DuoWing

Normally this sort of thing I'd just opt to do some kind of undercoating. Ever since I got into the trying the rolling on rustoleum thing it's got me a bit more gung ho about painting stuff. Especially now that I've seen how easy it can be done. I think another fact is that the car is in such great shape to begin with, I want to keep it that way and maintain it as best as I can.

Alright I managed to get my marks on the timing cover and the crank pulley marked with some white out. For my 87 the hood label and FSM show to set it at 15* before TDC. Anyway I was wondering how do you guys feel about timing, I know with the L28ET people usually say Nissan was pretty conservative on the factory timing and you can advance it, get more power, and still be gold. I was wondering if it was the same for the VG30ET or not. Like would going to 20* BTDC be dangerous or not? I know the 84-86 Z31Ts ran 20, I figure there must be some reason Nissan retarded it 5* for the 87 model year.

These cars will run with the AFM disconnected? One time when I replaced my radiator, I disconnected the AFM and removed it to get to one of the radiator mounting bolts better. I got everything back together and the car would crank and crank, but would not start. I eventually found out I hadn't plugged the AFM back in. I was initially going to say maybe the ignition itself is shot. That was the only thing you didn't change, but you have blue spark up at the plugs so I'd say you're probably ok on that end. One thing you need to do is a fuel pressure test. If the fuel pressure regulator failed, it could be stuck open allowing all the fuel to go straight through to the return line and not actually build up enough pressure in the rail. You should also hook up a multimeter to the injector connectors and have someone crank the car while checking to see if a signal is getting to the injectors. Also as said, check your water temp sensor. These always go bad. They're just old and it's about their time. Anything that is small has a thermistor and is constantly heating and cooling is bound to fail after 30+ years.

Yeah, the ECU's do have this same thing. I forget if it operates as you said, but the procedure for telling if your O2 sensor is good or not is by checking that light. While revving or holding the RPMs up the light is supposed to blink on and off which would indicate an O2 properly cycling back and forth. When I messed up my O2 sensor from it getting banged around in the turbo's downpipe when I removed my manifolds, I checked that light and it was just constantly lit up. The car also ran noticeably more sluggish.

Well, either way it's rustoleum'd over. Tough stuff, and gives me more peace of mind knowing that there's paint over it to help keep the metal better protected.

If the car runs good all around I'd say your CHTS is fine. I'd definitely check your O2 sensor, there's a good chance it's never been replaced or even if it has. It's probably dead.

One other thing I just noticed, comparing the pics of my wheel well to others. It looks like that hole in the bottom of the wheel well, normally has some kind of rubber plug, where I didn't have one in mine. I'd imagine not having it would be alot better off in the event that water gets in there, which it may very well be doing, but it may drain out and be why it's in alright shape. I also noticed there was a hole on the other side that looks like it's meant to be a drain hole for under the tool kit, except that there was no real way for the water to get to it. It's like Nissan designed it to help get the water out, then covered up those spots. Anyway here's after 2 coats, I'm going to throw a 3rd, maybe a 4th coat, just to really make sure it's all covered up and sealed up there. After doing some searching, I found alot of people split on Rust Bullet and POR-15. Well I've used por, but alot of people seem to like the Rust Bullet. I figured I'll get some of that and that fiberglass mat and use it to seal up the couple of little holes I've come across under the tool kit. Since it's not structural I figured this would be alot easier to do.

One thing I can't figure out and that kind of bothered me about the spare tire well. If you notice there's alot of silvery areas where it looks like the paint has come away. I have no idea why this is. Either way I pulled the spare tire back out, wiped it all up, got out some rustoleum and started painting the spare tire well just to be safe. I'd have used por, but I'm all out.

Alright, I've finally finished cleaning up that area of rust and crap. I scraped off a bunch of junk, found a few small holes, and por-15'd over the whole thing. Painted the new piece of metal with rustoleum. So there will be a little bit of metal that needs patched still, but not much. Everything was going well, until I broke part of the hatch/fuel door release cable. The plastic that holds it to the arm... I used some zip ties to hold it together. It works at least. Need to go cut off the ends. Here's a few shots of the other big rust prone area the spare wheel well. Underside of spare well: And for the heck of it, how my hatch currently looks...

