FastWoman

Argneist, there's not going to be any dedicated fitting for measuring fuel pressure. You'll want to hook a guage to a roughly 5/16" "T" fitting. Disconnect the fuel hose from the output of your fuel filter, and put another tiny length of hose on it (with a clamp). Connect the other end of that length of hose to the "T" fitting (with clamp). Connect the hose that came off of the fuel filter to the "T" fitting (with clamp). The gauge should be connected to the third leg of the "T" fitting (with clamp). Then you're good to go. I personally wouldn't see any use to an in-dash digital fuel pressure gauge. Fuel pressure goes up and down with engine vacuum, so unless you have both gauges going (fuel pressure and engine vacuum) and are very quick with mental mathematics, it's not really going to tell you much. Besides that, dashboard instruments aren't generally used for monitoring and diagnosing conditions that might cause your engine to run poorly. Rather, they are used to warn you that your engine is about to self-destruct somehow or leave you stranded. They're useless if they don't give you forewarning. Even an alternator/voltage gauge gives you forewarning -- to keep driving to the nearest shop, because you won't be able to start your engine after you shut it off. You'll know if your fuel pump goes dead, because your engine will immediately die. A gauge won't help you. As far as dirty connections are concerned, how many 30 year old computers have you seen that still operate? Those usually have soldered and gold plated connections and have probably been stored in not-too-hostile conditions (e.g. in the basement or in a corner of a storage room). By comparison, a car's connections are mostly crimped. They might be tinned, but not gold-plated. The car would have spent much of its life in rather hostile conditions. I'm amazed these electrical systems work at all! I haven't yet cleaned every connector on my own car, but then again it was largely working when I bought it. However, I've meticulously cleaned every connector I've encountered when doing other work, and I've rewired much of the engine compartment (which was the crustiest, most deteriorated part of the system). That said, if I had intermittent electrical problems all over the car, I'd just start pulling connectors and cleaning, without much attention (for now) to debugging. Can't hurt. If you've ever had mysterious problems in a computer, you might have been advised to re-seat all the connections -- pulling and replacing each card, each memory board, each ribbon cable, etc. It's pretty much the same approach.

Jenny, yes, you can lose the clips, and I doubt you can buy replacements, but you can make them easily enough -- probably just bending them from small paperclips. Andrew, you wouldn't believe just how badly my connectors were coming apart! In fact one of my fuel injector connectors completely crumbled between my fingers. Yikes! Argneist, if you're having lots of electrical issues everywhere, it certainly wouldn't hurt to undo every connector, clean, grease, and reassemble. It would be a bit of a project, but from the sound of it, I think it would be well worthwhile. Don't forget to undo your ground connections, clean/sand the metal, and reconnect -- with dielectric grease. If you ever need to clean out dielectric grease, BTW, you can do it with any number of solvents. However, I've never had to clean dielectric grease out of a connector. I don't think you need to get too crazy with the cleaning. Your interior connectors probably just need a quick spray with WD-40, working the connection a bit (plugging, unplugging, plugging, unplugging), applying grease, and reassembling. Engine compartment connections might require a light touch of 600 grit sandpaper. Note: Don't use a coarser grit, and don't get aggressive. You don't want to remove plating/tinning. In all honesty, I think craft paper (e.g. paper bag material) wrapped over a small screwdriver tip, wetted with WD-40 or Deoxit, is plenty rough to clean the connections. I would recommend that first. There's no need to remove your dash. Your light connections are around the steering column. The ECU connector is behind the left kick panel. The FSM will show you where all the other connectors are. I've owned two Z's now, and I've never had to remove the dash. In fact I've never had to remove the dash of any car I've ever owned. I do lots of wiring work, so if it were necessary, I'd have done it already. One other thing I didn't comment on before: You mentioned replacing the fuel pressure regulator and fuel pump for good measure. You'll go broke quickly by doing this sort of thing. Not only that, but you'll be depleting a scarce antique parts supply for the rest of us. I've never seen a bad fuel pump or FPR, and there's no reason to believe yours is bad. You should simply test your fuel pressure. If it's good, then both components are good. You can borrow/rent a gauge from many auto parts stores, and you can buy one for around $50. If you're inclined to replace parts just "because," then please make your cast-off parts available to others in the Z community, as most of them will be perfectly good (and we could use them). Good luck with the cleaning! I'm sure you'll iron out at least a few problems just by having clean connections.

See if you can spray some WD-40 inside the switch, and then exercise the switch quite a bit, turning it on, off, on, off. That might work. Zs-Ondabrain also rebuilds these switches. Or it might not be the switch.... Eventually you should upgrade to headlight relays, BTW. Those switches take a beating. No idea about your window.

