Technical Questions & Answers

I am in the process of rebuilding my AC system on my 1990 twin turbo Z. Rebuilt compressor, new drier, new expansion valve, new pressure sensor, and changed all o rings. I vacuum tested the system and everything looked good. When filling the the system with R134, I discovered, that the sight glass was leaking. I was able to get the sight glass out, but it got damaged during the process. I can't tell what kind of seal was in place below the sight glass and have not been able to find any information on it. I have two questions: 1. Does anyone know where I can find a replacement sight glass or what other car has the same sight glass that I can get it off of? 2. What seal sho…

Hey guys, So yesterday, went to take out the Zed for a sunset drive, to be stopped in my tracks with it not starting. I realised through the horrible grinding type noise from the starter motor that there wasnt enough juice in the battery to crank. This morning, I've borrowed a mates jump pack. This is now where I'm confused. The car cranks with the jump pack, but no start? I thought maybe it wasnt getting fuel to pressed on the accelerator and I can smell fuel (not sure if this is relevant). No matter what, it wont start. I'm going to get a new battery anyway as this one is clearly knackered, maybe that will fix it - Does anyone have any idea's as to what's up though…

Hi guys, I'm sure its been asked before but could someone send a picture of their targa straps and bags secured in the boot. I've just had the straps arrive and one is far shorter than the other so struggling to work out how the pair of targas are secured down. Any pictures would be greatly appreciated.

Hi, can anyone tell me which cars have wheel bearings with 38mm dia inner, 42mm inner dia, and 46mm inner ? Bought 2nd hand hub with 38mm on But bearing from amayama are all 42mm Z centre state 46mm Totally confused cos I thought all were same size. Look forward to any help.

My front side and head lights aren't working. The tail lights are working and the audio head unit dims when the switch is turned. The fuses are fine. Any ideas?

Hi - Got a suspected rocker cover oil leak, most likely exhaust side. Wondering if anyone has a detailed guide/procedure on how to do this please? I'm only a DIY mechanic and learning as I go, would feel way more confident doing this with some form of reference on what to do, including exactly what parts I need to order in advance.

The warning light has come on and on other sites I've seen posts saying it can be caused by low hydraulic fluid. How high should it be? They also said to use ATF but how can I tell if if that's what is already in? The power steering is unaffected.

Happy Friday all! I've finally started work on my Zed! It has sat in my garage since 2013 with only a couple of engine warm ups. The last time I turned her over was July 2023 when I discovered that my braided fuel lines had started to perish and were pissing fuel all over the engine bay. Fuel lines have now been replaced along with a new battery, oil, coolant and fuel. Pleased to report she's now starting up and idling fairly well. However, I went to move her out of the garage for the first time today and was unable to engage reverse gear. Clutch pedal feels ok but there's more travel than I remember before it hits resistance. I've found that I can get the car in gear wit…

Hi all! Hoping someone can provide me with a 123 etc list of steps I need to take to drain, flush and refill the coolant. Its a simple task in principle and something I've done on other cars before, I guess im just wanting to ensure I do it right first time. Not only that, I've seen competing advice across forums on whats best to do. Any comments/advise is always welcome!

Hey! - You're going to get sick of me soon. Just took the car out for a spin this morning, upon switching the engine off there is a fair amount of white smoke coming from the engine bay, smells like oil too. Cant see any visible leaks up front, I put cardboard underneath, came back in 5 minutes and there is a small-ish but sizable enough for me to come running here puddle of oil on the cardboard. Around the back of the engine. Which i assume is then burning off on the engine causing the smoke. My question is ultimately, what could it be? How do I fix? Understand ill need to get it in the air to be sure, but atleast a starting point from you guys would be much much…

Hi everyone Just failed the MOT for a weeping nearside front shock. Can anyone point me to a source for OEM spec replacements ? I'm thinking it makes sense to replace as a pair too. Many thanks Mark

