of sludge/rust in it after a few months. The filters are available at many parts stores and online, usually for a few dollars.

Im just going to plug it up and see how she runs.

It does indeed, it goes through into the chamber. Sort of an odd place for a vacuum fitting being all the way over in one of the intake ports. All the other vacuum fittings are in the main plenum chamber. Any intake manifold that I have seen does not have a hole there or kinda sort looks like it is plugged with a bolt or something, but I cant find any really solid photos of that spot.

Also - Just another bit of information. I am fairly certain that this intake manifold was off a vehicle with a manual transmission as it had several components found only on MT vehicles (according to the FSM). These were all disconnected but still bolted onto the throttle body and thermostat housing.

Hello gents! After replacing the intake/exhaust manifold gasket, sensors, thermostat housing, wiring, injector harness and generally cleaning up and organizing the entire fuel rail area, I am finally at the point where I can start up my 77 280z again. The problem is that there is an open threaded hole on the intake manifold and I can not figure out what went there. There doesnt seem to be anything left that is not plugged in so I am thinking that it may have been plugged but would like to confirm before I try and start it. I have viewed numerous photos online and in the FSM and I cannot figure out what this thing is/was for. Attached is a photo of the hole, circled in red...

As others have stated, the EFI system in these vehicles is extremely delicate. Literally any tiny issue could cause the symptoms you are experiencing - bad ground, vacuum leak, clogged fuel line, corroded connectors, missing clips on your connectors. Take a look at the tiny vacuum line feeding into the fuel pressure regulator - mine was slightly torn when I got my car, not enough that you could hear the vacuum, but enough that it was not letting the regulator operate properly. Also - check for fuel pressure by tapping into the fuel line with a gauge between the filter and rail. If your connectors are badly corroded or your connectors are missing their locking clips (most of mine were missing) I would contact FricFrac on this forum about his replacement connectors for the L28E - very worthwhile investment IMHO.

Not sure if a 77 280z and a 78 280z are very different but the FSM states that fuel pressure should be around 36. From what I have read, this should increase when throttle is applied - my 77 280z idles around 34-36 and pops up to about 41 at WOT. From reading the FSM, the temperature sensor can cause many issues with how your vehicle runs if it is not functioning. I would start with replacing that (around 10$ at rockauto) and see how it does from there. Also - Make sure that the vacuum line at the FPR nipple is the correct size and has no leaks. I replaced mine with a slightly larger diameter because I could not get the correct size on and the car would not run at all. I tried putting hose clamps on it as well, but it still would not run. My buddy managed to get the correct size vacuum line on with his tiny girl hands and the thing starts and runs fine.

Hello everyone, I find myself in need of a new thermostat housing for my 1977 280z. Mine broke when I installed a new thermal transmitter. Will need to be shipped to 06035.

I actually just ordered an entire set of connectors from FricFrac on this forum! The rubber boots on all of my injectors, afm, temp sensor, tps, thermotime switch are corroded/dry rotted and have completely fallen apart. Many of the connectors are missing the clips to hold them in (the AFM specifically) and all the connectors are green and fuzzy on both ends (except the AFM somehow). I cleaned them as best I could but I just decided to order new connectors and new sensors. I will have to see about cleaning up the injector connectors and I will likely wrap the plugs in large heat shrink tubing to keep moisture out once I install the new connectors.

I had a string of issues with remanufactured CV axles on my civic. Replaced both front axles twice before I got a good set, and of course one of them got punctured by a tree branch weeks later. At least they have lengthy warranties. One of them didnt even have the right splines on it!

Hey guys, I was just wondering if the plugs for the fuel injectors on a 77 280z are identical to the plugs for the water temperature sensor and some of those other, similar looking sensors. They appear to be identical. The reason I am asking is that the plugs for my injectors and sensors are all torn up and corroded really badly and I would like to simply replace them with new ones.

Finally got these photos uploaded. Could anyone tell me what this thing under the throttle body is? My buddy and I were thinking it was some kind of IACV. This is what the yellow wire for the temp gauge was plugged in to.

Well, it was a pain in the ass but I finally found the yellow wire. I started at the gauge and followed it through the dash down to the blue plug that connects the instrument harness to the engine room harness. I cut the jacketing on the harness open at about a dozen spots between that plug all the way down past the alternator, around the front of the car and up the opposite side. The yellow wire seemed to follow the harness for the lights. Anyways I found it plugged in to something underneath what I think is the throttle body. I took photos of it that I will upload when I get back home later tonight. Regardless, I unplugged the yellow wire from whatever it was plugged into, cleaned the connectors and plugged it into the thermal transmitter. Turned the car to "on" and the gauge now reads way down on the cold end. Tested the wire by grounding it and the gauge popped up all the way to the high side. Get to check that one off my list, and add whatever it was plugged into onto the list.

Well, I have scoured the engine bay for several hours but I have not been able to locate the wire for the transmitter. I am going to assume that someone must have yanked the entire wire out for some reason. From reading the wiring diagram in the FSM, the temp gauge has a plug directly behind it that connects it to the instrument harness. There is then another, larger plug connecting the instrument harness to the engine room harness that should be on the passenger side of the cabin. All I should need to do is find the plug connecting the instrument harness to the engine room harness, locate where the yellow wire is supposed to be on that plug and then run a fresh wire all the way to the engine bay.

Well the connector for the thermal transmitter seems to be missing completely. Do you know if the yellow wire routes into the same jacketing as the wires for the water temp sensor? I am guessing that whoever had this thing before me cut the transmitter wire out completely so I may have to run a new wire straight from the gauge in the dash. Does the wire run into anything between the transmitter and the plug for the gauge?

Well just had a "duh" moment. Tell me if this is correct. There are three sensors plugged in to the thermostat housing; Temperature sensor that sends a signal to the ECU, Temperature Sender that sends a signal to the temp gauge, and Thermotime switch that actuates the cold start valve. The temperature sensor and thermotime switch have the same connector while the sender for the gauge has what looks like a bullet connector/barb thingy. I think I have had them switched around all this time...and the single barb connector is not even plugged in...in fact I cant find the plug for it.