zewald

Zed, i don't think it's the timing since it idles perfectly. though i could be wrong. i have checked the breaker plate, and it looks fine. it is indeed a manual transmission. i haven't tried to full throttle it, but i will tomorrow and let you know. FastWoman, i don't think there's a rip in the boot, but i can easily get one to see if that has any affect. and i'm not exactly sure how to check the fuel pressure. maybe this is a dumb question, but my fuel damper is pretty much wide open, could that be effecting it?

hey guys so i just recently got my 75 280Z up and running, and actually drove it around some, needless to say, i'm stoked. the only problem is that the engine backfires any time i try to give it more than a little gas. if i press on the gas slightly, to allow the rpm's to creep up, it's fine, but any time i step on the gas with any real force, the engine sputters, backfires, and loses power. I've checked all my vacuum hoses, and there are no leaks. any idea what the problem could be? thanks in advance, Zach

as far as what manuals to buy, i would definitely steer clear of the haynes manual, i have a 75, and the book only has a supplemental chapter pertaining to 280's it was really a let down.

Alright, after installing the new throttle valve switch, replacing the contacts on the cold start valve and the air flow regulator, and fixing some broken wires... IT WORKS!!! you guys have been great, and honestly, even with help from my step dad (who used to work as a mechanic) i would not have been able to figure it out. Thank you SOO much. the car is running, and after about 10 seconds of holding my breath, waiting for it to start clanking and shaking and blow up, it didn't. the engine sounds great. i think that's about it on this thread for me. i'll probably transfer over to the "what i did today" forum. hope to see you there thanks again

ok, so after checking every circuit that runs through the control unit, it looks like everything but the air flow regulator circuit is good. also, i took the fuel pump relay off and tested continuity (based on the FSM) and that seems to be shot. I was under the assumption that it was functioning regularly because when i turned the ignition to "start" it clicked once. apparently it should click repeatedly? i'll see if i can get a mechanic friend of mine to get me a good deal on one, and keep you guys posted. also, at pick a part i found a throttle valve switch and a motorized antenna, i'm happy about that. hope the relay and air flow regulator fix my problem. thanks for all the ideas guys. on a side note, when i turn the car ON, my catalyzer lamp comes on, should that happen? i'm actually still confused on what that actually indicates.

Hey guys. I'm Zach. i've been in love with Z's since i was, oh, let's see, 10. a neighbor had a silver one that in retrospect was probably stock, but i thought it was a car from the future!!! i loved that thing. i'd chase after it every time he drove by. i loved the sound and the way it looked. So this january, i bought a 75 280Z from a guy for $600. it was a HELL of a deal and sometimes i feel kinda bad about it, but then i kick myself back to reality and thank God for what i got. it's not running yet, (and those who've seen my other post know why) but when it's all said and done, i'll have a black/grey/green interior and a 240 green paint job. i'm hoping to replace the exhaust system and sub in a cherry bomb muffler, man i love those things. oh, my grandfather has been carving and working hardwoods for nearly 40 years, and so some of the interior panels will be replaced with maple stained and varnished an opaque green. i'm seriously excited about this project, and although i'm expecting it to take a good 5-10 years, any suggestions and comments are greatly appreciated. I can already tell this is a great group of people, and i hope to meet some of you on the road to admire each other's work. Cheers, Zach

ya, checked that too, i sent compressed air through the whole line.

you guys, and girls of course, thanks fast woman, have been great, thank you. i think friday is the next day i'll have enough time to do anything, so i'll let you know how it goes.

right next to CSUN. off the 405

19-20 is great guys, remember, i said i have a truck. haha. i get 16 on average. any savings helps. I've tried depressing the flap of the AFM, but nothing happens. actually, i have the fuel line disconnected from the intake manifold, because i just want to see if the pump will fill the line and make it overflow (into an empty coke bottle) does that have anything to do with it? will it not pump if the manifold isn't registering fuel or air movement? Zed, yes, i've done that, and thanks for all the info. the pump doesn't run. i'm getting very discouraged. BTW, at O'reilley auto, the combined relay is around $140 but at nissan genuine parts, it's only about $80 at least that's what my research has found: just a quick fyi. I've checked the relay and it clicks just fine, how would a faulty fuel tank sensor effect anything? i think mine might be faulty.

that's great man, thanks. hope it works. with gas prices the way they are, i need to start driving the thing so i get better gas mileage than in my truck, haha.

i checked with a volt meter. and the engine does spark, it's run for as long as 30 seconds on starter fluid. where is the fusible link for the fuel pump? i've checked the fuse box and replaced blown fuses, tested the fuel relay, the control unit, and will check the AFM tomorrow. thanks for replying by the way. both Zed Head and BrianL1987

i don't have a test light. where could i find one? and the problem is that even when cranking the engine, the fuel pump gets no power. i've checked all the grounds and gotten rid of all the corrosion i could find, so i just don't know what to do next.

Hey guys, i have a 75 280z, and it's taken me about 2 months of spinning my wheels to finally get on here and ask about this problem. I've looked at everything i can think of in the car. my fuel pump will not pump gas into the engine, it's not getting any power. i've checked the connections, and gone through as much of the harness as i can get to at the moment. and i haven't been able to find any problems, i replaced the pump to no avail. (i tested the old one and it definitely was faulty anyway) but i was wondering what else i should check to find the problem. this car has been my dream car for a long time, and i really want to get the thing up and running. any help would be appreciated.