Hey guys, I have a ‘90 na manual swapped 300zx and have finished replacing the wiring harness with a z1 manual harness to only come to a predicament. When I go to start the car, the fuel pump isn’t turning on and the car isn’t receiving spark, but it is cranking. I’m thinking it could be due to one of the plugs near the fuse box.. If anyone has any idea as to what I should do next that’d be great 😞

Hi guys, hoping someone has had this and can shed some extra light. i’ve traced a misfire back to 2x neighbouring cylinders both getting no spark. known working plugs and coil packs have been switched and swapped to test and it seems to be the coil pack loom. anyone experience this? it’s a UK 93’ TT Manual thanks :)

Hi Guys, I'm new here and sorry for no introductory post yet but have an issue with my Z and I'm told you guys are a fountain of knowledge. Ive a 93 Jap import 300zx TT manual. My issue is I started her for the first time in about 2 months (only driven for events or good weather). I was just leaving it warm up while fitting a new steering wheel when I notice the fuel dropping very quickly. I turned it off and got out and notice petrol in front of the right exhaust, upon inspection then once off I noticed it was leaking from the mid section of the right exhaust. Does this sound like an injector is stuck open? As im assuming otherwise the fuel would of stopped once I turne…

While rummaging around the fusebox area I noticed these two connectors not attached to anything. Anyone know what they're for?

Is there a fuse for just the sidelight?

So I’m trying to diagnose a misfire as she gets warm it gets worse plugged nisscan in and this is my data How do I upload a photo What’s the correct readings I should be getting anyone notice something that’s not quite right 🫶

Does anyone know the way to de-pin the stock audio female connector? I've tied all of my de-pinning tools that fit but nothing works.

Does the A pillar interior trim panel just pop off or is there anything I should be careful about?

I'm new to 300ZX ownership so apologies for the number of questions I'm asking. I'm acquiring components to upgrade the infotainment system, this includes an Android head unit with matching amplifier connected by SPDIF. I understand that if my car has the Bose system I'll need a bypass, but I don't want to buy one if I haven't got Bose. So my question is, how can I tell if it does or doesn't without taking off a door card or rear speaker enclosure?

Hello everyone, this is my first post in the forum as I mostly use Facebook, dare I say forums were a little before my time. 😛 Does anyone know where the ECU(s) pick up the speed sensor signal from? I am wanting to bypass the converter chip and wire it directly to ECU before it has been manipulated by the converter chip. As many people have stated in the past the speed sensor sends it's signal to the clock and then the clock relays it to the ECU but I'm struggling to figure it which wire it is. If anyone could help I would really appreciate it. Also I don't really fancy fitting UK clocks as many people have suggested.😉

My reverse lights (and reverse camera) started playing up intermittently and have now stopped working altogether. IT doesn't appear to be the fuse so I'm thinking it might be a dead reverse switch. A little puzzled if so as I had a manual conversion with a brand new '98 spec box and would assume (though not sure) that a new reverse switch would have been part of that conversion. In any case, if it is the reverse switch which has died - has anyone ever replaced one of these without dropping the gearbox? How difficult would it be to do? I've only managed to find one video online and it wasn't a particularly good / helpful one for a newbie to the job, like me.

1990 Nissan 300zx coupe Anybody have any experience removing the Heater Pipe assemblies without pulling the engine? The return pipe assembly bolts are visible from the top. I can't see the feed pipe bolts from the top or bottom. Also, the sec223 pipe assembly has been disconnected from all water hoses and bolted connections, but cant seem to snake it out, any suggestions?

The lever to release the fuel flap and open the boot has ceased to work properly.... I can no longer release the fuel flap, nor will the boot shut properly - any ideas? Could the cable have stretched or got stuck on something - and how easy do you reckon it is to fix. I do have a spare brand new cable if need be, but I have my MOT on Monday and the tester will need to access the fuel cap 😞 I guess I could pre-open the flap by pulling the cable lever behind the near side tail light - luckily I don't need petrol just yet LOL!!

Hi all, my prop shaft bearings are going (possibly) and I thought I’d look at changing to a single piece as I’ve heard it’s an upgrade as they are lighter. anyone know anything about them? Where I could get one? Are they an upgrade or am I wasting my limited squids?