bhermes

Thanks guys. I was able to get about 10 minutes today to work on this and removed the splice connectors for the 3 to 6 pin and replaced with solder and heat shrink from 3 to 2. Hopefully this gives me a more consistent voltage. I should get a little time tomorrow to switch out the splice from 1 to 5 with solder and hear shrink just to clean up the whole system. I did take a minute to look at the wiring diagram and noticed the green wire going everywhere so I understand the difficulty in seeing what I really was getting. I am sure some voltage drop and some inconsistencies. Again thanks.

SteveJ thanks for the reply. I kind of understand your reply; however, can you explain what problems I should be having with the way I have wired. What is not happening that should be happening and what is happening the way I have it currently wired. Just trying to see if it makes sense with the way the car is acting.

OK, so I went to replace my connectors for my alternator upgrade to solder and hear shrink and was trying to make sense of what I original did with the rewiring for the upgrade. It appears that I connected position (blue) 1 to position 5 (white with black strip) correctly but I actually connected position 3 (yellow) to position 6 (green) instead of position 2 (white). I would like for someone much more intelligent than me to comment on what this should actually be doing. The car is running and I am getting 14.7 volts at the battery but have some issues when I shake the mess I made and sometimes this effects the voltage. I will switch this to be correct when I make the solder / heat shrink change but would really like to understand what I actually hooked together. Thanks in advance.

Not an expert here but I had a similar problem in my 76 280Z. I had to clean and coat the tank but prior to this a lot of rust in lines. I did noticed that the fuel filter in my car showed very dirty/rusty fuel in the inlet side and very clean fuel on the exit side. In other words the filter was getting most if not all of the rust problem before getting to injectors (I realize you have carbs). I replaced my fuel filter a couple times. Also I know some people have added a clear filter in line to see the condition of their fuel. Jury is still out if I have got all of the rust out of the system but my fuel pressure, added a external gauge, is showing good pressure. Hopefully others with more experience will respond. Good luck.

Going with soldering and heat shrink tubing. I am just not that familiar with the combo splices. Thanks.

Just looking for some advice or direction. I upgraded to the 60 AMP internally regulated alternator some time ago and made the proper wiring changes. I have recently found some issues with my fusible links and have for the most part corrected those. Loose connections and some corrosion cleaned up and pressed down a little. Running voltage improved to 14.7V (good). Was seeing as low as 10V. Issue is that I used snap lock splices (big blue things) for the wiring change on the alternator upgrade and it appears that when I shake the mess of wires and splices I get some variation in voltage at the battery. I would like to redo the splicing using some other method. Is soldering and heat shrink tubing the way to go or is there another option that would be better? What is typically done? Just a reminder in the thread I have a 76 280. Thanks.

I am sure that this post is not a revelation but just thought I would post something here. I have a post, a few posts, in the EFI section and have been chasing a fuel delivery issue. After dropping the tank and cleaning up, fuel filter replacement, installing a fuel pressure gauge, adjusting several other things, it appears that the problem may have just been bad connection at my fusible links. If anyone out there is having issues and think it may be fuel related I am just recommending checking battery voltage and specifically the fusible links. I cleaned mine up some and the car is running much better now. A little early to completely know if the problem is 100% resolved but looks good so far. Systems were running a little rough every other start up, during 30 mile drives wanted to stall out a couple times for a few seconds during the trip (not consistent), stalling and restarting 20 minutes later (most of the time). I noticed that I had to charge the car to get it to start most of the time and the voltage was around 10V during running and finally the fusible links were warm/hot to the touch. Hope this helps someone.

You don't want to see that. One other note, I now have the buzzing noise when the key is in and the door is open. Never had this before. Still no dash lights and fuel gauge doesn't work but thats for another day. Thanks again.

Great guys. After a little cleaning and some light pinching yesterday on the fusible links (not fully cleaned yet with Deoxit) the car had good resting voltage this morning and started without any outside help. Running voltage was 14.7 at battery. Today's weather should be good enough for a ride so I will know more later. I have the fuel gauge hooked up and will also confirm no fuel delivery issues. I just love the willingness of people to help on this forum. I hope soon to be able to pass on what you guys have taught me on to others. One of the reasons i purchased the 280z, other than I just love these cars, was to learn. Never been a mechanic and still know little about cars but learning quickly. It has been a blast so far so thanks again.

I know that this is not really an EFI at this point but more electrical but hopefully I can close out this thread soon. Just for some education; why are the fusible links in the system? Why are they needed and not wired directly? This is probably a really dumb question but thought I would ask. I cleaned the connections some and squeezed down the flag terminals a little. I will see if the car starts in the morning and voltage is good. Thanks.

Mark thanks. I noticed that some of the connections at the fusible links are loose. Is it a bad idea to crimp down a little on the flag terminal to fit tighter? What should I clean the terminals with? I remember back in 1980, when I owned my first z car, that I had to poor soda in the fusible link to help start the car. OK telling my age now. I think when I moved the links around a little that I wiped some corrosion off of the terminals and things got better. I really hope this is the problem.

