ll77

I have a 76 280z that runs rough, lacks power, and is quite gas-inefficient. I checked my air temp sensor and water temp sensor w/ a multimeter, and they read acceptably. I hooked up a vacuum gauge with a T at the FPR vac line, and these were the results: ~10.5 in Hg @ 800 rpm (not jumpy, but twitchy) (I don't have a tachometer yet, sorry) drops to ~4.5 in as throttle is applied raises back to ~10 in to WOT up to ~20 in @ throttle release Fuel pressure (gauge is not very accurate) 39 psi (idle)- 42/43 psi (throttle applied) I tried messing with the AFM (PO put wrong one on the car)- gave it more fuel while also decreasing idle back to 800 rpm (my dad was screaming the tach reading to me over the exhaust hahaha) and my vacuum started drifting steadily between 15-17 inches, which would be more acceptable. I don't have any big irregularities except for the fact that the vacuum is SO LOW, and I understand that is causing my very high fuel pressure. I checked my valve timing, I cranked the crank pulley till the timing mark was at 0 deg BTDC, so TDC. Weird side note: my intake/exhaust cam lobes were making 11:15, if the intake were the hour hand and exhaust was the minute hand (relative to timing chain). Also the dizzy was pointing underneath the upper radiator hose, looked as if it were already touching the #1 plug wire contact. That don't seem right. So anyways, I looked to the marks on the cam sprocket, and the triangle was waaaay to the EDIT**right of the mark. So I'm too advanced, I wonder how that happened. Then I decided to look at my PCV valve, so I popped off the hose under the BCDD going to the intake manifold, nothing there! Just a bunch of carbon. Whaatt? I need a PCV valve. SOO, I've gathered I need to adjust my valve timing, and the right model AFM would help too, yeah? What do you guys gather from this? Thanks a bunch for any input!

Sorry, I don't want a rebuilt/ remanufactured one. I would prefer one from JECS, but I am flexible on that.

Yes, I would like pictures of it, and also of the sticker on it please, thank you.

Thanks for all the advice guys, I'll be doing some new tests today. I've realized it is slow to warm up.. hmmm. Zentech and Nash, I've emailed and PM'd.

Oh yeah that's what I meant, but the previous owner got it from MSA. I've read so on the internet.

HC and NOx were well within limits, CO was through the roof, Co2 was 11.9% @ 15 mph and 12.2% @ 25 mph I have no clue where the original one is, and I have no clue why the PO would swap in the wrong one for it. My worst fear is if I get one and it doesn't fix the problem. Strange thing is, it passed with flying colors 9 yrs ago, back when it was still an automatic..

Fuel pressure seemed to be a little high, I replaced the pressure regulator and there were no kinks or clogs. Fuel pump had been replaced a while back, so my conclusion was the gauge was off a bit haha. So I did all that just for good measure I guess. TPS was professionally adjusted, although I can't hear a difference with it disconnected. I went through the EFI manual circuit tests, everything ok. I went to a CA gold shield certified station and they said my AFM wasn't doing its job right, so I am convinced it's the AFM. I have adjusted the wheel to the leaner side, and it did feel better, but it still wasn't passing. Also, mine is one of those rebuilt MSA ones and all I've heard is that those are bad news. But thanks for the link. If anyone has one, please let me know.

My car will not pass smog, and runs rough. It is running very rich, and gas mileage is quite poor. My AFM part no. is a31-626-000, which MSA says is for a 78.

Hi everyone, I have a mismatched AFM and I'm in the market for the right one. MSA tells me the right one for 76 is part no. a31-060-001 But I'm nervous that the ECU could have been swapped too, since the PO messed around a lot. So if you can offer insight into which AFM will function properly with ECU part no. a11-600-000, please do and I'd appreciate it. If not, then I'm looking for a31-060-001 please, thank you. EDIT: Part no. has been confirmed to be a match. Thanks newzed. Oh yes, and please NO REBUILT AFM's.

Yeah so I finally got some crappy pics How it looked: This is the old seal, the orange stuff is rtv Front (engine side) Rear (drive shaft side) I thought it was cool that it had a metal band inside to snug it on the shaft it took me a week and a half to get it right, I didn't want to use to much rtv, but it kept leaking. It still leaks, but within a tolerable amount. I guess it will stay that way until I can fix the transmission So my teacher says that I may be able to replace the tail shaft quite easily, way he told me it sounded like a bolt on process. And it looks as though it could be pretty easy with the driveshaft and shifter off. Any words on this?

Hi guys My transmission has been leaking from the rear so I dropped my driveshaft to change the rear seal. There was a shitload of rtv on the seal, and when I cleared all the rtv, I saw that the metal part that holds the seal on the transmission is severely chipped. What is this called, and is it easily replaceable? The transmission is in the car right now. Thanks.

sounds reasonable. but i have to go to work now ttyl.

I don't think the 260 one fits.. haha noooo why'd you throw it away mann? Could've given it to mee!

Ok yeah let me know. So it won't come w/ a muffler?

