two50below10

Zed, thank you so much for finding that thread for me! I was able to order the Bosch 0280161024 from Amazon of all places. Pricey little bugger, but hopefully it will match up and perform as the original. It may be a while before I am able to work on the car again now that the weather has turned, but I will post an update when I get it installed. Thanks again!!!

I have a ‘79 280ZX that has a leaky fuel damper. I have done many searches for the replacement part and have come up empty. It’s been out of production for many years and there is no new old stock either. So a couple of questions. Does anyone know of a replacement part number that will work? If no replacement is available, is the fuel damper really even needed? From what I understand, it is there to dampen any presssure spikes or pulses that may come from the nearby fuel pump. Thanks for any info guys!

Thank you to all. I agree that I have been given some great advice so far and I have tried to follow through on as much of it as I am able. Here is another update and a few more questions for the forum. I did go through and check all electrical connections at the fire wall. Everything looks good as far as I can tell. I then decided to hook up the fuel pressure gauge once again since I was concerned about the noise in the fuel pump sounding like occasional cavitating of the pump. This time when starting the car it ran fine for at least 20 minutes. I pushed the hood toward closed and took it into the street. Like usual it started to struggle, so I jumped out to observe the fuel pressure gauge and for the first time I was able to notice that the fuel pressure did start to drop off as the car began to quit. I had never witnessed this in my previous trouble-shooting. After getting it back into the garage I direct wired the fuel pump to the battery once again and for the first time the pump created very little if any fuel pressure. I am now strongly leaning toward something blocking the pickup in the fuel tank. I think that I am going to drop the tank again and start over with a fuel delivery problem. Thoughts? The last time I had the tank out I discovered that there are no access panels that allow access to the inside of the tank. The only openings are where the quantity gauge float goes in and where the filler hose connects. Additionally there is a baffle in the tank that keeps from view the fuel line pickup and fuel return. So, how would I go about gaining full access to the inside of the tank? I know some of you have talked about coating the inside of fuel tanks to prevent corrosion, but did you have access panels that made access to the inside easy? Also, I have noticed that the fuel tank will become pressurized after the car has been running for awhile. Is this normal or should this tank be breathing and equalizing pressure with outside the tank? Thanks again for any input you guys might have. Chad

I did a few more checks yesterday. 1) With the fuel pressure gauge hooked up I plugged the other end of the "T" that would go to the fuel rail and momentarily ran the pump. The pump was able to push the pressure up to about 72PSI. So I know the pump is good and strong. 2) I then connected the line back to the fuel rail and disconnected the return line back at the tank. I ran the pump to make sure I had a clear return all the way back to the tank. That checks good also. 3) After putting it all back together I was able to get the car started and kept it running yesterday afternoon while I had the fuel pressure gauge hooked up and the vacuum gauge hooked up. With the engine running the fuel pressure reads 30 and the vacuum reads about 16 and will go up to about 20 when revving the engine. Confident that keeping it running for 20-30 minutes at idle as well as revs up to 4000, I figured maybe my ghost problem had gone away. I pulled it out of the garage and into the street where it promptly died. Had to push it back into the garage (again!) 4) Later that evening I checked compression on all six cylinders. They were all 105 to 115. So I believe that checks ok. I couldn't find a number in the book other than that they should all be within 80% of one another. I had a friend who used to work on cars professionally come over to maybe help me diagnose and we couldn't get the damn thing to start. He pulled plugs and they were covered in fuel so I think fuel supply is not the problem. We checked spark while a plug was out and it is getting spark just fine also. I will definitely hot wire the fuel pump as suggested though to make sure that an interruption in fuel supply isn't the problem, because when the car struggles and quits it does sound as if the pump is not behaving. That could be a result of volts dropping off to the pump as the engine looses RPM and is about to quit though. I am leaning now towards the AFM. Do any of you have thoughts about whether that could lead to some of these shenanigans (runs great in the garage once and quits when in the street, then can't get it started later in the day)? Thanks again guys! Chad