Ramps: Yes, they're a bit scary if you drive the car up onto them, as there's a slight chance you could over-run them if you're careless. However, if you use them like jack stands, they're quite steady (better than jack stands), and you can roll down off of them when you're done. Jenny, the next garage I build is going to have either a lift or a floor pit! Cleaning connections: Deoxit is excellent, but even WD-40 can do a good job -- rub with craft paper around a screwdriver tip. If the connection is crustier than that, try wetting some paper with vinegar. Even crustier? Try 600 grit sandpaper. However, brand new connectors would be the best of all. If your connectors are anything like mine were, they're practically falling apart.

Good advice from everyone! Yeah, what they said! I still think it's electrical! Fresh oil change, ignition, clean connectors. You should know a lot more after that. About your "dumb question" -- If you have scrap lumber sitting around, try this: Set the emergency brake, and put your car in gear. Put a jack under the control arm of one of your front wheels, and jack several inches. Put a couple of 2x6 blocks under the tire, and release the jack. Jack the opposite control arm, and put 4 2x6 blocks under that tire. Jack the first control arm a few inches more, and add two more 2x6 blocks. Then you'll have 4 2x6 blocks under each tire. Change your oil, and then remove the blocks in the reverse order -- first two on one side, then four on the other, then the remaining two. You can also use jack stands, but they're frankly a bit difficult to get under there -- even the short ones. If you want to get fancier, buy a pair of ramps, but be aware that they like to scoot when you're driving up on them, unless you somehow block them. Another method is to do the above with a couple of 2x6 blocks and two ramps. Substitute the ramps for the 4-block stack. When you're done, just back the car off of the ramps. Easy.

To be clear, after you run SeaFoam through your intake and cylinders and knock down all the carbon/crud, you should change your oil anyway. If I were you, I'd do a cheap oil change -- Wix filter (never skimp) and some Castrol GTX 10-40. Fill the oil carefully to the top mark, jot down your starting odometer reading, and drive it. Make certain you aren't losing oil from a leak. Always park it in the same spot at home, and watch for (big) oil spots on the ground. Also while the engine is running, lie on the ground and watch for oil drips. (Maybe you're leaking around the oil filter or oil pressure sensor?) If you're not leaking oil, and you're still losing oil, then your engine is burning it up. Personally I'd consider a rebuild if I were burning a quart every 1500 mi or so, especially if I had tired compression readings. If I were losing (and not leaking) a quart every few hundred miles, I wouldn't hesitate to rebuild the engine. To put it into perspective, your engine seems to be burning almost as much oil as a 2-cycle chainsaw. Anyway, if you're looking for concensus, I think you have it from three of us on this list (again, if you're burning and not leaking the oil). Tell your three mechanics you're losing a quart every few hundred miles, and I think they'll reach a quick concensus too. You could nit pick over whether it's the valve guides or the rings that are leaking, but if I were you, I'd just do the whole engine. Idaho's suggestion of a swap would be your cheapest alternative to getting the car running again, but if you go that route, save the original engine (assuming it's really the original engine, with a serial number matching the plate on the lefthand side of the engine compartment). Matching numbers are important for the value of the car.

Ah, gee, the question was depressing enough (from my perspective), but I'm so sorry to hear about your clot! Get some rest, follow doctors' orders religiously, and get better quickly, OK? Meanwhile I think I'll start pondering how important it will be to get around to putting my affairs in better order!

Argneist, 3 quarts of oil consumption per 1000 miles is a LOT of oil! I'm starting to think mechanic #2 is right that you need a rebuild. That said, you might have other problems too. You need to sort through the entire fuel delivery/intake system to get everything right. The fuel smell in the exhaust is either from rich running or from misfire. It's not the problem, but the symptom. The fix for the problem is probably electrical, IMO.

