bryand2

I think I may have just answered my own question, if it stumbles but starts in cold weather, but wont warm start at all when the outside temp. is warm, possible faulty air temp. sensor?

One thing I should mention, I am in northern california and we are still having 40-50 degree weather and my car is doing this, I am trying to get this figured out before it gets warm, once that happens the car will not restart at all when warm.

Thank you for all the responses guys, I am fully aware that this is a common issue, especially with 77 and 78's. That being said I have spent the past 2 months reading every single forum post I could find on this issue and trying different anecdotal things that worked for different people. I have tested fuel pressure both with the car running and after shut down, pressure holds fine between 32-26 psi. New plugs, wires, cap, rotor. One thing that I should mention is that unlike many of you guys, I bought this car 2 years ago from an old lady who had invested $25,000 in this car. She spent roughly $12,000 on the engine rebuild alone, I know that sounds expensive but she had almost every wire, sensor, relay, hose replaced, on top of fuel injectors, fuel pump, valves and valve spring, pistons, connecting rods way too much work too list. This work was done in 2003. Since then i changed the thermostat and while I was in there, checked the WTS, Thermotime switch and gauge sensor, all three sensors were in perfect shape, still looked like new brass actually. To willoughby you are correct, it only happens when i turn the car off and leave it for 10-15 minutes. Now on to the testing ive done,, checked spark at cap, coil and wires, checked fuel pressure and its in spec, checked the injectors with a noid light, they are ok. As far as vapor lock, I understand that it is potentially possible for it to happen, albeit unlikely on FI, but when the car is doing this and the engine is hot, the fuel rails are the only thing in the engine that are actually cool to the touch. One more strange note, as soon as I start driving the car and the engine speed reaches 2,000 rpm it disapears...

Ok guysm I'm at my wits end trying to figure this out, I have searched here, hybridz, and zcar.com. Several people with hot start issues, several different fixes for each of them, none of which have worked for me. The car starts an runs fantastically,no hesitation, no backfires, no smoke, nothing. When the car is run on the freeway or allowed to get up to operating temperature then turned off, after sitting for 10-15 minutes it will start, but runs on 4-5 cylinders. As soon as the car starts moving and the rpm's reach 2,000, it goes away instantly. Checked the WTS, Thermotime and cold start are disconnected, all fusible link, relays including FI and power relay are good. I know its not vapor lock because the fuel lines are cool to the touch. Any suggestions other than fuel pressure or the fuel pump check valve? those have been checked already

Ok so the new plugs took care of the problem for the first 2 days but it started misifiring again today when warm. I thought maybe it was the water temp sensor but I dont understand how that would cause a misfire. The other thing that is stumping me is that as soon as the car is under load and moving it goes away. Injector possibly sticking?

I also noticed there was a small amount of oil on plugs

I am using ngk plugs, the old plugs were ngk bpr6es, the new ones were ngk bpr6es-11, which are pre gapped at .044. I did put them back in the correct firing order, and no I did not damage the plug wires. I pulled the new plugs and the tips were white so i thought maybe the -11 gap was too big. Replaced them with the bpr6es and seems to have taken care of the misfire when warm for now...

Hey guys I have a strange issue with my 77, its bone stock and was running fine until i changed the spark plugs, now, when the car is warm and i turn it off then restart it, its only firing on 5 cylinders while idling, as soon as the car is moving and under load it goes away. The car does not do this when cold, but i pulled the plugs and it is running very lean, any ideas?

Ok sorry dont mean to thread jack here, but I have a mystery sensor on my thermostat housing on my 77. If you are looking at the thermo housing from the nose of the car, it would be the sensor on the top right, or if from the drivers side it would be the top one closest to you. The FSM just shows this as a plug, but I have a brass plug with a SINGLE wire coming off of it. The wire has a bullet connector on the other end that is not connected to anything just dangling there. I have searched as many posts and google images and manuals as I can find but I am stumped any ideas?

Hey guys I know this thread is a bit old but I just recently discovered that the PO of my 77 did the 60 amp alternator swap from a zx, and it was wired incorrectly. I rewired correctly and car ran fine for first couple months now every time I start the car it has to be jump started. Not sure if its the battery or alternator but the volt meter is reading about 13 volts with the car off. here is the strange part, I disconnected both of the relays under the passenger seat but for some reason the brake warning lamp and volt meter light still come on while key is in on position like theyre supposed to and turn off after the car is running, any thoughts?

Ok so I rewired the alternator according to the atlantic z car write up, the charge light and brake warning lamp test now work just fine, but for some reason now my idle is always too high, like 1500 rpm, I dont think this should be related to my re wiring the alternator but none the less its happening, and if i adjust the idle down with the idle screw, after the car cools off the idle is now way too low, any ideas?

Hey guys, I just discovered that one of the previous owners swapped out the alternator for the 60 amp 280zx alternator. I read the atlantic z car write up on how to wire it, and whoever wired this did it completely different. They connected wires 5 and 6. The car runs but the voltage drops when lights are on, heater is on, flashers are on or the radio is on. I also noticed the brake warning lamp relay under the passenger seat is disconnected because it the brake lamp stays on permanently when its plugged in. Does having that relay unplugged have a negative affect on anything else and how is the car running with only wires 5 and 6 connected? http://atlanticz.ca/zclub/techtips/alternatorswap/index.html

I have a set for sale, let me know if your interested

hey guys i have a 76 that is now smog exempt, i wann start pulling emissions stuff off to clean up the engine bay a nit, any suggestions on where to start and what i can and can't pull would be appreciated

why what happens when turning intospped bumps and driveways?

does anyone know f the steering coupler bushing can be replaced by just loosening the 4 bolts on it, or does the column need to be removed?

does anyone know is the steering coupler bushing can be replaced without removing the steering rack assembly, it looks like it can because its 4 bolts that go through the bushing, but i dont wanna attempt it and screw something up

ok guys i have a 76 280z and i have the FSM, but cant seem to find a section where it gives help on changing the belts, can anyone help me i need to change all my belts, except timing chain

fastwoman i would def recommend you add some lucas oil stabilizer to the oil in your diff and transmission, especially in cars this old, that stuff is amazing

can someone tell me were to find the drain and fill plug for the transmission and the drain/fill plug on the diferential on a 280z? i have the FSM but no where does it seem to say where these plugs are?