left the battery unhooked all night now the car won't start

[memmert]

OK so I have this electrical problem. Well that's not what i'm writing about exactly it's the turn signal/dimmer switch going crazy but I found someone to fix that on eBay I think.

I have an 83 280zx NON turbo 5 speed.

The problem is that I disconnected the battery last night because I didn't want the lights to come on in the middle of the night and drain the battery like it did at work the other day so....

 

I get in to start it and it cranks over but won't start. This car has NEVER even hesitated to kick over on the first crank and now not even a tremor of firing.

What's up with fuel injection? with a carb (i'm an old camaro guy) i'd just pour some fuel in the carb and it'd kick right over. Now what do I do?

Maybe i'm over complicating things and maybe it will start right off when I get home tonight but does anyone have some advice on the first few things I should look for/try?

 

Many thanks. I have searched a little but but not sure how to phrase the question. Assuming nothing drastic has changed or components have broken overnight the logical conclusion is that the fuel pump just isn't getting fuel all the way to the injectors and i'm not sure how to prime it.

Am I completely out of my mind?

[Ledphoot]

You can give it a shot..a small shot! of starting spray in the airbox and if its firing it will hit and sputter at least. Sounds like you may have damaged a wire when you pulled the cables loose or you may have a problem in the electrical side of the ign switch itself. Did you accidentally arc anything removing the cables? This can blow a fuse or trip a relay as well.

[memmert]

It's so hard to tell with electrical components if anything got buggered or not until you trace it out. I didn't see anything out of the ordinary when I pulled the the cables off the posts (and just left it).

I will pick up some starter fluid on the way home tonight.

 

Thanks.

[memmert]

Or so I think anyway. If I squirt starting fluid into the airbox it kicks over but won't stay started.

I can't hear the fuel pump but I could never really hear it before either so I'll next check the Chilton's manual and this evening see if I can find the fuses or relay's? to the fuel pump and see if I get anywhere.

[Paz8]

There are 2 fuse links that feed the EFI computer, the computer turns on the fuel pump, pump relay is on pass. side above kick panel. The links are in a small plastic box near the battery. Before you go into checking for an electrical problem, jack up the car and take off the rear pass. side wheel so you can see the fuel pump, have someone crank the engine while you feel the pump to see if it's running. If it feels like it's running then check the fuel filter or you gas tank gauge to make sure you have gas in the tank.

[memmert]

OK so... I checked the relay by the battery by putting my finger on it and having a friend turn the key on and off and I could hear/feel the click of the relay so I believe it to be OK. I looked at all the fuses in the passenger side kick panel (in the car) and nothing is blown. I also checked the fusible link and found that it is breaking up so I put a solid piece of copper in it's place but still no joy. (I check this fusable link by testing the resistance on it and it would bounce all over from zero to lots of resistance where all of the other fusible links all read zero).

 

Is there another relay hidden somewhere? The parts house lists two different relay part numbers and they both have different pin configurations so is this different models of relay for different cars or does this mean there are two relays? It doesn't make sense to me that there would be multiple relays in the Fuel circuit but then again I don't know the first thing about electricty really and definately not much about fuel injection.

 

Can I put power directly to the fuel pump and see if it triggers? it seems that I should be able to...

[memmert]

OK, so I finally took the tried and true advice of a bunch of posts on the board and took apart every connection I could find. I can get the car to start now but it does after about two seconds every single time which tells me it's either loosing a signal somewhere or it's getting the incorrect one.

Anyone with an opinion please chime in but I think it would be one of two things.

1. I broke off a bolt trying to get the exhaust pipe unbolted from the exhuast manifold and only got another a couple turns loose. I ended up just leaving it there and getting the new clutch in anyway. I wonder if the O2 sensor is now getting the wrong signal and passing it back to the computer because of the leak?

2. The computer is defective after all these years maybe? The problems started when leaving the battery disconnected overnight so I maybe blew something when re-connecting the battery.

 

Odds are the simple and obvious possibility is the likely one. I need to get the exhaust leak fixed anyway so that will rule out #1 soon.

I just can't decide whether I should buy a header since I am going to have tear into that spot anyway or just leave it stock for now?

[b__sosick]

I think we have the same electrical problem. My blinker will randomly turn on. just on one side, not the hazards.

I'm hoping this will go away when I swap over to the 300zx ECU

[Okimoto]

Have you tried leaving a fuel pressure gauge on the car?

 

[edit] just re-read the post. Have you tried turning the key to "on" for 2 seconds before cranking to see if the fuel pump will build up pressure?