I started with a Z31. I got it for free, was rusted to crap, driver's door didn't open easily as the fender was bent in, etc. I learned how to do a lot with that car and I just loved it. It's super 80s in it's design and in my opinion is part of the reason why the Z31s especially the 84-86 models are looked down upon. I still love them though. After really getting into the 280ZX I really felt like that was the hated generation. As it was a car that was stuck being the last of the L6 engines, using a similar styling as the S30s, but then trying to become it's own more luxurious GT where the Z31 carried a whole new base. In the end I've come to love the S130 and Z31 generations. I think having a Z31 as my first car really helped, but they're super nice. Great cruisers, still somewhat easy to work on. Not bad fuel mileage, and if you have a turbo they've definitely got some go.

I figure even though the other side isn't leaking, I might as well do the seal anyway. It's good that it's not a structural thing. Although at some point I plan to get the few holes cut out and have new metal welded in, just for the whole peace of mind thing.

I don't know if it's something Nissan put on, or something the previous owner put on or what, but there is a ton of gunk and crap. It almost seems like a soft metal or something that sits over the base metal for the hatch. Anyway I've gotten half the area cleaned up and painted. The lower hole that looks like it could pass as an extra large drain hole, was so far the only spot where I was able to punch a screwdriver all the way through. I think if the second half goes this well, I'm in pretty good shape.

Yeah, that's really the only spot. It looks even worse thanks to the wet flaking off tool kit, but I've been going over the car and it looks real clean elsewhere. Like I said spare tire well is super clean, inside driver's fender etc is all real clean which is right by that spot. The carpet was only wet in that area. Like I said the underside is in really good shape. There are spots where some of the undercoating has come off near the front where the frame rails attach up front, and it's all really clean, not rusted or anything. My biggest thing I was wondering, is that a separate piece of metal that looks like it's held down by 5 different screws? Update: I'm feeling better about this as I work with it. I've been pounding the flathead more and more and not finding many areas that punch through. Alot of this is still really solid. Even the rust where it's flaked apart and pulls up, it's really hard to break off. I was looking at my 280ZX in the hatch and if the design is similar it looks like a big piece of metal across the hatch, with some more pieces over that, and then the 300 looks almost like it may have another piece layed over that where the trunk/fuel release cable arm is attached. It also looks like a few layers of metal as I pull up and sand away at this mess.

Alright guys, I'm a proud owner of a 1987' 300ZX Turbo 5-speed. I love the car, interior is in amazing shape, the paint is in great shape, engine bay is super clean, the body is really clean. New brakes, tires, tokcio adjustable, eibach springs, previous owner even showed me how he had the common 300ZX manifold crack fixed. The car is nearly rust free, or so I thought. Underside is in incredible shape as the car came from the Carolinas, checked the spare wheel well and it's super clean. I noticed this today when I lifted up the carpeting to look at the tool kit. Carpeting was wet and tool kit looked a little rusty. I pull it up and see everything looks like it's been POR-15'd over. Theres a hole going through the back panel, and it's all been covered with POR. it's fairly clean around the hole. The driver's inner fender and everything is super clean and there's no sign of rust. It's just this spot. I even then pulled up more of the matting and carpeting and notice towards the middle and over to the passenger side was hit with por, but it's not rusty. Anyway is there an extra panel or something that was added over the existing metal where they then attached the arm for the hood/fuel door release? I started jabbing around with a flat head and there were spots where it went through, but hit metal underneath. I was scraping rust off with the flathead and like I said looked like another layer underneath this? It was kind of oxidized, but alot more solid and I was thinking I could get as most of this rusted over metal pulled off, sand down the remainder to bare and POR-15 that. What's your guys opinion on this? I don't know how to weld, but I know people who know how to weld. I started pulling up other things and everywhere else inside the car is clean. Just this one bad spot. So advice on what to do, would be appreciated. I guess the first priority would be to start sanding like mad and see what's left.

I've never really heard of many people having their intake manifold gasket leak, just the exhaust side of the gasket. Although I guarantee it happens. Try using the little attachment for the can, that little straw thing to help direct the spray so you can get it right around the injectors to help narrow the issue down. If the injectors were replaced and the o-rings weren't you may have leaking o-rings.

I'm assuming he meant the exhaust manifold gasket as well. Since he said it sounds like a propeller plane. When my exhaust manifold gasket was leaking, I always described it as a ticking that sounded like a Harley or something. Is the car a turbo? If your EGR tube is broken that will affect it. Basically the car will start and idle smoothly because the BCDD or VCM depending on car prevents the EGR from opening. Then once you start to rev it, the thing will allow the EGR to open and start causing a huge vacuum leak. Try removing the vacuum line from the EGR valve on the manifold and just plugging that line off, and see if that helps. The leaking manifold gasket I don't think makes too much difference. Or at least it didn't make much difference on my leaking or fixed. It still ran the same for me, but I was happy knowing that it and the broken stud were fixed.

