NewZed

The fourth one down has a bunch of good ideas... http://forums.hybridz.org/index.php?app=core&module=search&do=search&fromMainBar=1

Is it sensitive from mid-throttle on, or only from closed throttle on (what you might see in stop/go traffic). One is driver skill, the other might be a mechanical problem. My car recently (like last week) had the throttle plate sticking in the throttle body at closed throttle, I couldn't get the throttle moving again without it popping off the closed position and bucking forward a little. It would even hang open a little when it got really warm, raising the idle to 1500. I took the AFM boot off and cleaned out the "varnish" where the throttle plate sits in the bore with some Scothbrite and carb cleaner, plus honing out the bore a hair where the plate sits (Scothbrite will remove metal), to make up for wear on the set screw (the set screw lock nut is impossible to reach). Just another possibility. I am assuming the turbo throttle bodies are similar.

Thanks rossman for a real-world example. It's good to know that my pickup tube is probably not about to fall off or disintegrate. Tony D, thanks for the detailed advice on a surge tank. The Tennis Ball Can tank description gives a good visual. With some math, I should be able to figure out how long the turn can be before I run out of fuel. Maybe I'll design it for the 217 N to 26 W merge ramp...

Your question is a little confusing... Your ZX should have a voltmeter, not an ammeter. And if you follow the main charging wire from your alternator you should find that it already goes to the battery positive terminal through a fusible link. At least according to the 1981 diagram. What year is your car and do you really have an ammeter?

Saw this the other day - http://forums.hybridz.org/index.php/topic/70721-l28-injector-spacing/page__p__669437__hl__%2Binjector+%2Bspacing+%2Bfor+%2Bfuel+%2Brail__fromsearch__1?do=findComment&comment=669437 It's close. Old link is broke. New, better - http://forums.hybridz.org/topic/70721-l28-injector-spacing-port-dimensions/

I've never dropped the tank. Overall, the fuel supply system hasn't shown any signs of problems, besides this low fuel level cornering issue. I thought of a few new search terms, "surge tank" and "sump" and looked around using those. I get the impression that, as Tony D suggests, the issue is not that abnormal, based on all of the racers modifying their tanks, and various reports of fuel starvation, usually on modified cars though. I have an aftermarket Airtex 8312 fuel pump and an Aeromotive regulator (not for performance, the old ones just wore out) that might flow more fuel (from inlet to return line) than the stock setup (I'm guessing). I wonder if this isn't emptying the fuel line system more rapidly than the tank baffles were designed for, so instead of an sir bubble I get empty lines. The Airtex is reported at 30 gph, but I don't know what the stock pump flows. Thanks for the ideas. I guess I'll just fill up sooner, or drive slower, or start modifying.

I have an essentially bone stock 1976 280Z but hope that someone with track experience may have experienced this and have some knowledge and advice. After using about 13 gallons of fuel (based on several fillups), with the gas gauge getting close to E, apparently the pickup tube in the tank is getting uncovered on wide left turns, if I am accelerating. The engine loses all power, acceleration stops, usually I'm heading straight about then, and the engine regains power. It only happens close to E. This is all just normal road driving. Is this common or do I have a bent or holed pickup tube? I'd like to get closer to using the 17 1/8 gallon capacity of the tank, but don't know if this a left hand turn issue only or if there's an abnormal problem. Full disclosure - I have a small dent in the tank right next to the differential housing where the car slipped off a floor jack. Is the pickup tube in that location and maybe I bent it up? Any ideas appreciated. Thanks.

Might be that the ECU housing needs to be grounded and yours is loose. I don't know if it grounds through the data cable or not, but if it grounds through the housing, that could be checked and easily fixed. Bump once, lose ground, bump again, get it back...

That really only leaves injectors opening for way too long, or a bad gauge, from my limited knowledge. If the gauge is mounted right on the rail as the pictures I've seen of the Pallnet rail show, then the pressure you see is what should be at the injectors. It sounds like your setup is plumbed correctly. Might be worth connecting another gauge to the inlet side of the rail to verify that the gauge on the rail works right. In your first post you mentioned tuning the ECU. Is the 300ZX ECU tunable? How are you tuning it? That information might help someone understand your issue. I don't know anything about them. I would post a picture of your rail, gauge, FPR and MAF setup and tell people how you're tuning the 300ZX ECU. Good luck.

5 minutes worth of puddled fuel. That's a puddle. Didn't think of that. I did think cold start valve stuck open though. Do you have one connected? You mentioned the thermotime switch. You didn't actually say that the gauge showed zero psi. When the car is running, the gauge needle on the rail is at zero? And you have the FPR adjustment stud backed all the way out? You should either start the car or run the fuel pump and turn the FPR adjustment stud in to increase fuel pressure. If the FPR and gauge are working, the gauge needle will move up. This would be a good test of whether or not your gauge and FPR actually work correctly and that your fuel lines are connected right.

Hey, I just re-read your first post and realized that you said that your mechanic said "buy new stub axles with u-joints". Mentally, I replaced "stub axle" with "half-shaft." You either heard him wrong or he's not too familiar with the cars. You might have him look again or have someone else take a look. The half-shafts just unbolt, remove four nuts at each end, and can be removed complete for easy u-joint replacement.

He might confusing the drive shaft u-joins which are not replaceable (without some custom work being done) with the half-shaft u-joints which are. Or he might not know that the retaining clip is on the inside of the yoke, not the outside like most domestic cars. Check out Post #3 and #6 here. Zs have Type 2 (Post #6) half-shaft u-joints. If you can get up to the Portland area, this guy has a used set of half-shafts that you could bolt right in - http://portland.craigslist.org/mlt/pts/2008316276.html Or you can get new u-joints at most auto parts stores and either do them yourself or have them installed.

