Xenn

So updates: It was still acting up, so last weekend I finally got around to upgrading the distributor. Wow the car runs better, most notably at low rpm and when cold. However it still decided to act up, yesterday i decided to finally put the other ECU in, i was hesitant because it was from an older car that had its battery hooked up backwards once, but when i ripped it out it turned out to be nissan remanufactured (who knows from when) I stuck it in and it works great, seems to run the engine differently than the original ECU which is odd, but its improvements rather than faults, i have plans to replace the alternator soon but will wait to see what the new ECU does first. As for the heater it seems to be its own issue thst just has bad timing, i kind of think its the temp sensor in the blower housing it sits in going. Turn signals I am unsure, its too rare to diagnose, and too inspecific, someone needs to stop feeding my car after midnight.

+1 for Offspring. And yeah, last time a car decided to fail on me far from home i was basically in a different state and had to scrap it instead of fix it, I think i might cry if my z did that to me. Its also my only car right now because of that, so i would probably lose my job if it did that. Yay poverty!

Its working again as of this morning, I dont feel like its a lose wire, more like some component that disconnects sometimes when it gets too hot, or switches on/off then cant switch back. The turnsignal (heater may or may not be related, still unsure, havent had a squirrel cage for my blower motor again until recently.) only does this after the car has been turned off. Yesterday for example, went to work, everything ran fine, delivered things to the post office at the end of the day and realized neither turn signals nor heater suddenly work. Still not working on the drive home. This morning getting in the car, i hit the turn signal, it clicks once, then after a second delay starts blinking on my dash and clicking/running normally, still no heater, 2 min down the road i try the heater again and it works. New turn signal capacitor, new blower motor, fusable links swapped out for breakers, no blown fuses, etc. Sometimes it feels like someone has a switchboard for my cars electricals and messes with me by turning things on and off randomly.

Oh, I completely forgot, there is another seemingly related set of problems. About half the time when it dies, suddenly afterwards once its running, the turnsignals and heater blower no longer work for a few days, then will randomly start working again (hazards never stop working) Occasionally like today, it will happen on its own, (though i have noticed a few hickups). Does anyone know off the top of their head if these two components (blower and most likely turn signal switch) share a connection or ground anywhere in the car. I dont have time for a few days to bust out the multimeter and start testing things, and by then it will probably be working again.

Hmm, I havent thought of that, i was going to pass on doing the alternator upgrade because mine looked new, but switching to the internally regulated zx alt might help. As it is im going to swap the distributor out this weekend then hold back for awhile, I dont like to go past 2 solutions to fix a problem before it popps back up, in case I do fix it, I can help others out when they have the same problem, and not just say "replace half your car, i did and the problem went away for me."

Ive been waiting to do the distributor upgrade until the atlantic z car club tech tips website was back up, and by damn its finally back. Ill swap out the distributor/ignition module this weekend.

Hmm, i thought i replied over the weekend... Anyway, usually the worst times are after I stop, it can be as short as turning off the car, getting out, checking mail, and getting back in. It is usually worse the sooner I try and restart the car. It can also happen while driving, ive been stranded in a few intersections becsuse of it, ususally the RPMs will jump from 700 or so to 900-1000 for a split second then fall to 4-600 and barely run with no power, gassing it kills it, black exhaust (not nearly to the point of coalstacking, but black exhaust, not clear). It starts and stops as fast as someone flipping a switch. Occasionally ill get a little hickup while driving, a split second lack of power like the engine died for a moment or had really bad fuel/spark issues. I thought the ECUs had a fail mode that could run the car until it started to get up to temperature where it would die because it was treating it like a cold engine, am I wrong? And i replaced the TPS the day i posted this thread, it hasnt had a no start condition yet since, but has still had the "hickups".