Nissan's parts section know very little about the Zs. They have a hard time finding parts, and then they mix up part names, and think they know more about my Z than I do. You pretty much need to go in with a really good description, diagram, or straight up part number. At least that's the way it is around here. I've wanted to do the conversion myself.

There's still alot of stuff I'm not sure about, but if you've got a cheapo water pump, I'd wager that it could cause issues. Maybe not provide enough pressure to circulate the coolant as well as it should? I've been lucky enough to not have to deal with overheating issues on my 280ZXT, but my old 300ZX had overheating issues which turned out to be the radiator. Ended up replacing hoses, thermostat, radiator, and water pump trying to fix it.

Not too sound like a smart ass, but right off the bat I knew it was a late model ZX. He said digital dash , and I think the digital dash showed up for the 83' models, maybe the late 82's. Anyway do not rule out the CHTS just because it was changed. This was a horrible issue on my ZXT. The previous owner was having all kinds of problems, he changed the CHTS and it still was doing the same problem. Turned out the new CHTS was bad. I eventually swapped it over for a CHTS that I pulled from my old 2+2 which was running perfectly. Oddly enough that one was on it's way out. Finally I got a brand new CHTS from motorsport, it was still in the Nissan packaging. With all 3 sensors sitting on a bench in the open air. They all read differently. The new Nissan sensor read quite a bit different from the other 2. This was what finally fixed my problem. Is your fuel pressure regulator functioning? Depending on how it fails it can richen up your mixture as well. Also check your air regulator, if that thing doesn't work your car will be getting a lot less air on startup. You have the AAC which helps to compensate, but you still need the air regulator for that extra air. Finally a dead O2 will really leave you hanging. With no O2 or a dead O2 my car was really sluggish and really had no go under 2000-something RPM. Once it got above that certain RPM everything was great, but below that was torture. Pulling out into traffic was terrifying as the car felt so slow to respond.

Are you losing coolant though? I wouldn't suspect the headgasket unless you're smoking or finding coolant in oil or vice versa.

Have you removed the kick panel on the driver's side to uncover the ECU? Unplug the ECU harness connectors and plug them back in. While driving if the problem happens try shaking the wires. I had a problem for a while where the car would run fine as long as I drove with light throttle and kept the RPMs under I believe 3000 or 3500 it was something along that. Anything over the car would start to lose power, and it would struggle to make it to the higher RPMS, below it was fine. Under hard throttle/boost it would start popping. Just like you're saying. I found that when this would happen I could reach down and give the ECU wiring a good shake and then the car would start running as if nothing ever happened. The car would run good for a while then all of a sudden act up again. I removed the grounds from the intake manifold cleaned them up, and then tightened them back down. This seemed to fix the problem for a long time, eventually it showed up again. Nismopick clued me in on what seems to be the issue. It's the 2 ground wires that come out of the ECU. They go into a crush connector that connects to 3 other wires that becomes the main ECU grounds. I cut this out and redid the connections and I've never had problems again. Things even seemed to run smoother.

I think they mean RHD car?? That luckily doesn't look too bad as far as rust issues go. You could be much worse off.

I have an 83' 280ZXT. I bought 2 years ago as of 6/4/08. Paid $1500. Car had an alright body, a decent interior, and an 89k mile L28ET with P90a head. The engine was the real reason I got it. Car ran like crap, and it was a pretty nerve racking 2 hour drive to get it back home. Car needed a new ignition module, CHTS, and an O2 sensor. Over time I did a bunch of stuff to it. Car now runs like a champ and only has 94500 miles on the engine. I used it as a daily driver, I was surprised at how well these things keep going. In 0 degree temperatures the car would fire up with no hesitation, keep driving with no issues in that temperature, on a 2.5 hour drive back home through a snow storm. Then keep on going. All in all I have come to love the 280ZX. It's probably my favorite of the Zs.

One last update until I get it finished. Anyway I got ahold of an 86' 300ZXT ECU. I haven't gone for a good test drive or anything, as I need to get a bung/nut welded on so I can use the titania O2 sensor, but I connected the ECU up. Car fired right up and revved well, I also noticed that now my fuel pump works as it should the 2-3 second prime then shuts off instead of staying running. So this should finally correct everything.

I have mixed feelings about the Z31. I love it, but I love the S30-S130s more. My first Z was a rusty old 85' 300ZX N/A. I eventually bought a 280ZX 2+2, then got a 280ZXT. I've been looking for an S30, but I saw there were a couple Z31s for sale, went to check out one. Started missing my old Z31 now I'm planning to buy me an 87' ZXT 5-speed.