New Z at our house

[nukeday]

This sounds like it could be a vacuum leak. I don't know enough about this series engine to question the valve train. On a lot of 4 bangers, this is where you'd check the valves. The old WD-40 trick in the intake area works on FI rigs too. Check every vacuum line you can find, replace them or cut them back a little, if they are in question. It's time consuming, but doesn't cost anything, and it's a great way to learn your way around the engine bay. It can provide tremendous payback if that's all the problem is.

 

If there is an air mass meter, you can usually check them with just an Ohm meter, and they are usually adjustable. I'm sure someone here can get you the spec's if it's not in your manual. If the air mass meter checks out, check the O2 sensor(s). Disconnect the O2 and see what happens as you ramp up from idle. (I'm assuming this is a closed loop setup.) I don't know if this year car has a TPS (Throttle Position Sensor), but if so, they are notorious for getting dirty and sticking, and I don't think it's marque specific. If there is a MAP/MAF type sensor, these can be very sensitive to vacuum leaks too.

 

I not even going to pretend to be a Z guy, but fuel injection does share some basic similarities during these years. I have some experience on both the mechanical (8V) and electrical (16V) fuel injection set ups on the Saab 900. The injector connectors with the horseshoe wire look a lot like those found on Saab's.

 

I'm really out of my league here, so I'll not post again regarding 'run-ability' issues, but maybe some of these things will pan out. Checking vacuum hoses, ohming stuff out and spraying a bit of WD-40 around the intake doesn't cost much. I'm really not much of a mechanic, so I always go for the easy and cheap stuff first. :D

 

Congrats to you both on this car, and good luck sorting out this running issue.

[Jester]

Thanks for the idea on trimming the vacume lines. Might be something for my helper to do. I did open up the MAS to make sure the flapper was moving OK. I checked the TPS as well. I have NOT done any OHMS tests yet. I was reading through the "fuel system" section of the service manual. That will come soon enough.

Next in line is adusting the valves, checking the timing and an oil change.

[Bleach]

The factory system is not super accurate as it is. I would leave chaning the AFM mixture to a last resort. Clean all electrical connections first. Main ones are:

Air Flow Meter, Throttle Position Sensor, Cylinder head temp sensor, ECU connections.

Also make sure all six injector plugs are making good contact. Clean your grounds on the intake manifold (little black wires that bolt to the center of the manifold where the main harness attaches) Maybe replace your battery cables and add a simple ground strap from the battery to the block and head.

 

The AFM themselves do go bad as well. Yours sounds like maybe it'll clear up with some driving. I've noticed my turbo Z is running with a bit more power after about 1000 miles of driving. It sat on and off for many years.

 

Here is the 1978 Factory Service Manual!

http://www.xenons30.com/files/FSM/1978%20280z%20FSM.zip

 

compliments of Xenons30. You can also go to xenons130 to get the 1979 FSM. The engine and electronics should be the exact same. Both FSM might have slightly different descriptions and pictures.

[Skib]

Hey Jester Ill be in town the beginning of the week, if you guys want a hand Id be more than happy to take cruise down. Ill bring some spare bits along and hopefully we can get her running like she should be.

[Bleach]

Z31 ecu swap! :thumbup:

[Jester]

I have a 1978 FSM. But thanks for the other as well. So far I have cleaned and greased the connectors for the injectors, start injector, AFM and the TPS. I forgot about the temp sender. That is one of the first things in the fuel injection section of the FSM. I'll do that and ALL the grounds, clean the battery cables and check/add an additional ground at the block.

 

Good ideas guys. I greatly appreciate the help. Please keep it coming.

 

Skib: Your welcome to stop for a break on your way home. Is Z-racer traveling with you? You still have my number?

[Skib]

Ya Iv still got your number, Ill be cruisin back up with my mom but I can come down with my Z when Im back.

[Jester]

Sounds good. Give me a call when your back.

 

Thanks again!

[Skib]

Will do :D

[cody]

maybe we all might be there at the same time... :P

 

i still gotta come over n get those parts..

[cody]

Any updates on the Z ??

[Jester]

Not a lot of progress on this one. We did mess with it a little the other day. Mainly just sitting down with the FSM and reading to each other. :D Sounds stupid but this new to me too. This is our first fuel injection venture. It's tuff enough to try and learn it, but, to try and learn it and explain it at the same time is tuff.

 

Pic of when we got it running the first time.

