cozye

I think it cleared up faster for you due to the injectors being opened longer which cleared out the air. My observations I can always hear a ton of bubbles getting recirculated though the fuel return line when open up the throttle some (more vacuum), it's the stranges sound coming from the passenger side floor. I did a ton of Internet searching on this subject, and this is what I came up with. 1. Lots of efi z owners started having the problem around the same time a few years ago. It was difficult to find because those are some really old posts. Before then, everyone said they never had the issue. This was like 10 years ago maybe. 2. Around the same time, various other classic car guys where having vapor lock issues that had not had them before (old hot rodders, etc). I found a few posts on this on some street rod forums where guys had original fuel systems. Some of these other classic car forums suggested that the addition of ethanol and reformulated gasoline was the culprit. One guy that seemed to have a pretty good chemistry background claimed that they had estimated based on some calculations that the boiling point of gasoline had been lowered about 15 degrees. Now consider that Nissan made some improvements in later years to keep the injectors and fuel rail cooler (injector fan), I would think that there were some reported hot start issues early on, but this must have been in very hot conditions. Maybe it was just a rare occurance in very hot climates under certain conditions. My point being that if the fuel rail was just shy of boiling most of the time, that would not have been discovered as an issue in early testing and for most drivers. But lower the boiling point of fuel 15 degrees and you have pushed it over the edge. The gas we buy today is very different than what was available in 1978' or 1988 for that matter. This is the conclusion i have come to, and the fact that in 10 years no amount z enthusiast have ever come up with a definitive cure supports this. I think the only way around it is to find creative ways to keep the fuel rail cooler.

http://cgi.ebay.com/ebaymotors/?cmd=ViewItem&_rdc=1&item=130650970722&ru=http%3A%2F%2Fwww.ebay.com%3A80%2Fsch%2Fi.html%3F_from%3DR40%26_trksid%3Dp5197.m570.l1313%26_nkw%3D130650970722%26_sacat%3DSee-All-Categories%26_fvi%3D1#ht_633wt_1021

. Im afraid so. I can't get over the hot looks, and the hot sound of a well tuned straight 6 with those triples. I've decided I won't be satisfied until I can lift up my hood and go "wow!!" It's on my fall project list.

I don't think there's anything wrong with converting it to carbs. Lots of people do it. The stock efi is a rudimentary system and an be finicky. I do think that you may be doing it for the wrong reasons though. You should be able to fix the efi and have a good running car for less effort than converting to carbs. I've got a spare 280 motor I'm picking up from a local club member. It's got an n42 head. I'm going to rebuild it and put triple webers on it . My reasoning is different though. I don't like the looks or the rudimentary functionality of the bosch efi. It clutters up the engine bay and doesn't respond to any mods or tuning. Ive decided that my new motor will be bumped up in performance a little, and like the looks, sound, and general nostalgic quality of the triples as compared to building my own ecu and building a ground up efi package for the new motor.

What is it with people and exaggerated descriptions. That isn't a rotisserie restoration! In any case I'll be watching this one. It's similar condition to mine.

I love that color lee, got any more pics?

I paid $3000 for mine, BUT ,.... I did all the fabrication and bodywork first. The 3k was just for a good block job, and paint. Included jambs and underside of hood etc... I'd say 4-5k is about right

Specific afm's are supposed to be paired with specific ecu's . They aren't necessarily going to work with your ecu. You will need to make sure that the serial number AFM you have is compatible with the serial number ecu you at going to use. Once you have calibrated via blues method, you should leave the AFM alone. It's not a great method to use that adjustment to make the car run richer, as it will require somewhere around 12 teeth or more to get the air fuel right, and the AFM spring will not have enough tension at that adjustment to work properly at higher air flow. Several of us have tried that, and the fueling gets way off at higher rpm. It will have no power at all end get like 12mpg. The best way is to put the potentiometer in the water temp circuit. Is there a reason why you don't want to try this?

