MrChefur

I'll be sure to check it again, but I've done that (as well as every single ECU resistance/voltage/continuity test in the EFI bible) already.

You guys were right, the inside of the seals were worn out on a few. I replaced them all and got everything back together, as well as a hot valve adjustment. In this neverending saga, now I've got yet another problem. The car backfires out of the exhaust if I blip the throttle from idle, and my plugs are solid black which indicates the car is running rich. It also smokes out of the exhaust still. I cleaned the bullet connectors, but that didn't change anything. I'm gonna finish replacing the connectors for everything before I go on another witch hunt, but I'm pretty bummed out right now.

Guess who's back! After not being able to find a suitable valve spring compressor anywhere, I improvised and did it with a 13/16" box end wrench, which worked just fine despite being a massive pain. Problem is, the valve stem seals look brand new. They look exactly the same as my new Fel-pro ones. Here's a picture: https://i.imgur.com/Qe3dBLB.jpg Should I continue and do all the rest of the valves? Or is it possible something else is causing the oil to burn?

Yeah, as far as I can tell it's the same one. Problem is, the only ones I can find ship from the UK and I wanted to try my luck here before having to wait that long.

Looking for one to do my valve steam seals. I'm located in Murrieta, CA. Looking to buy, rent, or borrow. Thanks!

Ah, ok. I'll give them a good cleaning as well. Also, does anyone know where I could get a valve spring compressor near Murrieta, CA? Something like the KD 3087 would be fantastic so I don't have to pull the camshaft and such. If anyone here wants to sell/rent/loan theirs, I'd be very grateful.

It's an Aitex/Wells. I'll be sure to test it, thanks for the advice.

That's true, but a new one was only $8 and I figured it'd be nice to have.

I've got a new coolant temp sensor on the way from Rockauto right now since it was only $8. I'm not sure if it's a 240 vs 280 thing, but my coolant and thermo time switches are both injector connectors. They are color coded, however, and both work. I'll look into the fuel tweaker as well, thanks. Haha, I'm definitely getting ahead of myself here. My dads mechanic friend happened to pop by as well and thinks it's the stem seals as well. I'll do as you suggest and get those done before getting myself into a mess, haha. I honestly didn't even think to ask the Z mechanics if they had a sniffer. I kinda assumed it was a smog specialty shop thing. I've got new connectors on the way from Rockauto as well, but I'll be sure to clean everything thoroughly.

I'm gonna DIY it. I've got a spark plug compressor fitting from my compression testing kit around here and just picked up the seals today. I was reading that a bad PCV can suck oil from the crank case ventilator, so I changed that out and now I've got a new issue (yet again ) The smoke changed from a white to a dark grey/black. That means it's running super rich right? How do I even adjust that? By the way, I wanted to say thanks a ton to everyone that's helped me so far. I couldn't have done it without all you and the countless awesome posts on here.

I got off my butt and took it to the Z specialist today. Super nice guys over at McKinney Motorsport in Temecula. Anyways, they said it's almost certainly valve stem seals and that the smoke was definitely burning oil.

Didn't get to check it out today, work was longer than expected. I'm unsure if smoke is a new thing. I didn't rev the engine too high when it was sitting in my yard, and when I'm driving I can't see it much haha. Not a smoker, for what it's worth. I'll get back soon with what the exhaust is like. The smoke mostly occurs during deceleration, the videos were really only idling. I'll get another one tomorrow if I can't figure it out. How would I determine if it has a performance cam? When I took off the valve cover, the cam had the standard Nissan markings on it, although I suppose it could be reground? To be more specific, my dad says he misspoke and thinks it's a performance crank. Is it possible to determine if that's true without tearing down the engine? I don't particularly care as long as I can get the car running well.

The rebuilt engine only has 35 miles on it so far. I was trying to get it smogged as fast as possible since the cops around here are Nazis about driving without smog. Damned if you do, damned if you don't. How would coolant be getting into the exhaust? It doesn't have a head gasket leak. I'll pull the plugs again tomorrow but it's put out a consistent 150psi for the 3 compression tests I've done so far. I'll try the finger test too, thanks.

Yeah, I should have waited until after but I had to cancel the appointment. Got a new job and couldn't make it anymore. Smog station told me they didn't check the sniffer because it failed the visual due to the smoke. It was enough smoke to fill the whole shop. It only smokes under hard acceleration too. I will have to take a closer look at the actual color of the smoke later tomorrow, they told me that the color can indicate what is causing it. I've eliminated a cracked head or blown head gasket so far, but the white smoke leads me to believe it's running super rich. We'll see, I guess.

