Zed Head

He might just mean comparing the cylinder pressure readings between cylinders. It's more important than the actual pressures. All cylinders should create the same pressure, within ~20-25% lowest compared to highest according to the FSM and the Monroe rebuild book (although most people recommend a tighter number). For example, I've had two engines that tested within 2 psi, high to low, at about 175 psi for one and 180 psi for the other. The gauge used will affect the pressure measured though so the comparison is what's important. If you do find a pressure imbalance, a leak-down test would then give you more information about whether it's the head gasket, the rings or the valves.

Over here on the other side of the internet we have to make assumptions about how all of the other parts on your engine are working, so it's easy to miss a critical clue. That's why the methodical approach, with the FSM and a meter, works best, starting from scratch. I still see something that doesn't sound right. You said that you can hear the pump when you turn the key to start. "Start" is when the engine is cranking, so unless you disconnected the small wire at the starter, you wouldn't be able to hear the pump because of the noise from the starter turning the engine. Maybe you mean "Run" or "On" which is the position the key is in right before Start. The pump should not run unless the starter is cranking, or the the engine is running. Maybe you have a relay that's shorted, causing the fuel pump to run even with the key off? Or did you leave the key On when you went in to the store? You never said if the CSV that you took off had constant power causing it to stay open or if it was stuck physically. That would be an important clue. Something weird happened to cause several problems at the same time. CSV stuck, pump running, injectors open... I would break out a multimeter and take some measurements. How much time do you have left?

Somehow Wade must have cursed you when he mentioned that any injector could be open. Amazing. The more symptoms you describe though, the more it becomes apparent that reading the Engine Fuel section of the FSM would really help you out. There are a few things wrong with what just happened. First, the fuel pump should not have power when the key is on unless the engine is running. You couldn't fill your crankcase with gas unless the fuel pump was running. So that's not right. Kind of missed that in Post 1. And, unless the injector is physically jammed open, the only way to get constant fuel flow is if it's constantly grounded since the injectors always have power when the key is on. So your problem might just be a shorted wire on the ground side of the injector circuit. Or it could be a shorted ECU, which happens sometimes. You should get that FSM chapter and a multimeter and do some testing before you install the injectors, you might be wasting time and money. Or, at least, turn the key on with all of the injectors attached to see if they're all stuck or just one, before you install all new injectors. In the beginning, it looked a like a simple problem with a simple solution but now it's looking more complicated. It might be time to get methodical. The FSMs are in ZIP form on the xenons30 site, maybe that's why you couldn't open them. You have to download then unzip them.

Now it's looking like you might have a vacuum leak, a big one. All air must pass through the Air Flow Meter (AFM) otherwise the mixture will be lean and the engine will die or run funny. The crankcase is connected to the intake manifold through the PCV system also, so any leaks there will also be a vacuum leak. The oil filler cap, the dip stick, all vacuum hoses connected to the intake manifold, all must be intact and leak-free. If you've disconnected anything, thinking that you would re-connect it after you got the engine running, reassemble and try again. And check any hoses that you've reefed around while working on the engine to see if they split or cracked. The engine should start right up without messing with the idle screw. Counterclockwise gives a faster idle if you get close and need to keep it running.

On the headlights, if they're like a 280Z, the power is supplied at the combo switch, then runs through it, through the wiring and to the fuse box, on to the headlights, then back to the dimmer switch, where ground is used to choose low or high beam. So if you have continuity through the switch, but no power at the fuse box, then you either don't have power at the switch, or the circuit from the switch to the fuse box is broken. On the 280Zs the main power line to the combo switch runs through a fusible link. I looked at a 240Z wiring diagram but couldn't figure out where the power comes in. On the 280, it's a white with red wire and the fusible link mount is labeled as HL.

Sounds like your cold start valve (CSV) is stuck open. It's either getting voltage all of the time, instead of just at start, or it's physically stuck. Try unplugging the connector and see if it stops. If it stops, the problem is electrical and you can just leave it unplugged. Make sure you insulate the end of the connector though so you don't get a short. If not, you can remove it, block the intake port, and plug the hose,if you're in a hurry. It's only real value is for cold weather starting. It's more of a convenience than a necessity. The CSV is the valve/injector on its own separate fuel line up close to the throttle body. Follow the fuel lines if you're not sure where it is.

Did you see this Tech Article - http://www.classiczcars.com/forums/content.php?r=156-S30-Door-Window-Problems-and-Troubleshooting-Procedures It's very good, might help you out.

The fuel pumps are fairly noisy when running, especially if you're under the car in a quiet garage. I think that you might be looking at a new fuel pump, if you know that you have 12 volts at the wires, but you don't hear it and it doesn't move fuel. They don't like to sit for long, they're at the low point of the tank where the water ends up if it condenses in the tank. The fuel pump was the first part that I had to replace on my car. EFI pumps are expensive. The Ford F150 pump will work, with some modification to the fittings, and is a Bosch pump (late 80s/early 90s are the years to look for I believe), if you have access to a wrecking yard and want to try a cheap one. They're external and located on the driver's side frame rail. The auto stores all want $100+ for an aftermarket replacement. I've read stories of people getting them turning again by removing and cleaning. Might be worth a shot.