Its not that, it can manifest as soon as i turn it off, and occasionally while driving, and it only gets better after the car has been turned off. I say it runs rich because i can see the carbon in the exhaust coming out, until i adjusted the TPS the car actually generally ran lean. All new injecters, including cold start, and i really did clean every connector i could find in the engine bay (as well as label all the wiring on the ecu harness. New temp sensor, temp gauge sensor, and thermotime. Oh and ive ran it with the hood up with it doing it before, and recently, wiggled connections and played with the throttle, made sure coolant was circulating all of that. Nothing helps. Worst is sometimes it will go a month or two without doing it, sometimes twice in a week, usually worse when there is a lot of rain, and i live in Washington.

So im here again, i only ever show up when i have a problem I cannot solve, this one i have been racking my brain on for most of a year. The car: 1978 280z, mostly stock, lots of new parts and a spart car to check parts against. The problem: Occasionally the car will have an extremely rich running condition, it will barely run, idles around 400, has no power and giving it any throttle usually kills it. Rarely this will happen when i am driving. Usually it is after i run it then stop (such as to run in a store) come out and this manifests. It acts somewhat like as if the ECU is running in a worst case senario, and as the car gets hotter it runs worse until it dies and wont start. Its not fuel pressure, new sparkplugs and wires, ignition coil, cleaned distributor cap and basically every ground in the whole car, new AFM, injecters, TPS, basically you name it, ive swapped it out, next on the list is ECU just to see if it helps (since i have a spare). Heres the kicker(s) whoever owned it before me A sucked with electrial systems to the point where the heater didnt work because he plugged the harness (the power side of the switch to motor to harness 3 way connecter) upside down, like crammed it in backwards then sold it as a broken blower motor, so who knows what else they screwed up elsewhere (fuse box is a mess too) and then B at some point an aftermarker alarm was installed, then disconnected, but looking at part A, who knows well. So here are my questions, if it is electrical, what could cause it, and if its the alarm, how do i go about looking up what type it is and finding instalation instuctions? (I could only ever find a patent # never a buisness, even with google.)

The Fuel pump is on a separate circuit, when i got the car AFM was jacked and the circuit runs though that, so I bypassed it, hmmm...

So I did tests today, it was in fact my AAR, even though it is new, I also noticed that the hoses going to it were more shot than I realized so I replaced them with heater hose for now. So If the valve only closes when it has been off and warm for awhile, I am guessing it is not getting current to the heater, so is my best bet to just replace the wire.

Sorry, didn't have time to test my car yesterday, got a new gun, as for the picture, I do have that line, I recently checked my vacuum setup against a good 280zx and made sure everything was connected correctly/valves turned the right way. For me that line runs from the BCCD to the thermal VV, then to the EGR systm

Ill pinch off the AAR just to make sure and play around with the TVV today and let you guys know tonight how those go.

BCCD is filled in on the inside of the intake manifold, there are 3 openings in front of the TB, one connects the the vacuum advance and carbon canister, the other is the other I talked about earlier, and the big one in-between that goes to the BCCD, i filled In it because I suspected a long time ago that might be a problem, it helped other problems, not this one.

I have thought about that, it connects my i wanna say idle air valve (vacuum source) to my intake manifold via a tube that runs thought the BCCD (that I left unplugged) it has 2 plugs and screws in under my AAR, I am not sure how it functions/what its purpose is though. Does that seem likely?

im using the 79 air intake, and my AAR is new and seems to be working fine, even if it got no power the coolant would heat it up and close it. I was thinking some heat activated valve on the throttle body possibly related to EGR. I know the 76 TB have a valve or solenoid that physically adjusts the throttle during cold start to raise RPM, does the 79 have an internal one? It acts like there is a valve that opens too far/gets stuck open and lets too much air in, and slowly closes when the car is off, but I cant tell if it is running lean or just revving high.

BCCD is filled in, 76 EFI. 79 Distributor, alternator and ignition module. I have been upgrading it as I go, but the problem has persisted since I got the car running.