Here is the latest. First of all the problem has gotten worse now. I can no longer keep the car running for more than just a few seconds before is quits. So whatever part is going bad it has started accelerating its demise. I am however narrowing it down a bit. I borrowed a vacuum gauge from a Friend and in just the few seconds I can get the car to run the vacuum checks good at around 16 and then even stays up after the car quits so I don't believe I have any vacuum leaks. I also purchased a fuel injection pressure gauge and have checked the pressure with the engine not running. I wired the fuel pump directly to battery. When activated it produces about 38-39 PSI and then when deactivated the fuel system remains pressurized at about 34-35 PSI. I also did the pressure test with the return line disconnected and paced in a container. The test returned the same results with a nice steady stream of fuel going into the container. The pump runs nice and smoothly and quietly. When the car is struggling to stay running the pump make noise and sounds like it is cavitating or failing. This leads me to believe that the fuel pump, fuel damper, fuel pressure regulator and filters are functioning properly and that I don't have any restrictions to flow. Although now I cannot check the pressure with the car running. However I don't think that matters now that I know pressure and vacuum are fine. So more questions for you all. Could it be the fuel pump relay? I don't know how these things fail. Are they either good or no good or can they fail slowly and possibly give the symptom that I have experienced with the sound of the fuel pump struggling and making noise? Although the relay wouldn't make sense if, when I unplug the coolant temp sensor it runs rich and comes back to life. I have even connected a volt meter to the terminals of the fuel pump to verify it is receiving twelve volts. It does receive twelve volts while the engine is running smoothly but can see the volts start to drop or fluctuate when the car begins to struggle. However I don't know if this voltage drop is the cause or the symptom. Could my problem be with the airflow meter or the ECU? Any more ideas guys? Thank you all for the info so far. I am definitely narrowing it down, but I sure could use more help. Thanks again, Chad

Ok, so here is what I have come up with so far. I did replace the temperature gauge sensor and the gauge is now working. I have determined that the coolant temp sensor is still good. I have verified this in two ways. 1) checked the resistance vs. a new one, and both read the same resistance and both match what the FSM says the resistance should be for given temperatures. 2) I then plugged the sensor connector into the new coolant temp sensor which is not installed on the car (just hanging there out in the air). It started and ran for about five minutes, and then as with the original coolant temp sensor that is still installed, the car started to struggle and finally quit. Here are some other observations. As you probably know, if you unplug the coolant temp sensor while the car is running it will run for just a second or so and then quit. I think I remember reading that it quits because it makes the mixture to rich when unplugged. So, with that logic in mind, I decided to unplug the coolant temp sensor when the car was sounding like it is about to quit. I could then keep the car running by toggling back and forth with the temp sensor plugged in and then unplugged. This leads me to believe that once the engine is up to normal operating temp then something is making the engine starve for fuel. Because when it is about to quit and I unplug the temp sensor it comes back to life with the added fuel but then will quit if left unplugged for more than about a second because of being to rich. Next, I intend to try and check the fuel pressure as suggested by a couple of you guys, to see if the regulator is bad. If fuel pressure checks good, do you guys have some other suggestions for me? Could it be a bad air flow meter? Starting to scratch my head here. I would really like to get this running now that the weather is getting nice. I am anxious to drive it! Thanks again for all the help so far, I truly appreciate it! Chad

Thanks guys for the input! I will have to do some reading on how to check the fuel pressure. What kind of special equipment is required? I also decided to go ahead and order the coolant temp sensor ($20) and the temp gauge sensor ($10, which wasn't working either). I will let you all know how I make out. Thanks again for all the great info! Chad P.S. One more question. Could the fact that I installed one of those clear inline fuel filters between the tank and the inlet of the pump make it too hard for the pump to draw fuel from the tank? I am thinking that it's probably not a factor because the car runs really great for 5-10 minutes before struggling and finally quitting.