I have them on the back wheel cylinders on my 76 (with 78 struts and cylinders) and they work great, especially if you want to flush a lot of fluid through the lines (like, for example, if the car has been sitting for years before you got it). The final bleed seemed fine, the pedal is high and firm.

carpartsmanual suggests that they changed in 76 then stayed the same. At least the date of change is there. There do appear to be some possible errors on the site though, for example, the S30 front hubs are shown as all the same but some 240Zs seem to have a different type. http://www.carpartsmanual.com/datsunS30/DatsunZIndex/Body260Z280Z/2Seater/RadiatorGrilleBumper/tabid/1772/Default.aspx Good luck. I don't think that many people mess with their bumper shocks so finding someone with actual experience with both might be difficult.

Pretty sure that the fuel injection relay is by the hood release handle inside the cabin on the driver's side. It's combined with the fuel pump relay, two plugs in to one relay body. The only relay I see that would be by the battery, close to the voltage regulator (for 1977) is the seat belt relay or the AC compressor relay. If it is a 78 harness though, you'll be missing the voltage regulator (VR) wiring. Maybe the VR is what you're thinking is the fuel injection relay, it's in a similar looking housing.

You could compare drawings from the factory service manuals.

For what it's worth, I've removed mine and haven't noticed any unusual or irritating noises or vibrations. I have an RT-style diff mount also, so with the weight removed and no bottom diff mount, the cross bar with the suspension mounting points is much cleaner plus I have more ground clearance. Extra benefits.

30 Ounce, you're right, apparently, that it's a vibration or noise damper. Maybe it helps with the clunk. But the four plates on the front are stock. They all look like that, like someone learned how to weld while making them. I have a couple sitting n my garage. Many people take them off, and don't notice any difference. Clearance is clearance though. Do you need more than 2 mm?

Looks like someone's garage toy - http://www.luxurysportautos.com/detail-1976-datsun-280z-premium-used-8837479.html Might even have the original tires. Shiny.

That's some good info beerman. I had wondered if they were tied together by the regulator. I think it might explain why my temperature gauge started reading lower after I swapped oil pressure senders recently. The new (used) pressure sender reads more correctly now but the temp gauge reads lower, but also more correctly, assuming that my 180 degree thermostat is working right. The new sender had 0.2 ohms initial resistance while the old tested at zero. The old oil pressure sender looked aftermarket and the used replacement looked factory, for anyone looking to fix the fairly typical "zero" oil pressure indication at idle on their dash gauge. Just some odd facts for anyone else digging in to their gauges.

:bulb:You know, that much stretch looks more like a POs tuning trick, to get more advance sooner. Why would one stretch and the other not? How did you determine spring rate, for the auto store replacement spring?

Pretty sure that she bought Bosch injectors for her 75 car. Her current 78 car uses Standard injectors, if I remember, similar to those in your EBay post. I'm missing the point of the rock reference...

Do the input and output shafts move after the bellhousing is on? And are you putting the trans. in to 3rd or 4th gear when you install the bellhousing? If you don't, the 1-2 and 3-4 shift rods will move in to gear at the same time as you slide the bellhousing on, locking things up. Try putting the 3-4 rod in to 3rd gear before installing the bell-housing. Once it's on, you can install the shifter and pull it back to neutral.

Look about half-way down this page - http://www.datsunstore.com/index.php/cPath/11_35 Door gasket. I bought a set and they fit well. I think that they might be on sale because they have some marks from being stored folded up. Not perfect, but you don't see it unless you already know it's there.

If you're only getting only one backfire, and your AFM tested correctly by the AFM procedure, you should probably hold off on getting a new AFM. Since I've been reading the forums I haven't seen many cases where the AFM was clearly bad. I seem to be the only one (that I can recall right now) that had one that tested bad, ran bad (lots of backfiring, popping and stumbling at mid-throttle), and was definitely the problem, completely changing the way the car ran when I got a new one. Yes, 36 +/- about 1 should be the high pressure, then the FPR will draw it down when intake vacuum is applied. So, at idle you'll see about 31, then if you remove the vacuum hose from the FPR it will rise to about 36. The backfire and the fact that you bottomed out the idle adjustment screw are signs that you might have a vacuum leak. Don't forget that the crankcase is connected to the intake manifold through the PCV. So any leaks in to the valve cover or dip stick tube will end up as a vacuum leak. And, apparently,the EGR can rot out internally, feeding exhaust fumes to the intake constantly. I don't know if this would cause your symptoms though. Here's the thread describing it - http://www.classiczcars.com/forums/thread40886-3.html I would spend more time on the small stuff before going big on the AFM.

How long had the car been sitting before you got it?

The crop is from a car that is daily driven and parked outside most of the time. Plus it's been up in the low 80s here recently. Maybe it's a soy-based life form.

It's possible to get the top of the strut out without taking the lower control arm mounting points off but the brake line will probably get stretched and it might bind up and not flex enough to come out. I've got one out on my car but the other side wouldn't come out. Removing the four bolts holding the inner control arms on is so easy though, it's barely worth trying to get around it. After I loosened mine I said "I should have done that 1/2 hour ago". If you loosen them you'll have more room to drop the top of the strut. If the springs are stock you'll need a spring compressor. If the car's been sitting 10 years, the brake lines probably need work anyway. I would just take the whole assembly out, strut and control arm, with disconnected brake lines, and do the work. You'll probably end up there anyway. Wheel cylinders replaced, check the brake lines, all of that. On the wheel cylinders - the 76 and earlier (maybe 77 too) cylinder are expensive, like ~$45. You can swap in the whole assembly from a 78 car and use $15- 20 cylinders, if you want to save some money. Just mentioning before you get too far in to it, if it's possible.

For future readers. Might be a turbo AFM. I posted the same link in your other thread - http://forums.hybridz.org/index.php/topic/108020-afm-does-this-look-right/page__pid__1010448#entry1010448