Lani Kai

Hmm, it appears to have fixed itself. Thanks though.

I was driving today in my '78 280Z and all was well, but after I briefly switched on the hazards, the indicator switch no longer works. Pressing the hazard button still makes the lights blink, and the headlight dip still works so the stalk itself is still functional... Fuses seemed fine as well. I'm guessing it will be something simple and silly, but does anyone have any idea what would be causing this? Thanks

Thanks! TPS: Inspected with cover off, seems to be working fine. Tests OK at ECU connector. CTS: Replaced. Tests OK at ECU connector for the given temperatures. CSV: Replaced. Verified that it is not stuck open when not connected. AFM: Replaced. Rebuilt unit from MSA. CTS wiring: ECU connector tests don't suggest any problems. Haven't ripped the wiring apart to see if anything has been added, but it doesn't look like it's been touched in the past. FPR: Tested fuel pressure at rail and verified 35psi It's running a bit better than before as I think some of the carbon buildup has burned off.

Also, I just removed the old ECU from the car (previously, I hadn't bothered removing it from the bracket while I tested the new one). Carved on the back side of the ECU with a knife or something was the word "BAD" I wish I was making this up.

Yeah... So I was just going to post that... It was indeed out of gas. Now it runs pretty strong but needs some timing work. Also runs pretty rich.

I think there's been a slight misunderstanding. While the engine started and stopped running, the new ECU is perfectly fine. It still lights up Christmas lights as if it were December, so I don't think it's been fried or anything. My current problem lies elsewhere.

Well, I went and bought a new ECU, and the car started up right away with the CSV unplugged, which is something that I've not been able to do in a long time. I also tried the Christmas tree light test and confirmed that the injectors are firing at regular intervals. However, after running for about 20-30 seconds at idle, it just died. After that it started once and died again, this time for a shorter period of time. Now it just cranks and cranks and doesn't start, although I suspect it might be flooded. I'm going to let it sit for a while. In the meantime, I guess I now need to consult the section on troubleshooting for "starts then stalls"?

Oh right, 10 is ECU power.

With ignition to ON, ~12.7V at connectors: 1, 10, 14, 15, 30, 31, 32, 33 1: Coil trigger input 10: Fuel pump? The EFI bible has a test from 10 to 20 as AFM to fuel pump but it's for a 1975 and mine is a 1978. 14, 15, 30, 31, 32, 33: Injectors With ignition to OFF, continuity at connectors to ground: 4, 5, 16, 17, 21, 35 4: Start signal circuit 5, 16, 17, 35: ECU to ground 21: Cold start With ignition to ON, continuity at connectors to ground: 4, 5, 16, 17, 21, 35 Is there anything above that suggests something is awry? Sticking a Christmas tree light in the injector connector and drawing a wire from ECU connector to ground causes the light to turn on. Drawing a wire from coil - post to ground and connecting to ground causes a spark at the wire on every tap, but does not seem to make injectors fire even after more than three taps. Coil is new. Cold start valve is also having problems (always has). It's constantly getting a current and keeps continuously spraying fuel. Previously, when the injectors were working, I had unplugged it because I don't really need it. Right now, the only way the car can start is with the cold start plugged in (the car is running on fuel from the CSV only)

Was doing some testing just now and I'll post what I measured at the harness in a bit, but now everything completely dies when I turn the key to "Start" It won't turn over at all at the moment.

I checked for continuity from #1 to the coil negative and I had continuity. Also, what does "B+" refer to? And thanks for the tip about the Christmas light bulb. I've been testing with a spare injector that I can just hold up to my ear, but a light would probably be a little easier.

I'm looking around, but haven't found one yet. Anyone in Orange County, CA that can help me out? Yes, I'm getting spark and the tachometer is connected and working.

My injectors are not firing, so I've done some tests... TL;DR: Has my ECU gone bad? Tested at the ECU harness, and each injector connection reads the proper voltage when grounded. Tested at the individual injector connectors, and read the proper voltage as well. Manually fired the injectors by grounding each corresponding terminal on the ECU connector. Turned ignition to "ON" and heard each injector click. Checked the ground circuits on the ECU harness, and all were fine. Basically, wiring from ECU to injectors tested OK, and wiring from ECU to ground tested OK. I've read that ECU failures are pretty unlikely, but all evidence seems to suggest that it may be at fault. Are there any flaws in my logic, and is there anything else I should test before buying a new unit?

I'm suspecting my air flow meter has gone bad. The car is running rich and occasionally stutters at high RPM, generally past 4,000. I've looked at just about everything else that factors into setting the fuel mix but I want confirmation before replacing the AFM because it's not a cheap part and only available on a core-exchange basis from MSA. Is there anyone in Orange County, CA with a healthy AFM that I can borrow and test before I needlessly spend money? I'd reimburse you for gas costs and provide a beer or something

Yup, I've studied the FSM and the EFI manuals quite a bit over the last couple of years.