Welp, took it out to smog today and it failed the visual due to blowing white smoke out the tailpipe. This rebuilt motor has 30 miles on it so far, should I just run it more to break it in?

Yeah, I read the section and tried what it said. The adjustment nut wasn't doing anything, so I tore down the BCDD and put on another one from my spare parts bin, as well as cleaned the snot out of the throttle body. That fixed that problem. I'm still having the miss at idle but I've got an appointment tomorrow at a local Z specialist (McKinney Motorsports in temecula, anyone have experience with them?) so hopefully they know what's up.

Alright, now I've got a new problem. The throttle was sticking when driving, which I tracked down to the BCDD. I tried adjusting it but the adjustment screw didn't do anything, so I jumpered the sensor wire to 12v on the ignition coil which fixed the problem. My concern is that idle is at about 850 with the idle screw all the way in. Is this a problem? I recall reading that it should be set to 5 and 1/2 turns out from screwed fully down.

Thank you! Feels great to finally have it back to life. Here's the (crappy) video:

Found the problem! EGR valve had a rock stuck in between the plunger and the housing. Swapped in the new one and she just purrs. My dad thinks it has a perfomance cam in it too, but I have no idea since I lost the rebuild paperwork. Thank you everyone for your help. I'll upload a video of it finally running shortly.

EGR seems to be bad from what I can tell, it doesn't seems to be holding vacuum. I've got a spare that does, so I'll swap that on. Firing order is correct, I've redone it several times to make dead certain. Another idea: When I set timing, I put the crank with the mark lined up exactly at 0 and then inserted the distributor shaft in at the correct orientation (small side of shaft towards the front, pointing to 11:25AM). Now I'm reading something about needing to set it to 20 degrees BTDC? I also saw to read the sticker inside my hood, but it seems to have fallen off.

I've done the timing with a light already. The TPS certainly is designed to move like that, it's the range of adjustment. I just finished adjusting it properly following that link. Firing order is also correct. I think I'm finally onto something with the following: I have a spare fuel rail, complete with injectors. I swapped injectors on the half of the rail where the "clean" plug was, then used my stethoscope to listen to each injector. Cylinders 4-6 (the new injectors) were far louder than 1-3. In fact, number 6 made number 1 sound like it wasn't firing at all. I'm going to rig up an injector cleaner and come back with the results.

Alright, finally checked fuel pressure. 37psi before starting (starter solenoid disconnected) and sat about 32 while idling. Bear in mind it currently idles at about 1k rpms. I disabled the cold start valve by plugging the line, to no effect.

Alright, here's a video of the issue: Video ends because I'm an idiot and shocked myself with the wire . Also, I know the connectors are old. I've got new ones on the way. EDIT: because I didn't explicitly state it, the engine continued running exactly the same after I pulled the wire and shocked myself.

Throttle position sensor has two screws on either side and looks like it was made to be adjusted, even has little hash marks. Not sure what for. Battery is pretty old, haha. It's charging well when running though. I unplugged injectors one by one while it was running and all of them caused the engine to stumble until it stalled. I also messed with the AFM and rotating it caused the following results: All the way shut against the stop: engine stalls (no suprise) Let it sit where it wants to: runs like in the video 10 degrees further: idle RPM goes up from 950 to about 1200 No real change until about 20 degrees past that, where the engine begins to stumble 15 degrees past that: stalls I pulled the wire from the "clean" plug and started the engine, it ran the same as with the cable plugged in. I did as you said with the spark, and it appears to be getting good spark which thoroughly confuses me. I also swapped the spark plug wire with another and it didn't change either. Does this mean it's the injector? I also checked compression, here's how it read (in correct order, from front to back this time ) 148 145 147 150 145 145 I'll go pick up a fuel pressure gauge and report back.

I just pulled the spark plugs again on a whim, and something weird is happening. With the spark plug closest to the front of the car being number 1 and the one closest to the firewall being number 6, here's what I found: Black with soot. Most of it rubs off by hand but some is stuck. Same as 1 Same as 1 Somewhere in between clean and sooty Basically clean? smells like gas. Had minor black soot but nowhere near as much as 1 Same as 1 I also listened to the injectors with a steel tube and all of them are clicking at the same rate. I'll try the other troubleshooting and come back, I just wanted to type this while it was fresh in my mind.