After doing some more reading on the forum here, I am wondering if it could be a bad coolant temperature sensor. The car will start and run great for a few minutes while it is cold. After a few minutes it starts running rough and then eventually quits. I am then unable to get it to start until hours later or the next day. Any help or ideas would be much appreciated please. Thanks! Chad

Hey guys. I purchased a '76 280Z that had sat for a long time, although it has been driven some the last few years. I am in the process of changing out all the fluids and filters and such and have run into a problem with keeping the car running. Some backgropund info on what has been accomplished so far. I have changed out the brake fluid, coolant, oil and filter, differential fluid, with only the automatic transmission fluid to go. A few weeks ago the car began to sputter and then quit. Fortunately it quit as I pulled back into the driveway (had to push it into the garage though). When restarting the car again it ran real rough for about 2-3 seconds and then quit. If I wait a day and then try again it will stay running for awhile then quit. While it is running rough I could hear the fuel pump struggling so I figured the fuel pump was about to quit. So I have since removed and reinstalled the fuel tank to clean it out (the fuel smelled a little like varnish). I have replaced the fuel pump and even installed one of those clear inline fuel filters between the tank and the pump so as to not ruin the new fuel pump with any debris left in the tank. I have also replaced the fuel filter under the hood. Last night was the first test run with the fuel system put back together. The car ran great in the driveway so I decided to take it around the block. Well, it left me stranded and had to push it back home. So after this lengthy post I am wondering if there is there a fliter or screen inside the tank that could be clogged and causing the fuel pump to be starving for fuel? If there is, I sure didn't see any access to one when I had the tank out of the car. Please help if you have any ideas. Thanks! Chad P.S. This is the same car I received some great responses to about a possible wheel bearing making a growling sounds. As you can see I haven't had a chance to address that problem now that I can't even keep it running.

Guys, thank you so much for the help so far. Between work and my three kids I haven't had another chance to do anything with the car yet. I will definitley try to narrow it down before replacing parts. I am slowly in the process of changing all fluids and lubing required locations. I haven't gotten to the differential fluid yet. Everything on the car is pretty dry. I will let you know if any of the above happens to fix the noise. Thanks for the recommendations so far and the links to information! I am in Dubuque, Iowa, so if any of you are close by here or know of a recommended mechanic/shop in Eastern Iowa, Southwest WI or Northwest IL, I would be grateful for that info too. Thanks again, Chad

Thanks for the responses so far guys. Unfortunatley I live in a fairly small city with no one that specializes in old Datsuns. As for who works on my 280ZX, that would be nobody. The poor thing just sits in my garage and gets driven once a summer for about a week. It hasn't seen a maintenace shop for anything other that an exhaust system, and that was about 18 years ago. Now I hope none of you are thinking what my wife said when I was contemplating buying this car which was; "why do need another Z when you already have one that you don't drive". Nah, you guys wouldn't think that, you guys understand the need for more Z's in the garage. Back to my problem. Ok, so I'm not taking it to the dealer, a transmission shop is not probably the answer. Should I be thinking that I might need to ship this car somewhere to get it fixed correctly? Boy I hope not! Should I attempt this repair myself? Any other suggestions would be very welcome. Thanks again, Chad

Hello guys! First of all I am new to the forums here and after reading thru just a few posts I am looking forward to learning a great deal from all the knowledge that resides here. I am impressed already! Over the weekend I purchased a '76 280Z to go along with the '79 280ZX I have owned for 20 years. I bought the 280Z knowing that it has a very loud grinding/growling sound (grwow grwow grwow grwow for lack of a better way to describe it) that increases in frequency with increases in speed. This car had just shy of 21,000 original miles so it has spent much of its life sitting. I am hoping this sound is just wheel bearings that need replaced. Does this sound like a logical guess? Or could this be something more serious like differential problems? I am pretty good with tinkering with all things mechanical but after reading through the factory service manual that came with the car, changing wheel bearings is something I don't think I want to tackle. It sounds as though there are some pretty specific steps to be followed as well as some special tools required to do the job correctly. So my second question is, should I take this car to the local Nissan dealer, should I take it to a transmission specialist or should I be looking to take this to someone that has specific experience with Datsuns? I want to make sure it is done right! I look forward to hearing from anyone who might have some insight for me. I also look forward to being part of the group here. Thanks in advance for any help. Chad