Hi Argneist! Another '78! Your compression is a bit low, but I don't think that should make it run as badly as you're experiencing. You might be burning some oil, but that's another issue. The guidelines I'm familiar with say that the lowest compression should not be less than 90% of the highest compression figure. Having two adjacent cylinders with low compression might suggest head gasket leakage in those two cylinders. Are those two plugs the goopy ones? Oil pooled up in those spark plug pits could be from oil leakage around the valve cover gasket overhead. The sudden behavior changes that you describe (fine one minute and running badly the next, and then suddenly clearing up) suggest electrical issues to me. I think it would be a good idea to pull off every electrical connector on the engine, inspect it, clean it, apply some silicone dielectric grease, and reassemble. I'll caution you that the connectors are a bit crumbly at their age. An even better approach would be to replace all of the connectors you can. Here are the most common type on Ebay: http://cgi.ebay.com/ebaymotors/Datsun-280z-280zx-6-NEW-Fuel-Injector-Connectors-EV1-_W0QQcmdZViewItemQQhashZitem4cf2851c25QQitemZ330486324261QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories You will need 6 for the injectors, one each for the air bypass heater, cold start valve, thermotime switch, and coolant temp sensor. The 3-wire connector on the throttle position switch is available off of other more modern cars in wrecking yards. The big connector at the bottom of the air flow meter is not exposed to as much heat and probably stays in much better condition (at least on my car). The enormous connector on the fuel injection computer (ECU) behind the driver's side kick panel is very protected and should be in perfect shape, but it would be a good idea to remove it, clean, grease, and reinstall. Make sure the ignition is OFF when you do this! Do you solder and know how to use heat shrink, or do you know anyone who does? (You can also use crimp connections, but solder is better.) There's a little spring clip that holds each of these connectors on -- like a squared off letter "C". To undo a clip, you'll need to lift either the top or the bottom of the "C" with a tiny screwdriver, and then rotate the clip around the connector to free up the other side. You don't have to remove the spring clip entirely before pulling the connector off. After cleaning up the electrical connections, I'd put in a fresh set of plugs, drive the car a couple hundred miles, and then read the appearance of the plugs. They should all look about the same. If they don't, then you might have injector issues. Anyway, I would think you'll know a lot more if you just clean up the electrical.

What Zed Head said! When you step on the accelerator, the throttle lets more air in, the vane on the AFM swings open, the fuel pump cutoff switch closes, the FP relay clicks, the pump runs, and the system repressurizes.

Zed, I think he means the car idles at 1000 cold (when he first gets it to turn over). ODA, when it's cold, the oil pressure will be higher, but you're right that has nothing to do with engine performance. There's a lot that could be wrong with your engine. Cozye and I have gone through great lengths to straighten out our '78 engines (successfully), and Jennys280Z is in the process of debugging her '76. You can read Jenny's current thread to see what we've been doing. I believe your '77 is more like my '78 than Jenny's '76, but all these systems deteriorate over time and seem to suffer from the same problems: * vacuum leaks * bad electrical connections * occasional sensors gone bad * sometimes bad injectors * inaccuracies in the ECU Could be a lot of things. Tell us more, as Zed suggests.

Hey Jenny, nice work! I don't recall ever seeing a master cylinder sealed with caulk to a booster. I suspect if that junction needed to be sealed, there's be a gasket for it. Caulk between the booster and firewall would make more sense, but even that might be an optional sort of thing. Regarding the distributor, you can spend a lot of time trying to keep those funky things in repair, but all I have to do, if one acts funny, is to pull it off, take it in, swap for a new one under warranty, reinstall, and re-time. That's $100 well spent, IMO. I don't know if I have the right advance curve, but it seems to work just fine in my '78. No knocking or pinging. Just sayin'. Hey, we did get the red '94 Miata. It wasn't all I thought it would be, but I think it was a good enough deal. The car runs like a top and has a pretty decent paint job. The body is straight, with one replacement fender and the rest original. It has some mild underbody rust issues (nothing structural) and will be having lots of fun with cosmoline this spring. (I'll also be rustproofing many parts of my Z.) Oh yes, and it has a couple of leaks in the ragtop seals, just like every other convertable on the planet. I'll have to fix those too.

Maybe antique cars aren't your sort of thing. You can get pretty impressive power (225 hp) out of a BMW Z3 and look damned good in it. Maintenance is high, but it's a modern and affordable car. Probably a similar total investment.

Hi Jenny! I'm writing from the Amtrak. Waaaaaay better than a plane! I'll try not to be seduced by pretty red paint.

Once you get all the bugs worked out and have the car the way you want it, I'd say the maintenance isn't much different from any other car -- often even cheaper (simpler car than most). It's getting the car the way you want that's where you'll likely spend money.

I'm still here, Jenny -- all packed for the Amtrak now. Grand adventure! If I were you, I'd replace the distributor, even if it might not be quite the right vacuum advance. The reason is that when these things go bad, the breaker plate can freeze and stick, so that you get a random/irratic timing. Even better, find the right distributor, per Zed's advice. I have no idea about O'Reilly parts, as we don't have that chain here. Those refurb AFMs *are* high, aren't they! I see no reason not to buy used units and refurb them yourself. I doubt they do anything more than clean them up and adjust spring tension. They might even use beer cans full of water to do it!