I am looking for a complete stock 280z exhaust below the manifold to the muffler (not including manifold). I want it shipped, unless you live really close to me (Alameda CA 94501). PM me if you have anything. Thank you!

Oops forgot to check the thread. Sorry Tony, I don't know what and RX1 scale is. Correct me if I'm wrong, but is the TPS inside the black box on the side of the throttle body? Yeah, so I definitely have the wrong afm, the vendor told me so too. Today, I made the adjustment for less fuel (since it's running rich) and maybe I'm mistaken, but the throttle seems snappier. I also advanced the igntion timing to 12 BTDC, b/c I heard that advancing would give the mixture more time to burn. The car dies after a bit when I disconnect the afm. So I guess the afm is OK. I will begin researching the TPS. Thank you everyone!

Thanks Tony. But what do you mean by what does it do over 3500? Scratch the part about it not revving past 4k, it's actually fine, just takes longer than I expected it to. A bit sluggish on the throttle response. And I am using a analog ohmmeter, and there is only one setting on it, "x1k." I am not very good w/ electrical know how, I can only do whatever manuals tell me to do.

So today I put on the afm w/ the connector off to see if it was actually working or not. It started up, but would die immediately. I plugged in the connector, and it started right up. So I guess the afm is working. However, I'm thinking that it is not a 280z afm, because I noticed that the holes on the bottom of the afm did not match up with the holes in the mounting bracket. I also think that 75-76 models had a blowback valve in the flap of the afm, and mine does not. So, I'm thinking that the previous owner tried to use a 280zx afm on my car. Do you guys think this adds up? would using a zx afm in a z explain the problems I'm having right now? Pics coming soon!

Oh ok sorry, I'm just so used to it. But thanks for the tip, I'll be sure capitalize in all my posts from now on. But yes, I did also perform those tests. I can't remember off the top of my head what the results were, but they were unsatisfactory. They did not read 180/ 100 ohms like they should have. The gauge is located after the fuel filter, before the fuel rail, so the reading should be accurate if the gauge is ok? Thanks for the help!

hey guys. so ive been having smog problems recently. i got a tip from a smog station that my afm might be the problem b/c its running lean at idle and very high on CO at speeds above idle. so i took the afm and ran some tests w/ an ohmmeter and it failed both potentiometer tests. these 2 were from the fsm when i ran this test (as seen on http://www.atlanticz...fm/index.html): Measure the resistance across pins 7 and 8 while moving the flap. It should change. (though it may be jumpy) Repeat this but between pins 6 and 7 while moving the flap. the resistance only dropped a little bit when i began pushin the flap back, but stopped dropping about a quarter of the way in. resistance went from continuty to approx. 0.4 ohms. it checked out on the rest of the tests. my mechanic friend tells me he doesnt trust ohmmeter tests b/c he's seen parts that fail resistance tests work fine, but I was thinking it would make sense that the potentiometer was bad b/c that could make the flap open, but not all the way. so at low engine speeds, it could get too much air, making it lean, and at higher speeds, too little, making it rich. is that good logic? also, it seems my car will not rev past 3500-4000 rpm, and its got a rough idle. perhaps related? also, any ideas of what else could be causing my car to run rich would be helpful. the technician mentioned a couple things, but i didnt write them down ( i know, i should have). i think he said my cold start valve shouldnt be the problem, i didnt understand why. also, my fuel pressure is registering about 40-41 psi at idle, and jumps to about 43 when i rev it, and i know that the fuel pressure should be at about 36 psi. so im thinking about the fuel pressure regulator too. could also be that the gauge is faulty or inaccurate, it is installed on the fuel feed line, but i have heard that this doesnt indicate the "true" fuel pressure as that should be measured from the fuel rail? also, i am in the market for an afm, and i might make a trip to see a guy with a couple of them tomorrow. he has 2 280zx afms, but only 1 280z afm, all used, not tested yet and have been tweaked for air/fuel ratio adjustment. so i was wondering do 280zx afms work in 280z's too? i know they both have l28's so they should right? but if not, i think i'll go for a remanufactured one instead off zccjdm.com. so what do you guys think??? thank you soo much!!

hey guys, I finally took pics..

whoops sorry about the double post, but I'll get on those pictures as soon as I can get my hands on a camera. Thanks guys.

Thank you m4x, but I dont see any screws or anything when I look at the mirror. i know from my new mirrors that there should be screws, but there are none on my current mirror. it looks similar to a california style mirror. btw come to think of it, did those come stock on CA models? I live in California. And are you saying that it would be a good idea to remove the door panel first when I get started on it?

Hi everybody. I'm fairly new to the site and I just bought a 280z a couple weeks ago. It only came with the drivers mirror, so I just bought a pair, and I'm going to install them soon. Can someone please tell me how to remove the driver side mirror? I looked in the manual and there's no detailed info on it. I see what looks like a plastic cover behind a piece where the actual mirror is located. I am guessing that the screw is located here, but I dont know how to remove it. I've been prying at it with a screwdriver, but I don't want to break anything. Do I have to remove the interior trim to get to it? I apologize if this has been covered before, and for my ignorance. I'm still learning! Thanks in advance