FastWoman

... and regarding your running conditions, I think you successfully isolated the problem to the ECU and/or the connection to the ECU. Rather than to replace the ECU, you might try opening it up, pulling out the boards, and reflowing all of the solder joints with a 30 or 40W soldering iron. ZTrain fixed his ECU that way. Thermal expansion and contraction, combined with harsh vibrations, can cause these solder joints to go bad throughout the decades. I agree about the AFM. Give it a good check-over. If you bend the vane, your mixture will be waaaaay off. That happened on my old '75, and I didn't get the mix straight until I carefully tapped the vane back in shape with a hammer.

Jenny, I've never gotten that deep into polyurethane bushings but know people who have. Their advice to others is almost universally that it's easy to go overbaord and have your ride responding with the harshness of a buck ford. If I were you, I think I'd just replace what needs replacement as it needs it, and if the fresh rubber bushings don't do the job for you, then consider poly -- unless you're trying to put together a track car that you don't intend to drive on the streets. Your mixture: If nudging the AFM vane with your finger caused that much of a change in idle, I'd say you're idling way too lean -- the same way I was. You can try cranking in the idle mix screw (clockwise) to richen the idle mix without richening the higher-throttle mix. My screw didn't do much for me, though. Maybe yours will. I bet when you crank the thing in, your idle will hardly budge. Mine didn't. It's interesting that later versions of the AFM had two idle mix adjustment screws instead of the one. I don't know why that would be, except that it suggests they weren't happy with the way the original AFM adjusted. Again, my fix was the resistor. I think I'm now a bit on the rich side, judging from the light deposit of exhaust soot around the exhaust tip. I suspect my plugs will read a bit rich too. So I might back off the resistor a bit. The nice thing is that I have that option now on my car.

Or maybe crud from the tank could have clogged or jammed your fuel pump? Check your fuel pump for electrical conductivity. If you don't have any (infinite resistance), then that's your problem. Then try jumpering some power directly to it to see if it runs.

NICE!

You're welcome! Tlorber has a good point. I've read on this list where someone had a steel fuel line clogged with crud. It's not a common problem, but it could certainly happen.

Yoshi, when I lived in Texas and was having cooling issues in my '75, I replaced my 2-core with a 3-core, and it made all the difference in the world. I personally wouldn't put a cheap aluminum radiator in the car. There's a lot of discussion of this on the Miata forums (where I also hang out), and a lot of people buying the Ebay aluminum radiators find that they leak. Quality control is generally pretty bad. The alternative is to install the OEM plastic-tank version, which eventually rots. I did decide to go with an aluminum radiator in that car. CX Racing came well recommended -- economical, and supposedly no leaks. I haven't found time to install mine yet, but I've looked it over. It's not flimsy. The welds are sort of ugly, but I suppose that's understandable.

If you see it again, put a note in the windshield! Wow, the kids there are THAT rich! Good grief! When/where I went to school, most of the kids drove old beaters.

I feel your pain, Brian! I'm starting to think, "Geesh, what have I gotten myself into?" I wonder whether our machines would be capable of 30mpg with more modern EFI systems -- like the Megasquirt. Zewald, do everything Zed said! Great advice! Instead of listening for the pump to run, you might watch for fuel pressure -- e.g. with a gauge on the fuel line. Some pumps are only barely audible. (I can barely hear mine. It's a soft, low, rumbling.) If you have a fairly new fuel line somewhere (e.g. between the fuel filter and the fuel rail, you can just squeeze it with your fingers and feel it get firm when it becomes pressurized. Beyond that, just trace out all your wiring with a schematic diagram. Don't forget to check each and every connector for signs of charring. The pump draws a lot of current, and the contact in my big wire harness connectors had gone bad, charring the contacts and melting part of one of the connectors.

My antenna switch looks like that, but the lever moves left and right. It's a generic switch installed in an OEM insert. I presume the original switch fell apart. Does anyone have a pic of an original switch? Just curious what mine used to look like.

Some woman, when seeing my car, exclaimed, "Nice RX-7!"

Just write back, "Thanks for writing. Yes, all of the items are still for sale. I want $20 for the box of assorted whips and shackles. I'm asking $75 for the assorted "toys," which have only been lightly used and are still in excellent condition. I also have a wardrobe of leather costumes that I'm willing to let go for $500."

I think the AFM you have is doing just fine. You might have a problem with your BCDD (which leans the mix on deceleration, correcting afterfire), but very few Zs have functional BCDD units. Many are simply removed, and plates are used to cover the hole in the throttle assembly. I don't think mine works at all, but it's still on there. The AAV is a simple device, activated in no way by the throttle.. I think yours is just sticking. I'm guessing that it will get better with usage. These cars don't like sitting. I finally had a chance to get my Z out for a fairly long drive, and it came back with a big smile, purring with contentment. Thoughts of that idiot driver that almost hit us tonight were fading away. Before long, the weather will be a bit warmer, and I'll be doing a few other little jobs on it, as well as on its younger siblings, the little red Miata and the work-horse Saturn.

I'm not into lowered suspensions, fat tires, and hard steering (from fat tires). So it might seem like high water pants to some of you guys, but here's my combination that fits and works well. I'm running Bridgestone Potenza G 019 Grids, 195/60R15 on 15x7 Panosport rims: The previous owner was running T/A radials, 215/60R15 on the same rims, and those rubbed on the front wheel arches when turning the wheel moderately.

The problem is that it's pointed so far uphill that the pump can't get the gasoline to the engine. When you depress the pedal slightly, the throttle position sensor signals the computer (ECU), which then leans out the mixture a bit. Perhaps you're running a bit too lean. (How do your plugs look?) Possible causes are vacuum leaks, clogged up injectors, and/or a bad fuel pressure regulator.

