350z_z33.

So I was working on the Z yesterday, and unplugged the MAF sensor (forgot to unplug the neg terminal for the battery). I had my friend start the car, and it wouldn't start. It would keep on cranking but wont catch. I plugged in the MAF, and unplugged and plugged back the neg terminal. Car still wont start. When turning the car to the on position, the fuel doesn't prime. The check engine light doesn't blink anymore like it used to. I think some other lights are missing too. The fans also turn on, as soon as I turn the car to the on position. I think the ECU isn't connecting to the car, because I tried to do the ecu reset, and that didn't work (no check engine light) so I left the neg terminal unplugged for 18 hrs and that didn't do anything. Tried jumping the car, wouldn't help. What should I check from here. I did a lot of research and no one ever posts the solution to the problem. I am going to the junkyard tomorrow to get some parts, and fusible links, maybe that would get the car running. Someone please help, any help would be GREATLY APPRECIATED!!

350zchad

iTrader: (1)

strange..what were you working on?

350z_z33.

I thought my MAF sensor was put the wrong way, due to having not very good throttle response, checked it, and it wasn't. So I decided maybe if I started the car, I could see if the MAF affected the car in some way, which I couldn't tell if it was or wasn't because after trying that, the car wouldn't start.

350zchad

iTrader: (1)

quite possibly damaged it as that would keep car from starting

350z_z33.

True, but do you really thing that it would stop the ecu from connecting? And also the fuel pump from priming?

pr_350z

sadly im in the same situation as you, my car wont start. Do you have any friends with a nice mechanic-type computer? not a simple ebay OBD2 reader. that would give you a better idea of the ECM being good or bad(if that computer connects to the ECM, then its ok and functioning... if not well it probably need either replacement or fixing). my car wont give any signal through the OBD2 port, giving the idea it needs replacement... which im working on.

pr_350z

by the way check your ignition coils, especially the ones closer to the back(i think the cylinder numer 5 and 6 ), do they appear burnt? like a little bump on the opposite site of the connector?

350z_z33.

Good thing we met on here with the same problem! I checked one of my coils it appears good! I don't think it really has to do something thru the engine. And I really don't recommend replacing the computer unless you know for a fact is the computer. I have a friend with an expensive OBD ll reader (is that what you were referring to as mechanic type computer?), I'll try to borrow his to make sure, but I think I already know that my ecu isn't connecting, because my CEL isn't blinking as it should when you have the car on. I think you should check your fuses and switch out your ECU relay with your headlight relay and see if it starts. I don't think the ecu is bad for either of our cars(due to it being a very similar problem). I don't think its the ecu because I replaced my ecu with an ecu from an 04 and CEL still wouldn't show up on the dashboard. I know that the CEL is supposed to come on because I own this 04 ecu (had it lying around), and I remember that when I used to connect the ecu, I would get a CEL blinking (even when the car is just on and not started). BTW I originally can't start my car with this ecu, because it hasn't been programmed with my car/keys/other parts. Do you have anything else I should check for? And do you think that it might be a fusible link?

350z_z33.

Also just wondering, how did your problem start?

pr_350z

yes for mechanic type computer i refer to something like a snap-on. I already switched my relays and checked every fuse, and sadly it would not work. Mine seem to short something out and burnt those 2 coils and made the ECM unresponsive (BTW previous owner of my car seems to have deleted the CEL, thats why i always use the OBD2 reader). But for the test you made with your extra ECM, I think you might have a loose ground(that would prevent the circuit from being "complete" and thus your ECM not giving signals of life), checked those?

pr_350z

oh my car burnt an ignition coil... replaced that. weeks later burnt another ignition coil(all while driving) on the second time the car stopped starting... it just cranks.

350z_z33.

Earlier I checked my fuses and they all turned out good. But my problem was that I only checked one side of the fuses, and the ones that normally are on, all worked (due to only checking one side). Also when checking them, I went thru them quickly, so I thought that maybe I skipped one. So I went thru them again, and it turns out that one side of one of my fuses lit up the circuit tester, but the other side didn't. So I replaced it, and now my car starts. I would reaally recommend checking the IGN & ECCS CONT fuse (in the fuse box, next to the battery). Maybe when your ignition coil burnt out, and this fuse also blew. I know you went over them, but would really recommend going over that one again (pull it out and take a look). If the fuse isn't blown, then maybe take your ecu to a shop, and get it checked out, and if its bad, either get a new one, or get it repaired. And before you do that, go ahead and smell it, and see if it has a bad burnt smell to it. I also would recommend getting all you coils replaced after you get this problem solved, so they stop burning out, and causing other problems. Let me know if that works out. I also have a question to ask you, maybe you could help me with this problem I have had, which I was working on, which caused the fuse to blow (causing my car to not start). I've already posted this problem up on this site, but no one really seems to want to reply. I have bad throttle response. Like I have to hold the throttle for about 1 second for each 1k rpm it goes up. You think you might have an idea what might be the problem? Maybe the MAF sensor? Because the last time I messed with it (when the car wouldn't start afterwards {this problem}) the throttle response got worse (after I got the car started just now). Or could it be something else? And I really hope you get your problem solved.

travlee

iTrader: (8)

did you change the tail lights out to the LED's?

pr_350z

That's great news, at least your car works now. Well as far as throttle response I have very little to no idea on why might cause that, but as usual inspection for that I would look at spark plugs, the MAF sensor(which you already did), and the throttle itself. If I'm not mistaken I have heard of this throttle to give problems after cleaning them, and that one of the solutions for some of its problems its the relearn procedure from nissan itself. other than that I'm out of ideas. BTW was the fuse that gave you problems the IGN & ECCS CONT fuse?

jhc

private party, peerz.

pr_350z

well at least i did not change mine to LED, dont know if that question was for me sorry.

jhc

It's a legit q, actually.
When I get in a spot like this, I retrace my steps and say,
"What has changed, what did I touch?" gl

travlee

iTrader: (8)

it is a known issue that the de's that put in the led tails, have throttle response lag

pr_350z

...

pr_350z

i have a feeling all these problems are going to burn thru my wallet.