So it is possible that I have been chasing a fuel issue, and very well may have had a rust issue prior to dropping and cleaning the tank, but given that the fuel pressure has seemed to be fine, it appears I may actually have a voltage problem. We finally got a day above 20 degrees and no snow or ice and I went out and started the car. It did start without a jump or charge; however, the voltage at the battery was 11.5 volts. The car was running a little rough and as it ran the voltage dropped to 9.5. I did turn on the turn signal and then back off and the voltage still read 9.5. I played around a little with the fusible links and noticed that the one closest to the front of the car had some green corrosion and was pretty hot to the touch. I moved it around a little and the car shut off. The car was running a total of about 10 minutes. I tried to restart and had to jump with a charger. The battery after it started was 14.6 volts. Thoughts on the fusible links? Thanks.

Thanks Mark. I will continue to check fuel pressure and confirm voltage. Is there an easy way to tell if I have something on all the time draining the battery? Not sure what a normal battery would drain just sitting for a few days. It seems to only hold a charge at least enough to start the car for a few days max. Again thanks. Waiting for next day without ice on road and above 40 degrees.

If someone can chime in. I have always wondered how a low charge on the battery could impact car performance. I guessing with the EFI it can cause problems but not sure. Since I have not really seen an issue with fuel pressure, at least yet, I was curious if the battery could be the issue or at least an issue. After I made the alternator change, 60 AMP internally regulated alternator, I did not make the wiring change to the e-brake relay and therefore the light was coming on even when the brake was off. Just trying to understand, obviously I can easily replace the battery and check to see what happens. Thanks.

Fixed gas leak and another 20-25 mile trip with no issue in regards to fuel pressure. Trying to determine if I need to replace battery (constantly putting charger on to start). The car did run rough at first yesterday and I am just curious if this can happen if the battery is not fully charged? After a couple miles everything seemed good. I did stop the car after about 5 miles for 2 hours and the car started up without charging. Still need to get in a little longer drive and hopefully I will today. More ice and snow coming Sunday night.

Only got about 20 miles of driving on the car over the weekend. Nothing really to report. Car ran fine with no issues. Fuel pressure was good. Is there any chance that when the tank gets low the car would run bad? Pump not able to pull from bottom of tank? I have about 8 gallons in the tank now plus or minus. Going to see how this plays out and will reply back later. Back to cold weather and a little snow.

Finally got a day with roads clear and above 30 degrees. I went to go for a ride and I have a decent fuel leak around the fuel pump. I had some issues a few months back and had all of the fuel lines replaced and put on a new filler hose. Seems that something was not reconnected properly. Need to get this fixed and hopefully the drive will happen later today. Weather is going to be nice soon and I need to get this thing running good. I will be back with a post soon on what I find from the drive and the fuel readings.

Thanks. Siteunseen this is exactly what I am planning on doing. FastWoman, I have the pressure gauge on the windshield wiper ready for a ride. One additional item. I let the car idle for about 20 minutes and it seemed a little inconsistent. I then rev'd the engine some and got a nice (or not so nice) backfire and the car started idling much better. Any thoughts?

I am going to try and install the resistant pot today but still having problems understanding exactly how to install. The schematic in the earlier attachment shows it going inline with one side of the temp sensor to the ECU. In other words; temp sensor to pot to ECU back from ECU to temp sensor. Does this make sense? Thanks.

I know a drive is in my future. Just not looking forward to breaking down in zero degree weather. I will take a blanket. I am trying to install the resistant pot today or tomorrow. FastWoman, I don't recall, did you end up replacing the fuel pump and fixing the problem? Thanks.

Finally got back on the z today. I removed the FPR vacuum hose (just a side note my hose was only a few inches long) and the fuel pressure increased from 25-26 psi to around 36 psi. I am assuming that this is good. I have the resistor pot soldered and hope to be installing soon. I am considering moving somewhere warm. Getting sick of cold days. Any suggestions? Also, needing to find a z expert in the area just until I get a little more knowledgable. Not sure what else to check at this time. Thanks.

Sorry to be ignorant but I am a little confused on which vacuum hose to remove to check the 36psi fuel pressure. This thing is getting frustrating but having fun learning. The car seems to be really good in the driveway. Thanks.

Hopefully this does not show up twice. If so sorry. I finally was able to get my fuel gauge hooked up. I connected between the fuel filter and rail and ran the gauge to the windshield wiper. I have not been able to go for a real ride but here is what I have learned. During idle the gauge is reading 25 psi. During acceleration, raising rpm's, the pressure goes up to 30 psi; however, no matter the rpm the gauge will settle at 25 psi. I did drive just briefly in the driveway and the gauge was consistent at 25 psi. Based on the FSM and previous posts I believe I should be getting around 36 psi. Fuel Pump? Fuel Filter? Fuel Line? Anything else to consider? other than possible bad gauge. Thanks.

I know I should have some fuel pressure data by now; however, I did attempt a drive yesterday and about .1 of a mile from my driveway the car just about stopped. I was able to turn around and get the car back home going about 1 mile/hr. I did note that the rpm's stayed around 1500 throughout the 1 mile/hr trip. Any thoughts? Does this mean I am looking at a fuel problem for sure? I started thinking I might be having some issues with alternator charging or fusable links but it more and more seems like fuel. If I can get another decent day I will try the fuel pressure check. Just wanting to keep track of what is going on. Thanks.

I was not planning on using clear coat but it might be an option. I think I will contact the paint supplier and see what they recommend. The paint came from a supplier online, TCP Global and is a House of Kolor product.