Coolness! It might have been something electrical that "worked itself out" when coming into the light. I think day-to-day driving is what keeps these old machines going. Little bumps and vibrations keep the electrical contacts moving, and that wears through any corrosion that might accumulate. It's fine to be SLIGHTLY rich. You just dont' want to be slightly lean. Put in some clean plugs, and read them after a couple hundred miles, just to confirm your mix. I'm guessing your gentle pops out the tailpipe occur when you take your foot off the accelerator and the RPM drops just below 2500. That's when the ECU starts feeding gas again. Anyway, this is great news! Another EFI Z is humming along strongly now!

When you open the throttle very slightly, the throttle position sensor (TPS) signals the computer, and the idle enrichment is dropped. It might be that your engine is running too lean, and when you come off idle, it runs much too lean. When you say "backfires," do you mean a true backfire out the intake, or do you mean an afterfire out the exhaust? Backfire suggests lean running. Afterfire suggests rich running. What do your plugs look like?

As I recall, both of mine are on the driver's side, but I have a '78 280, not a 260. One is near the steering column, and the other is located on the side wall next to the driver's left leg, up high. I think the one near the steering column is for the turn signals.

Yes, the Eiko A-72 works great. It's the only modern-day replacement that's available. There are no issues with the slightly higher wattage, and the fit is exactly like the OEM.

Cool! I'll keep my fingers crossed for you. Even considering the error, I think I'd still trace out the wiring between your alternator and new voltage regulator before plugging the thing in and firing up the engine. After all, the PO apparently encountered something weird/wrong too, as evidenced by the burnt/snipped wire.

Congratulations, John! It's a great feeling to make some old machine spring to life. Don't let your wife goad you into selling your Z! It will eventually become a fine car again.

That's actually a 4 ohm speaker. You could wire two in series for a combined impedance of 8 ohms. Some of the older car radios might have an output impedance of 8 ohms, in which case this would work fine. If the output is 4 ohms, then the total sound output when driving an 8 ohm combination would be less than it would be when driving a single 4 ohm speaker. It's important to match impedances. And no, two speakers do not make a stereo or create a stereo effect. You have to have two separate audio channels driving those two speakers. That said, you might address both issues by sending the output of the radio into a power amp with a reverb circuit. It's cheesy, IMO, and you would be hard-pressed to find such an amp these days, but it would create a stereo effect AND drive both of your speakers with proper impedance matching. You could solve the latter problem (without stereo effect) with any power amplifier. A power amp mounts well behind either of the seats, perhaps under a seat, and perhaps even inside one of the tool boxes behind the seats.

Considering that you can reproduce the problem with the car standing still, you might get a volunteer to shift in and out of reverse, while you listen outside the car to determine where the sound comes from. For obvious reasons I probably wouldn't actually get under the car to do this, but you can narrow down the noise to a general area this way. Is it good to put in a manual, rather than a stick? I don't know how difficult it is, but sure, a stick is always better in a sports car. On the other hand, I don't think an automatic necessarily detracts from the value of the car. My '66 mustang had both a C4 automatic and power steering (which was quite rare and mechanically somewhat weird). I added power brakes. The car commanded a good price when I sold it. Of course automatics are more commonplace in Mustangs. I think there's something to be said for the "rare" factor.

This begs the question of whether it's better to have a prettier rear end, like Venus', or a sturdier rear end, like mine.

^^^ What Leonard said about dash caps. They're cheap, and they look good. They're clearly THE most popular interior restoration item for a Z. There's also a thread around here somewhere about DIY dashboard repair. The results are impressive, although perhaps not long-lasting. I've thought it might be possible to form/stretch black leather over a dashboard, perhaps with the help of some strong contact adhesive. It would have to be pretty thin and stretchy material -- something like kidskin. Do search around for this company that essentially rebuilts your dash, using new materials. The outcome will be much better than a "like new" (but old) dash, and I think the cost is probably about the same. Leon, the dash could be shattered in any number of ways. One way would be from a side impact. This issue of fiberglass in cars is a point of some debate. For instance many racers won't put fiberglass or CF doors on their cars, despite the weight savings, because of the possibility of a nasty intrusion injury. There are other less obvious hazards too. Some racers won't use CF hoods because in a frontal crash, the hood hinges can break off, and the hood can be shoved through the window like an enormous guillotine blade. By contrast, a fiberglass hood often has the good graces to shatter away, (semi)harmessly. I just wouldn't want the ball of shards on the INSIDE of my vehicle! Of course a steel hood is the safest, as it simply crumples. I admit I have no personal experience with any of this, so I might not be the best source.

Wow! Could be anything. Hopefully you fixed a bad connection somehow, and the problem won't leave you stranded 30 mi from home. I think Jetaway is right that it's a temperature-related problem. Thermal expansion and contraction will often rear their ugly heads in a coil winding. Once you do get the car running, let it idle on a very still (not windy) day until it is hot. Shut off the engine, and then try restarting it 15 min later after the engine heat has soaked the engine compartment (with the hood closed, of course). Also try starting your car when it's bone-cold. I think Jetaway might also be right about insulation. Carefully check the insulation around any of the wires you might have touched when you accidentally fixed the problem. You might have had a short to ground. My money is still on the ignition coil. If you hooked it directly to the battery and bumped the (-) to ground, you should have gotten a spark out of the coil. Regarding your fuel issue: Is your pump electrical or mechanical? "THANKS to everyone who offered suggestions. I am so grateful that there are people out the like you who care enough to answer an amatuer's distress call! You're all awesome!" There are a few pro mechanics on this board, but I think most of us are hobbyists/enthusiasts just like you. Two heads are better than one, and multitudes of heads, sharing ideas, experience and information, become absolutely brilliant!