 

And after we realized that it still runs rich. I love it when she wears that shirt.

[Bleach]

That fuel injection always seems to run rich if one little sensor isn't right.

 

check and clean all major connections first... I wonder if I already posted that

[Jester]

Clean all electrical connections first. Main ones are:

Air Flow Meter, Throttle Position Sensor, Cylinder head temp sensor, ECU connections.

Also make sure all six injector plugs are making good contact. Clean your grounds on the intake manifold (little black wires that bolt to the center of the manifold where the main harness attaches) Maybe replace your battery cables and add a simple ground strap from the battery to the block and head.

 

 

That fuel injection always seems to run rich if one little sensor isn't right.

 

check and clean all major connections first... I wonder if I already posted that

 

:rolleyes::rolleyes::rolleyes:............Maybe. :D

[mklotz70]

I don't know anything about this FI setup....but a lot of FI cars have two temp sensors. One for the gauge and one for the computer. If the one for the computer is still telling it that it's cold, which seems to be the default setting on most when it doesn't get a signal from the sensor(open circuit as opposed to shorted).....it will run rich. I'd specifically check any temp sensors and wiring. But as I said....that's simply a guess based on all the other FI cars I've had and worked on....not based on a Datsun :)

[Jester]

Thanks Mike. I'm going to check ALL the sensors as soon as my helper is ready.

[Jester]

Not a whole lot of progress so far. We managed to figure that the temp sensor/switch is not doing it's job. SO....upon taking the thremostat housing off I found two zip ties wrapped around the bottom of the housing. :rolleyes: When I finally got the lower portion of the housing off, some JACKASS blew out the side of the thread boss and use F#%$&^@ zip ties to hold the broken piece and the bolt in what was left of the thread boss. :lol: Oh ya, it fell apart as soon as I got the ties cut off. So now were looking for a new lower portion of the thermostat housing. Does anyone have an extra they want to sell. I looked at the extras I have for trucks and they are differant.

We are also going to order all three temp senders/switches tomorrow.

 

We did manage to get the new master cylinder on and brakes bled. One step closer to driving it.

[Skib]

let me check my box-o-parts :D Im sure theres one somewhere

[Jester]

cool.

[Bleach]

oh yes, be careful with those threads. I've had to replace that housing before.

Also be sure whatever bolt you use to screw into the head isn't too long. It can stick through and touch the timing chain. There isn't much clearance inside.

[Jester]

Thanks Bleach. I did notice that one of the holes for attaching the upper peice to the bottom on this thing had the bottom blown out. Too long a bolt was my guess. I'm starting to worry about what I'm going to find in other areas as well. Time will tell.

[PharaohABQ]

Nice job finding a Black pearl. If that's the original paint then you've got a special car especially since those wheels look like the original Black Pearl rims. Those alone are worth more than you paid for the car. Look under the passenger side carpet and see if the factory papers are still there. Hopefully they are, they'll tell what the car was built with and it's order etc etc. I hope that you'll keep it the same BP paint color. It'd be a shame if you changed it. I know you'll have to repaint.

 

Sounds like you've got the engine almost running properly. That's cool, your Daughter is a lucky girl to not only have found the car, but also to have you as a father to help fix it up. All my z's I've had to do myself, since my dad was into other cars.

 

Unfortunately the Black Pearl Decals are almost impossible to find but that doesnt' mean they can't be found/reproduced... here's a Black Pearl link for more info:

 

BLACK PEARL LINK ON ZHOME note the rims.

 

Phar

[Cuts metal like mad]

Nothing helpful to add, I think these guys have it covered :D so just this :thumbsup:

[Jester]

Thanks for the link. I should email him and get this one registered. We are 100% sure of the fact it is a Pearl. It was repainted when a new core support and passenger fender were replaced. We found the factory 638 paint code sticker. It had fallen off the hood and landed in between some parts up against the drivers fender. My guess is they moved it when they repainted the core support.

Right now it is pretty rough. Not nearly as nice as we first thought. Oh well. The wheels are the factory "optional" wheels. The interior is pretty nice. Need carpet but that's it. EVERYTHING else is there and in great shape. We even found the original air tank for the spare. :D

Still working on getting it to run right. We replaced the temp switch with no luck. Not sure where to turn now.

[Skib]

:( sorry I still havent made it down man, unemployment monies arnt much for gas :blink:

 

 

do you have a cam that shoots video? I might be able to make some more educated suggestions if i could hear it run :D