Fontana is the place to stay. I haven't been to the actual z days events, but I've been down there on my motorcycle on the same weekend several times. It is mostly z32-34, but there are older z's as well. There will be a ton of z's down there. I thought about going this year, but I have a lot going on that month and might not make it. If I do go I'll likely take the 370 as it would be more ideal on those roads I've stayed at Fontana several times as well. It's nice. The lodge rooms are nicer than the cabins. Edit.. If you don't stay at Fontana (that's where the event is), then you will be at least 25 minutes drive from the event. Next closest place to stay would be robbinsville. You will feel out of the loop not being where the event is, as I'm sure 90% of the attendees will be at fontana

Well I guess I was wrong, someone did bid

Sarah, I forgot about the FPR being vacuum operated. I reckon you have a good point there.

Well I predict not a single bid. That should confirm what the market will bear

You can try putting some seafoam in the cylinders and letting it sit overnight, the drive it a lot. Considering your numbers are 30psi low on all 6, I doubt its stuck rings. I'd have to question. Your 41k miles. It's probably 141k, maybe even 241k. Mine has 113k on it and compression is around 160. I believe 175-180 is what you are looking for iirc. It's in the fsm.

I won't make that big of a difference. I did the same thing. Don't get your hopes up

Other than that, I think a rebuild is on order. I'm contemplating doing mine next fall

If you are 100% sure there are no vacuum leaks and your AFM hasnt been tampered with, and your throttle switch is working properly, then put resistance in line with the water temp circuit. The best way is to use a 5k linear potentiometer. The kind you have to use a small screw driver to adjust. Then solder two bullet connectors on it and you can hook right in where the harness connects. Use your vacuum gauge to get a close tune, it should get up to about 17 or so. Then use driving the car and plug reading to get it better. I found that when I tuned it for max vacuum, it was actually a little too rich and I had a bad stutter at off throttle. I've got mine running good now. Drives perfect.

No way that car is worth that much. It's not that clean. I'd say it's a $15k car. I hate to see a sturdy example of an early z gets hacked up like that. The series one means nothing now, it's a hybrid car. That said, it's a pretty cool car otherwise. It would be fun. I'd prefer a z motor personally.

Holy cow! That paint is absolutely gorgeous. You are a lucky guy to have such a talented friend!

My alternate theory was that ring wear caused reduce vacuum and that the lean condition could be caused by less fuel being pulled from the fuel rail. It's a long shot, but several things keep bothering me. One, not all people with 280's have the issue. Two, trying different ecu's doesnt help. Three, even when correcting the fuel mixture the vacuum is still a tad low compared to other cars that do not have the issue. The best I can get mine is around17.5 My compression results were in the low 160's which is a bit low iirc? It's Also entirely possible that the rings could seal better on compression due to the positive pressure, but leak more on the intake stroke due to the negative pressure?

Intake vacuum will pull fuel out of the injectors a little as well, you can't simulate that easily. I think you are heading down the wrong path with fuel flow diagnosis. I spent 6 months diagnosing this same type of issue, as did fast woman. Your fuel pressure is in spec, if you had a flow issue it would drop below spec when running. Any fitting on the manifold will work for checking vacuum. I use a t fitting off the fpr vacuum line. Brake booster is a good source if you have a fitting that works for that. Do a compression test. While I have arrived at the same conclusion as fast woman about ecu drift, I also have another theory but I need more examples to make it plausible

Sarah, did you ever do a compression check on yours ? What were the numbers?

It's not your fuel pressure. You can unplug the vacuum line to the fpr if you want to witness the fuel pump put out more pressure. What is your vacuum reading and your compression test results?

It's common on the 280. The are several very lengthy threads with detailed next steps, ie. ruling out vacuum leak, etc.. Once you go through everything there is a last resort fix but you must make sure it's not an air flow problem or other fi issue first. I think it's safe to say you have ruled out fuel flow as the issue.

Wow. Very generous of you. That's a nice shell, someone will make good use of it for sure.

I wonder if he knows that the crank is worth more than he paid for the whole car, ?