I wouldn't worry too much about vacuum line diameters, as long as the hoses are secure and fit reasonably well. Yogurt cup test: You blow, and then you hold the pressure with your mouth (not inflating further) to see how long it takes for the pressure to dissipate. Anyway it sounds like you had a successful test. If you reached a bottleneck where you couldn't blow (much) more air into the thing, it must have been pretty tight. If you can paint your booster without voiding the warranty, I'd do it. The reman paint is usually of a rather poor quality. My reman alternator looked like your booster about a year ago and is starting to rust a bit now. Adjusting the AFM: I wouldn't say the mechanic did anything "wrong" when he adjusted the AFM spring to alter the mixture. That seems to be an accepted approach (e.g. Atlantic Z). However, I disagree with the accepted approach. I tried it and found that it resulted in a flap tension that was way, way too loose. The potentiometer wiper would be maybe 1 cm out on the carbon trace at idle, and the flap would logically peg out at too low a flow rate. The AFM in this state would be mechanically/aerodynamically "wrong." It makes much more sense that the wiper should be very near the low end of the scale at idle, which was the case with the spring tension calibrated per the beer can method (at least after I straightened out the mix through other means). Keeping the AFM to factory mechanical specs keeps the response properties as close as possible to design specs, and when all the other sensors are also within normal operating parameters, the final element that doesn't work is the ECU itself. Mine was delivering much too short a pulse width, as was Eric's. The solution is to proportionally lengthen the pulse across all air flow rates, temperatures, etc. Changing the resistance of the coolant temp sensor circuit seems to be the best way to execute that. It would be even better if the ECU had a calibration potentiometer just for that purpose (apart from the temp circuit), but it doesn't. Bosch/Hitachi didn't want us playing with that stuff and probably didn't really design our systems to be running properly 35 years down the road. Anyway this mod seems to work pretty well. When the engine comes up to 180F, the running parameters are all pretty well established and uniform, and the tunings that Eric and I have done are optimized for that condition. I've found the cold enrichment isn't all that bad on my car. I did have my engine die today right after I started it, but it was rather cold and hadn't been operated in a couple of weeks (snow, salt, sand). Another turn of the key and it ran like a top. This happened one other time since I had straightened out my mixture. Other than that, each and every start has been immediate and strong, and my cold idle has been excellent. So this approach seems to compensate for engine temperature pretty reasonably, even with the extreme adjustment I've made. (My "hot" temp circuit resistance is telling the ECU that the engine temp is about 50F, as I recall.) Anyway, I just have a different approach than the AFM spring adjusting folks -- an approach shared by others as well. But I think this approach is better. Well, I'll be away from my computer until Sunday or Monday. It would appear I'm taking a train to go fetch a little red '94 Miata. Hopefully it's all it would seem to be from a distance. Wish me luck.

Jenny, I'm no expert on timing, but I can tell you that my engine idles slower and less efficiently (hence lower vacuum) at the 1978 spec of 10 deg than at maybe 13 deg. I understand that's typical. However, I can also say with some certainty that the degree to which my engine bogged down at the spec setting was much greater when I was having lean running problems than after I fixed those problems. I could have easily set my advance to 10 deg, but I did give it a few extra degrees because the idle seemed happier and because I didn't feel a few more degrees would hurt anything. I wish I could tell you something intelligent about plugs; however, it seems you already know much more about them than I do. I just run the original spec plugs, and they seem to work well.

Well, I have to think that if someone were scrutinizing my rewiring work, they would give it an enthusiastic thumbs-up! However, I have to agree, in general. I almost always cringe when someone says they rewired something, because in my experience, that almost always means something pretty bad, if not scary and dangerous. In the same spirit, any time I hear "runs good," I automatically translate to "will move under its own power, but needs a LOT of work to run well." If I were you, I'd start with a general assessment of the PO's wiring skills. If you see wire nuts, hanging wires, twisted connections, connections covered in electrical tape, melted or charred wiring, and generally messy work, you should strongly consider writing off the wiring. It might be fixable, but it's still ancient, so even in an unmolested state, it would still be somewhat crusty and corroded. Your best fix, in the long run, might just be to install a new (reproduction) wiring harness to replace whatever was molested. While you're into it, be sure to do the available electrical upgrades. The thing is, I can't remember where I saw the repro wiring harnesses, and I can't remember how much they cost.

http://www.amazon.com/Littelfuse-ATD200BP-Anti-Theft-Battery-Master/dp/B001FXKJ0M I've never used it and don't know if it's any good. IMO, you're much better off plugging your car into a trickle charger for long-ish term storage. I'm sure there's even one that will plug into your cigarette lighter. Of course that does nothing for theft prevention.