79 280zx engine in a 76 280z body So I have searched the internet, and replaced most of my engine trying to solve a problem I cant seem to fix, a problem others have a variation of. After a cold start, as part of the warm up systems, there is something that kicks in about 2 minutes after the car starts that is NOT the air regulator. Other people who have this problem it usually causes their car to die, or idle very low/poorly, it causes my car idles at about 2000 RPM. The problem is sudden, and takes about 20-30 seconds to take effect, but for others it is instant. Once my car is warm and has sat for about 20 minutes the problem goes away and it will idle correctly. Vacuum is fine, everything in the thermostat has been replaced (including the thermostat) other than the water temp gauge, ner air regulator, connections have been cleaned etc. My two thoughts are the ECU is haywire, or there is some valve that kicks in other than the air regulator at warmup and mine is shot. It is related to heat somehow, taking longer to kick in on cold days, shorter of warm days. Always around that same 2 minute mark though. My question to you is what cold start system kicks in about 2 minutes into warmup? Is it likely the ECU is doing this? I have found a lot of people with this question, but never an answer, I hate to bug you guys but I am stumped.

Problem solved, it was a red wire with blue stripe spade connector coming down next to the center console.

Rheostat is good, anything else common that might make the lights go out.

76 280z So This weekend I removed my heater blower motor and replaced my heater core hoses, when all was back together, later that night I discovered my dash lights no longer work, runners and break lights still work, combo switch is new, fuses and fusible links are good, the 3, 10 pin connectors are connected, so from what I can read online it comes down to two things: A) Rheostat is broken (unlikely has been working fine until now, but will check later) Or I knocked a ground or connector lose, this is the main reason I am here, I would like to know all the grounds and wires related to dash lights that might be under the passenger side, anything with pictures would be much appreciated, The guy who owned my car before me butchered the wiring so it would have been easy for me to knock something loose. I have been looking around but can find little on the subject, most of the time it is combo-switch or fuses, but given my rummaging about under the passenger side it is fairly likely I knocked something loose.

As per This thread I am going to buy a new ZX matchbox ICU and hope that solves my problem, I want to know if anyone knows what brand I should buy to avoid having the same problem as last time, is there only one company that makes them and everyone else distributes them, or what, there is Back Arney, WD Express, Standard motor products, etc.

Alternator is new, dizzy is remanufactured, think i might pick up a new ignition module to be safe. The problem started about a month after i rebuilt the top end, or 2-3 months after i replaced the dizzy, 6 after alternator. It didnt start until it got hot out.

Sorry zed head for the late reply to your question, I was checking this site and posting via my phone, and it didn't like to update others posts. Also yes, grammar is key, and I can fail miserably at it at times (remember, put your kids through private school, public school is just a business nowadays) ANYWAY thank you for the ignition module answer, as well as the ignition coil voltage answer. It made no sense to me as to why it would work with me doing that either from an electrical standpoint, or a logical one, it was a hunch I acted on, I didn't short it to the chassis, I connected the + coil to the + bat, and the - coil to the - bat, it sparked once, then wouldn't spark again, simple alligator clip connections not held for more than a second, that is the absolutely only thing I did to it that time (check one thing, see if it will start, check another, see if it will start, one at a time, no more) and it fired up without a problem, with those wires disconnected, even with a spark-plug wire still off so I could listen for spark. As for checking the voltage, I just took a voltmeter put the negative to a ground, and touched the positive to one terminal then the other, I was worried the voltage on the negative terminal was 12 because I assumed that since it was the negative post, and the chassis is basically a negative ground to the battery, the voltage potential between the two would be 0 since I assumed the negative post post simply grounded out seems I was wrong, but I come here to learn, a basic circuit knowledge only helps you so much on a system as complex as a car.

Above all else, and bar none the weirdest thing thst happened, hooked a direct line from the battery positive to my coil positive (which also kicks in my accessory) then hooked a linefrom my batt negitive to my coil negitive, it sparked once, then not again, disconnected the wires, hopped in my car anf it started without a problem, even still had a sparkplug off, i guess at this point my question is what could cause my ignition coil to behave that way, that being having positive voltage out of both terminals until i forced the current to go the right way?