It looks like 280zbeet is in just a little bit over his head. He is pretty obviously relaying what he reads here to his mechanic and his mechanic is then telling him what he thinks (eg "the guy working on the car has already hooked the haltech up to a laptop and said everything looks fine"). And back and forth. So what looks easy for those with experience is not actually so easy for 280zbeet. He is translating both ways but not actually turning the wrenches or running the laptop. So in this case it is COMPLICATED. Just my impartial view. Probably doesn't help anything but gives another perspective. If the mechanic could get on here it might help.

I think I saw a similar post on another forum...? I don't believe that your car will run with no pressure at the fuel injectors. You need pressure, quite a bit, to squirt the gas out of the little holes at the end of the injectors, when the ECU tells them to open. How do you know the FPR is at zero psi? Do you mean the regulator is set to zero or do you mean the fuel pressure is measured at zero? Zero psi fuel injection doesn't make any sense.

Non-running is probably less than the Low Retail - http://www.nadaguides.com/default.aspx?LI=1-22-1-5013-0-0-0&l=1&w=22&p=1&f=5014&y=1982&m=1254&d=802&c=13&vi=79166&z=97225&da=-1

I think that your coil should have battery voltage (12 volts) at both + and - terminals when the key is on. The primary winding current flow (in conjunction with the capacitor/condenser) is what energizes the secondary windings. If you have voltage at the + but not at the - then I believe that your coil is not working right. And that's why the - goes to the ignition module. When the current flow to the capacitor side is stopped (points closing or module triggering) the coil sparks. My limited understanding of coils and ignition systems...feel free to shoot me down if I am off-base. p.s. I think that in the past you have mentioned a smoking condenser. The condenser is part of the ignition circuit and needs to be working also. You can test all of the components with a multimeter. Edited at 2:46 - think I had something backwards.

Here's a few links to stores that sell links. What was Br(brown) in the manual and on the fixture labels is now known as red (color fade with age apparently). On the busted connection, it's just electrical. Datsun crimped some of their main power line connections so I don't think that soldering is necessary as long as the fix is protected from the elements. http://www.datsunstore.com/advanced_search_result.php?keywords=fusible&osCsid=95598e23ad3319492fefbe5e6efabfd5&x=0&y=0 http://www.courtesyparts.com/kb_search_result.php?chassis_id=59&keywords=fusible&Submit_Button=Go&cat=1 http://www.thezstore.com/store/merchant.mvc?

Check your master cylinder also. The two tend to go bad around the same time. Also, if you adjusted the pedal while working on it, you might have it too tight. The master cylinder piston has to retract completely to let fluid in to the lines. There are a ton of posts on the various forums about master, slave, "clutch won't work", if you want to get more viewpoints.

http://www.thezstore.com/page/TZS/PROD/12-4067

The booster and master cylinder are model specific. The only input from the engine is suction from a vacuum line. So the one for a 1971 240Z would be correct. 260Zs were made in 1974. 1977 was a 280Z. In the states - I think other countries may have had different models available in different years.

Carb and choke cleaner works great and doesn't leave any residue.

Can't really help you with your decision. But I thought that the N47 did come with injector notches since it is a late model head. Below is a quote by 1 fast Z from a thread on cylinder heads. I have an N42 head on an EFI 76 and an N47 on an EFI 78 myself. Just trying to clarify for you, and make sure I know what I think I know. Even the 75 head should have injector notches. "N42= This head came on all 75-76 and EARLY 77 cars. It has the 47cc chamber, and this head is a fully open head. This head was used on a fully dished piston, to where no quench was used. It has the largest of the valves much like all 280's did. 44mm intake and 38mm ex. This is the last of the L heads that came with bronze seats. This head has Square ex ports, and has the Injector notches as well. N47= This head came on all mid 77 through the 1980 z cars. It has the same exact characteristics as the N42 except that it has the cast in ex liners. These liners were cast in place, for the reason that when the motor is running, these liners get so hot that they glow red hot, and with that you get the advantages of them burning off the hydrocarbons that are left over in the exhaust charge. This is the first head to have hardened seats put in all of the valves." http://forums.hybridz.org/index.php?showtopic=62691

Did you stick your finger in there and see if it comes out with fine gray grit on it? I noticed when I was working on mine that the rod from the fork to the slave cylinder is not in-line with the bore of the cylinder. Close but not perfect. So there is a side load on the piston in the bore, which probably led to the galling. The inexpensive cylinders probably are made of less durable materials. OEM if mine fails again within the next couple of years. I've read that they last longer. Failing slave cylinder stories are all over the internet. I wonder if having the cylinder chromed would help. Might be cheaper than new.

I have seen it recommended, either here or over on classiczcar, that they be taken apart and cleaned before installing, whether from Autozone or Schucks or wherever. I took my last Wagner brand slave cylinder apart before installation and it had about 2 cc's of oil inside with what looked like honing residue in it. It looked like they just pulled it out of the final finishing machine at the factory, threw the piston and seals in and boxed it up. The one before that, that I did not clean, lasted about three weeks. This one is at about three months, after cleaning. The first one lasted nine months. The two that failed had both galled a spot in the cylinder, in the middle of stroke, causing the seal to fail.

bjhines, I went to the S wire focus because HeatRaveR said he had replaced that bad wire and connection and still had the problem. Looks like he has other bad connections. HeatRaveR, congratulations on finding the cause of your problem. You might check the wiring diagram for your car first, to see where the S sire goes, before tearing things apart. There should be one at the back of the FSM. http://www.xenonz31.com/s130/reference.html Careful with those wires or you'll end with a "where's that smoke coming from?" issue next. Like your avatar...