 

You can also disconnect the fuel pressure regulator and test like that also.

 

Correct me if im wrong but the o2 sensor shouldn't keep the car from starting though, since the computer "should" ignore the input until the car warms up the sensor enough to use it?

[memmert]

I am going to mount a fuel pressure guage under the hood this week but I still think it's getting fuel. I did turn the key on and leave it and now can hear the pump prime then quit I also put a voltage doohickie (the pen with a light in it) on the fuel pump circuit in the back and watched it while the car was started and it stayed on so I know i'm getting current back there.

 

The car does actually start but won't stay started unless I really pump and feather the throttle even then it smells really gas heavy (I forget the right term lean or rich).

I did just read last night that the O2 sensor does not kick in until the car is warm so maybe your right that there is something else going on. I will keep tracing connections.

 

b__sosick - Yeah, i've had wierd light issues lately too. my high beam/turn signal switch is all fubar and needs rebuilt. I am guessing though that things will settle down somewhat after the labor i've put in lately. I'd recommend you do the same thing I did. I took off every connector I could find and sandpapered the blade and opposing connector where I could then put dialectric grease in the connection before putting it back together. This is time intensive but I know the car a whole lot better now and have also spent hours looking at wiring and comparing it to the schematics. Time well spent as far as I'm concerned with these old frustrating cars.

[Okimoto]

Is this the car where the battery is closely located to the mass air flow sensor? I remember it was in my buddy's 84 maxima.

 

Just throwing an idea out, but maybe an inadvertant knocking of the sensor with a wrench may have caused that little flapper to jam up?

[memmert]

The battery is actually back by the firewall and the AFM is up front by the nose.

I think one of two things are happening either I just haven't discovered the right connector yet (and re finished it) or an electrical component somewhere in the system finally just gave up the ghost.

 

I have a test ECU coming (not to leave in just to swap out and diagnose with) and I found a couple more connections that may be a factor (block temp sensor, etc.).

 

In doing this and considering the frustration involved i've considered doing a few HTML pages of the wiring schematics with clickable links so when you see a "EFI Relay" with certain colored wires going to it the link would take you to an actual picture of where the $()%^#(* is so people don't have to rack their brain for so long.

Well see if I ever get around to making it. It would only take maybe 5 hours or so.

[memmert]

Holy moly, what an ordeal...

So the car runs albeit I still have some work to do.

Here's what I think happened. And it's all due to the @#%(*$ weather.

So first what happened is that the lights started going all screwy (still not totally fixed I think but I at least have an idea where to look now). Then I disconnected the battery overnight and the thing wouldn't start again because the Fuel pump wouldn't get any or enough electricity.

 

I think because the car is so old and I live in the Northwest water leaked into the cabin and corroded the connections on or by the ECU. I cleaned every connector I could find from the fuel pump forward to the Air Flow Meter. The car would then start but wouldn't stay started for more than two seconds (that two seconds was dead on exact everytime) that kind of told me a signal was not getting to the ECU or a false signal was getting there but I couldn't find it. I just kept removing connectors and sanding them down and adding dialectric grease, reconnecting them and then trying to start it again. Same result... %)#$Y)(* frustrating is an understatement.

I had just about convinced myself the module screwed onto the side of the distributor may be flaking out (you can tell I was grasping at straws by this time) when I was really working to get the second lower connector off of it (which I never did and I still can't get the friggin thing off) but that's beside the point.

While I was all hunkered down over the distributer my nose was just a few inches from the rubber boot on the AFM that connects it to the intake manifold, well as it turns out there was a small gap letting air into the intake that the AFM wouldn't be able to read. I wrestled to get it back on but since it's about 30 degrees out the rubber boot isn't very pliable so I just kept working and taking crap off until I finally ended up with the AFM in my hand so I thought Hmmm I wonder if it will stay started with the AFM totally out of the picture. It did... It was rough but it stayed running so I knew I was about to get it fixed.

I have the boot on securely and everything reconnected and it runs as good as it ever did now.

While it was down I put a new clutch in it as well. I still have a ways to go, I still don't know what is draining the battery? As it stands the car is completely dark so unless a light is coming on intermittently in the night it's a draw somewhere else.

Regardless I am happy that that nightmare is over for the time being.

 

Thanks to everyone on the board who has ever posted information about these 280z cars it made this 100 times easier to troubleshoot, and especially thanks to all who replied to my thread I appreciate you all taking the time.

 

Peace out,

memmert