1990 300zx (na) 2+2 no spark

[nismo300zx1990]

Hello i am having a spark issue.

I have just replaced the motor in it.
1. I have power to all my lights in dash and out side of car
2 new injectors and plugs, getting gas, pulled three coil pack and grounded to see if spark all three that i checked had nothing.
3 car has been sitting for awhile.

I am thinking i maybe a relay do to it sitting so long. But not to sure. Is there any things i should be checking other then ing. Relay and eccs relay?

Thank u if u need anymore info just let me know i will try to explain more.

[t.mcginley.jr]

Did you test the voltage on the battery? Should be around 12.4V. Does it crank at all?

Could also be corrosion on the various connectors in the engine bay. Pull some of them off and look for any green corrosion.

[t.mcginley.jr]

Did you test the voltage on the battery? Should be around 12.4V. Does it crank at all?

Could also be corrosion on the various connectors in the engine bay. Pull some of them off and look for any green corrosion.

[nismo300zx1990]

Ok some new info. Yes it does have good powerat the bat. I also have power to my injectors. When i have someone crank the car over i can hear my injectors ckicking. Also all my dash lights come on, check engine light comes on and everything. I have been doing so research on this now and i have taken my PTU down to my local nissan dealer to have it tested to find out my PTU is bad. He checked it with a ohms meter that i do not own. Anyway i do think that is my problem so i will order a new one f z1motorsports.com. also would anyone recommend getting a used one and will a tt model work on a na? Thank you guys for all the knowledge i wouldn't know what to do without is fourm.

[itsa300zx]

Just by a used version 2 style with th eadapter harness, They go for about $30-50 shipped with the harness. Check classifieds here and TT . net. NA and TT are the same.
Here:http://www.twinturbo.net/nissan/300zx/f ... rness.html

[nismo300zx1990]

Ok I have got my PTU in the mail today and installed it into my Z. However when i tried to start my Z she still did not fire..... I strange part is when I went out to check the Ptu it was hot is this normal? I am worried it maybe my C.A.S. I just looked up how to check my ECU for codes. I ran out of time tonight to check them but i will tomarrow and post what is up... Any insight on this I would be so greatfull. Im am just ready to here her purrr after putting all this work in her. thanks again guy i know im in the right place.

[mrmoose]

double check to make sure all grounds are connected! crank her and then pull the plugs, if they are wet its not the cas, and you should be getting spark since the cas tells the injectors and plugs to fire.

[nismo300zx1990]

Ok i just got back from checking a few things.

1. I checked the codes on my ecu. the code that is coming up is 21. Ignition signal circuit i think.
2. I pulled my cas out and looked at the connection it wasnt the best but didnt look bad either.
3. turned on my car to acc. had a spark plug and coil pack from my car out and grounded. rotated my cas and herd all my injectors clicking and spraying still no spark.
4. cleaned my cas connector with some 2000 grit sand paper and a flathead screw driver (couldnt hurt right?) still no spark
Just thought i would share my problems hope we all can come to a conclusion.... Thank you everyone for your time.

nismo300zx1990

Oh also can anyone link a pic or a idea where all of my grounds are. I only know on the one on the back of the plenum and the one on the big on the block to bat and firewall.

[mrmoose]

i know for sure there is a ground up in the fron of the drivers side right up near the corner of the radiator, thats the one i forgot. then there is a few smaller ones that go to the plenum not just one.

[nismo300zx1990]

Is there any diagrams where these grounds are im not to sure if i have all the grounds one then.

[mrmoose]

http://www.300zx.co.uk/cgi-bin/manual.cgi

[nismo300zx1990]

ok here is some new info. I looked at my whole harness today and notice one ground on the back of the plenum was not connected. tightend down that bold and bam have spark. now my new problem is i noticed my timing was a little off. tomarrow i will be doing the timing on my car and was wonding if anyone had some tip they would like to share.

[t.mcginley.jr]

Timing adjustment procedure + tips:

http://www.twinturbo.net/net/viewmsg.as ... _id=922678

[nissanfreak12]

ok here is some new info. I looked at my whole harness today and notice one ground on the back of the plenum was not connected. tightend down that bold and bam have spark. now my new problem is i noticed my timing was a little off. tomarrow i will be doing the timing on my car and was wonding if anyone had some tip they would like to share.

How do you know your timing is off? Have you recently done a timing belt change?

.

[nismo300zx1990]

ok some more info.... I do not think my timing is off now. I took my radiator out and look at all my marks to day and everything matches up well except one cam gear that have the cas on it. I look like it is a half or my be one tooth off. I dont know if that is a issue or not. second this is after all of the checking and tring to start the car when it had no spark i beleave i flooded it. so i think that is the reason it did not start after i fix the no spark issue. I will let you know later tonight if she starts after i have let all the pluges and cylinders dry out there were really wet. oops. wish me luck guys. if i works i will do a summer salt i promise....