Well, I've done some more fiddling around and basically, the CSV is getting voltage when it shouldn't be. This seems to imply that it's constantly getting a start signal?

Well, I got it started again. One of the retaining nuts on the terminal block was loose. So I'm back to where I was a few days ago. It runs rich and smokes quite a bit, and if I unplug the CSV while it's running, the idle goes up to about 2000 for about 15-20 seconds and then the car starts to stumble. As far as I'm aware the CSV shouldn't even be doing anything after the first 12 seconds or something, so I don't know why this is making a difference in operation. As for revving the engine up to 5000, I didn't try that... Wouldn't the TPS enrich it even more and cause the engine to really bog down?

Logically, yes. It didn't make sense to me either but unplugging the CSV made the car run better at the time, even after warmup. I've made several rounds though the contacts with DeOxit but maybe there is something loose from when I cleaned things the other day? Between when it was running rich and not starting at all, I replaced the plugs and cleaned the contacts on the AFM, AAR, CSV, thermotime, and TPS. The problem that is causing it to not start HAS to lie somewhere in those components that I touched. Now, of those, I'm thinking the ones that can possibly cause the car to not start (in warm SoCal weather) would be the AFM or the TPS. Is this a reasonable guess?

Hmm, I'm pretty sure I didn't have the two plugs off simultaneously, but then again I can't be 100% certain they weren't reversed in the first place. I'll try testing the CSV outside of the intake manifold to see what it's doing.

Well, I verified that the sensors are plugged in correctly. I also pulled the AFM off and cleaned the contacts, checked the auxiliary air regulator just in case, replaced my blackened spark plugs and... Now it won't even start. Head, meet wall. Plugs are gapped at 1.1mm, and putting the old ones back in didn't work either.

I'll look up the pin(s) in the FSM, but I'm pretty sure I hear the injectors clicking. Besides, I'm not sure exactly how much gas the cold start injects, but wouldn't this cause the engine to run lean? I'm also unsure why the cold start is staying open. Does this mean either the cold start or thermotime is not functioning properly?

Here's my story. Sorry it's a bit long. I've had a 1978 280Z for just over two years now, and it's always been a work in progress. At first, it ran super rich. I found some of the injectors were leaking, so I replaced all of them. Then I found the cold start valve was leaking, so I replaced that too, but then discovered the thermotime switch was also bad, and was leaving the cold start open. I decided to just unplug the cold start connector as a temporary fix (before, when the valve was leaking, unplugging the connector didn't change anything). I figured as a Southern California car, it wouldn't really need it anyway. I also replaced the air flow meter, and it finally stopped smoking and ran brilliantly. I then worked on the body, brakes, and suspension, getting stuck on each but finally got it ready to take to the paint shop. I had no issues driving to the paint shop, but leaving the paint shop, the car wouldn't start. Eventually I tried plugging the disconnected cold start back in, and it started up but was running super rich again. Once home, I replaced the temperature-related bits that I'd put off: temp sensor and thermotime switch. The car has not shown any improvement. Currently, the car does not start with the cold start valve unplugged. Once started, when the connector is unplugged, the revs go up to about 2000 for about 10 seconds, and then the car stumbles and dies. This is the part that confuses me the most. To sum up, Rebuilt engine (<100 miles) Replaced parts: -injectors -cold start valve -air flow meter -thermotime switch -temperature sensor Checked: -timing (10 degrees BTDC) -fuel pressure (~35psi) -TPS contacts -thermotime/temp sensor connectors: tried switching them around, but no change Someone help!

Thanks for the compliments; I don't have any photos of the Z yet because it's still mostly stripped down, but I definitely will once it's finished. I didn't notice a hissing noise, but the thing about idle change makes sense. Are there common problem spots, assuming my new booster isn't defective? I'm guessing the pedal becoming light with the engine running seems to indicate that the main cause doesn't lie with the booster; it's only exacerbating the symptoms because it puts more force on the brake system. The parking brake comes up pretty high; I'd say to about 60 degrees? I read about the auto-adjust feature in the FSM so I will try that out later today, as well as a manual adjustment if necessary.

Well, before I replaced the MC and re-bled it, the pedal didn't quite go to the floor, and would firm up after a few pumps. Pedal felt fine immediately after bleeding, but with the engine running it goes to the floor and pumping doesn't build up resistance. I can hear the idle speed change as when I step on the brake pedal though.

Well, checked reaction disc, picked up a rebuilt MC, bench bled it, installed it, and bled the entire system (LR-RR-RF-LF), pedal felt relatively firm. Checked to make sure there were no leaks. Started up the car to induce a vacuum and now the pedal has very little resistance. Haven't taken it out for a test drive because it's dark and raining heavily, but I have a feeling it's not good. Running out of ideas...