rcb280z

Adjusted mine on my 280 and still have the same issue as "New-to-240z" is and MSA's only option to me was to heat the weatherstripping while it's on the door to "shrink" it! Yea right! I have to slam my doors, push in on it from the outside so I'm not putting too much stress on the handle to open them, etc. Mine are nearly 2 years old! Im thinking of taking it to a body shop for help. New-to-240z, if you find a solution post it here. There seems to be a few of us with this same problem and if you have installed them (MSA's brand) then you have had the same issue and adjusting hinges and strikers doesn't work.

Why not just get the one you have repaired?

Hey Tim, let me know if you want a hand rebuilding the engine.

Great info! Looking into a system for my 280z right now.

Watched a minute and half of it and had to turn it off!

Sweet rides!

Forgot about the HVAC system. Better check that first. However, I don't ever use it here on the beach. Never need any of it. I think I'll get everything ready (Diagnostic equip and tools) and the next time it "drifts" for lack of a better description I will check everything and log results. I should go ahead and run through everything tonight so I have something to compare to later....to see if there are differences.

I did have that thought.

I guess its once again time to break out the diagnostic equipment and start trouble shooting the fuel injection AGAIN! Would be nice to go more than a year without problems. So the reason I asked about the lean drift is because my Z has been running really good, great mileage and all. Was getting around 17 or 18 mpg in city and around 25 on the freeway. Anyone that lives in Southern CA knows that is good mileage. On a trip out one day recently I noticed surging on acceleration, and a rough idle. So when I got back to the house I popped the hood, its a 77 280, and looked at my fuel pressure gauge and fuel pressure is good. Checked timing, checked for vacuum leaks (pulling 18in), everything seemed fine until I pulled the plugs. They are usually a nice tan color and this time they look almost white! I'm assuming lean. So I started adjusting the bypass screw on the AFM and no change! I turned it all the way in and no change. I shut the car down and set the set screw back to where it was, I removed the cover from the AFM and loosened the screw holding the large "geared" wheel. Started the car and began inching the wheel counter clockwise and it was nearly a half turn (180 degrees) before I started noticing a change. Then it was running good. Plugs were back to normal, all seemed good until today. Now I think its running really rich! I did some running around town today and I can smell its rich now. Plus I burned through 1/4 tank of gas with a total of 35 miles. Not good. This is why I was asking about the lean drift issue. But, I don't see where anyone has had the same problem with it drifting out and then back. Which is what it seems like with mine. The only parts that haven't been replaced would be the ecu, EFI harness, dropping resisters, things you wouldn't normally have to replace. Here is what I replaced just over a year ago, the TTS, CTS, TPS, AAR, and their harness's and or connectors, injectors and injector connectors. She has been running really good until now. I have had injection issues with this car a few times now and they weren't easy ones to fix. I really haven't had the time to diagnose it this time not to mention I'm tired of having to diagnose injection problems. This was a quick run down of whats going on now. has anyone else experienced this before?

Can anyone tell me where I can find info regarding the altitude switch in the California model 280z? Nissan shows it in section EC of the FSM but with no info. I found something in section EF with very little info. Iv'e gathered it is there to lower the amount of fuel injected to decrease wear of the emission components. But only by 6%, really? Does this really affect emissions that much? Does it really have that much of an effect on our cars equipped with it? Thanks

Sent them an email.

Okay, thanks. Will check them next.

SteveJ, I tried them first. No luck.

bryand2 I'm glad to see it worked for you also.

So running 0.006/0.008 is a bad thing on an original L28? Sorry if this is a stupid question, just bare with me. I have been wanting to do this for some time now on my 77 280. Valve train is really noisy (to me) that is. I have never done the HOT adjustment, always cold (0.008/0.010). And I do it twice a year or more just because... Have had 2 Datsun mechanics tell me they do it cold as well.

Hey Tim, sweet Z! We ought to get together some time. I'm In Oxnard.

My L28 in my 77 280 also makes noise like that after warm up. Has always.

I still say putting a potentiometer inline is not "a fix" rather a mask to cover the problem. No different than making adjustments to the AFM IMHO. The problem is still there.

That's why I posted the question. I'm no electrician but I didn't think it was possible. Interesting Powerglide...that you would say fuel type related. Never gave it any thought. Why would it have been all of a sudden. My curiosity is up now about fuel additives is SoCal. Didn't think it got cold enough for it. As far as fuel delivery, no problem there. Observed no change in fuel pressure at all. I can see my inline gauge under the hood scope from inside the car.

Yes I am speaking of FastWomens lean mixture drift. My 77 is running similar to siteunseen's did but I was under the impression that it only happens with the 78 model. I haven't had a chance to trouble shoot anything yet. Has anyone experienced the same thing with a bad altitude switch which is a CA only sensor, supposedly. Damn, everything had been replaced when I was putting it back together a year ago. CTS, TTS, and harness to those, injectors (new) and connectors, TPS, AAR, CSV, Iv'e had all these new parts for quit some time and when I was installing my header I went ahead and replaced these items. Oh and a refurbished AFM. I swapped my old one in and it ran like crap also so I put the rebuilt one back on with the new setting and it runs good. So Far mileage hasn't gotten any worse either, plugs look good. I could keep on and on but I don't want to do that yet and waste peoples time here. It seems to have had the symptoms of "lean mixture drift". And I wanted to know what the symptoms are. Thanks

Wow! looking sweet! Im jealous, wish mine looked as good.

Okay, before I go into detail of my new F.I. issue I'm posting a question: Anyone with the so called "ecu float" issue, can you describe symptom(s) or reason(s) you believe that is what's happening.

ksbeta, are you selling these? I think one would look good in my 280 :-) I have always wanted one but usually can't touch them due to price. More info on the block in the shop.

Hmm, wonder if this will work my polished valve cover.

I'm with you Willoughby. I just responded to a recent thread regarding the same thing and I also have done the same things you have to attempt solving the problem. I recently adjusted (slight) the AFM richer and my problem went away, so far. But I'm not sure if that is a fix or if it is just masking the problem. Only time will tell. Like bryand2, my 77 would do the same thing and it is annoying! Fires right up in the morning, warms up normal, runs great. When it would do this (run like crap) after sitting for 10-15 min I was on the hunt for the problem and never found one. That's when I decided to richen the AFM one full turn of the bypass screw. That was about 2 months ago and I haven't had the issue since then. Again, I'm not saying it will fix it but it seems to have corrected mine. Good luck and post your success when it happens.