Eric, I had to add about 2.5 kOhms in series. Your 1k might work, but it also might not. I suppose there's also a possibility she's running rich, after all the cleaning and such, in which case she'd need a solution to lower the temp sender resistance. Hypothetically, if that were the case, I think she could install a second temp sender in an unused thermo housing hole (at least mine has one available) and wire the two in parallel. But we'll get to that eventually. It's also possible some mechanic already installed a resistor in series. I say that because there was a fixed resistor soldered in series and wrapped inside my wiring harness. Jenny, do you know how to solder electrical connections, use heat shrink, etc? If not, it's pretty easy to learn. Here you go... This demo is overly compulsive, IMO, but it shows the process. No biggie -- even easier than shown. Anyway, these are things to come. First complete the checklist, and then we'll do the final adjustments. :-)

Just curious: Has anyone used pickup bed liner?

What does the inside of the tank look like? If rust is minimal, I'd just poke a pressure washer in the filler hole and blast the thing out. Let drain, dry. Rinse with acetone, let drain, dry. Then reinstall (perhaps after repainting the outside). If you've got extensive rust, then you'll need to eat it out and seal your tank. Just be aware of the anatomy of your tank. Mine has a large pickup screen in the bottom, which my radiator guy (who has rebuilt Z tanks) says will be eaten away by acids. He also says that a sealant like POR15 will clog a pickup screen. Of course if its got large holes in it from the acid wash, there's nothing to clog. If you pursue that route, just be sure to put a pre-filter inline before your fuel pump.

Andrew, that's awful. At least you and your passenger were not injured. Hopefully the same was true of the other driver too. Good luck, because traffic accidents and insurance claims ARE the Wild, Wild West. The other driver might miraculously produce a friend/witness who just happened to be driving along behind him and saw the whole thing -- and saw unambiguously that YOU proceeded through the intersection when the minivan had a green arrow. And because the accident was YOUR fault (according to them), you would be liable for the pain and suffering from the horrible neck and back injuries the guy received and for loss of income as the guy had to quit his job. This scenario played out for a neighbor of mine. Unfortunately I think many, and perhaps even MOST, people will trump up a personal injury case if they are able. In any collision situation, you need to round up witnesses, and you need to scan the area of the intersection for any surveillance cameras, so that you'll know whether you're able to subpoena surveillance tapes in your defense. Oddly, the car might be the least of your worries. And yes, when dealing with claims agents, you WILL be low-balled. Most of us in antique car circles know this is the norm, as there is no blue book value to establish the worth of our cars. You really need an appraisal (which has just landed on my new year's resolution list). FAIW, I think some appraisers will do after-the-accident, forensic sorts of appraisals. Good luck!

But Eric, you never tried my yogurt cup test! Seriously, when you do it, you'll immediately KNOW whether there's a leak (or a leak large enough to be of any importance)! I'm satisfied, now that Jenny has inflated her intake, that it's tight (within reason, notwithstanding a bit of blow-by past the valves and rings). Jenny, the EGR makes no difference. You're good. Question answered: Your intake is tight. Yay! Check your AZ distributor to be sure the shaft isn't bent/wobbly (which is a problem with some rebuilds). You can tell by seeing if the magnetic spur wobbles when it turns and/or the gap between it and the pickup varies as it turns. Also, in hind-sight, I would have asked your question about whether painting a part would void the warranty, and I'd paint that bugger before putting it on my car. (The vacuum advance doobob gets rusty very quickly.) I don't think a compression test would be affected by valve lash, unless one of your rockers is adjusted too tight. (Two of mine were! Yikes!) Pre-loosen all your spark plugs, and retighten them just a little bit. Warm up your engine, and then shut it off. Secure the throttle wide open (e.g. bungie cord on the throttle linkage). Remove all the plugs. Then test compression in all your cylinders, one by one. Make certain you turn the engine the same number of cycles for each cylinder. (Each cycle will push the compression gauge needle a bit more.) I'd suggest maybe 5 cycles. Making progress: No vacuum leaks. Cleaned up electrical connections. AFM tested w/in specs, except for the air temp sensor. (Did you ever get that figured out?) Soon to do valve lash and distributor (and timing). Do your coolant temp sensor and thermotime switch test OK? I'd re-test all your components from the level of the ECU connector, as that will also test all your connections and wiring. You're actually getting pretty close.