[mrmoose]

ok here is some new info. I looked at my whole harness today and notice one ground on the back of the plenum was not connected. tightend down that bold and bam have spark. now my new problem is i noticed my timing was a little off. tomarrow i will be doing the timing on my car and was wonding if anyone had some tip they would like to share.

told ya!

how did you notice it was off? the marks are off?

[nismo300zx1990]

Ok more. Still no go on the start. Is it possable that my spark is not strong enough? I have spark but to me it seems week. I stuck a volt meter to it the coil pack and was only getting 1va is that normal. I have gas compression and a fait spark. Anyone on here have this problem. Also i took yhe grounds off and cleaned the connections too but still nothing.

[nismo300zx1990]

im getting so confused. ok it seems to be like this. I check all my grounds, my connection to my PTU all fine. I go to do a ecu code check it comes back a code 55... I then go and try to start the car and nothing. recode my ecu it then tells my code 21??? go back to engine bay go over all my grounds again and ptu connectors the code the ecu again. code 55. go to start the car and nothing again. code the ecu and code 21 comes up again. I just bought a PTU could i have got a bad one out of the box?? anythoughts would be great. I have almost scrached a damn hole in my head over this. Oh also when i did check for spark with the coil pack and spark plug out and grounded i would get a faint spark. almost not even visable. is this normal? I can go to my lawn mower and the spark on that would make you piss yourself lol. anyway im not going to give up on her....

[t.mcginley.jr]

Where did you get your replacement PTU from? If it's used it could be shot as well

Supposedly the PTU's from a 96+ J30 don't fry as fast because they are the 2nd gen ones

[nismo300zx1990]

I bought a new one from Z1motorsport. However when i put the new ptu in and tried to start the car the ptu got really hot so i unhooked it. Then i found a ground not connected. I connected the loose ground. Then checked for spark and had spark. However now i cant get spark to come back. When I code the ecu it comes up with code# 21. I go check all grounds and disconnect the ptu and reconnect the ptu. I go back and code the ecu again i get code# 55. I then try to start the car i get nothing. I then recode the ecu and i get code 21 .... and even when i did see spark it was not very strong. I am starting to think its a wire or a bad ground. I checked all the three grounds with a volt meter and got all the same readings on all grounds. And i mean the wire and not thon. I dont think i forgot anything. How do u guys feel about some white grease for the ptu? Idk im tired. Let me know if i should check something.

[demonZ73]

im not sure if you ever unplugged your ecu but make sure its plugged in and the screw is in nice and tight i made the mistake of not tightening it all the way and my car would not start because of no spark beacause it was not tight..........just trying to help

[nismo300zx1990]

I thank everyone for their imput and ideas. I have never unpluged my ecu. However the car has been sitting for a long time. I just finished rebuilding the motor. Everything is new besides wire harness. I am checking everthing now with my volt meter. I checked the ptu ground by unpluging it and using a ohm setting and touched one probe to the black wire and the other probe to the plenum and it reads 0.5 next im going to check my coil pack wire with the ignition on and check the middle wire for volts. Anything eles i should check?

[Christophers300zx]

So I let my 1990 300zx run out of gas and sit for about 6 months I put gas in it new plugs ptu and we'll I can smell fuel but it isn't getting any spark any ideas what could be wrong with it any help would be appreciated thanks

[nismo300zx1990]

I found out what my problem was. I found out that there are grownds on the plenum that need to be tight or you will fry your ptu. I learned this the hard way.

[Christophers300zx]

That's good man I wish I could find out what's wrong with mine I love this car but I tell u there a lot of work I can't figure out why it's not firing maybe the cas but I still hear the fuel pump comin on and stuff so idk ecu or cas is the only things I can think of

[t.mcginley.jr]

Have you checked for codes yet?

http://www.nicoclub.com/archives/nissan ... ostic.html

Usually a bad CAS with throw a code 11. Are you running old style (square connector) or new style (oval connector) injectors?

[Christophers300zx]

We'll it has the old style square injectors but it has one brand new one but I mean I can smell fuel and hear the fuel pump and stuff but I got another cas today I'm gonna try and I don't have a way to test for codes

[nissanfreak12]

All you need to check for codes is a charged battery with some power, a key to turn on the car, and a few tools(10mm and flat head screwdriver). Actually really simple.

[Christophers300zx]

How do u check codes like that? I got all that stuff

[nissanfreak12]

Click on the link, JR posted this earlier.......

http://www.nicoclub.com/archives/nissan ... ostic.html