welp she runs, but having idle problems

[j-z]

thanks alot dontbugme, you know what i looked at that fuse and noticed a lil burn mark on the side of the copper. i pulled it out to look at it closer and it was still connected, just had a burn mark on one side of it. that was the first fuse i pulled out when looking at all possible causes. what is this fuse for btw? could having the charger on there for so long pop it? ill def try jumping that fuse tomorrow morning cause its lightning like a biotch right now . get back to me on what that fuse is for as im curious. thanks a bunch man. florida, it doesnt even click at all. i know its not my afc wiring as that hasnt been touched ever since i installed it a year ago. my car is water tight too. somethings causing the ignition to not get power. if i find out what that fl 75a fuse is tha tjust may be the culprit. i bet that fuker is like $10 at nissan too.

[dontbugme]

That is the main power fuse. I saw one break, not melt on a '91 auto 240sx (I think- it was my nephew's car) after a slight accident but pieces would connect intermittantly. Looked fine from the top but when I removed it and took the plastic top off I could see it was the problem. I jumped it and the idiot lights, brake lights signal lights and more importantly the starter all started working. I spent about an hour checking the brake switch and park/neutral gear lever switch before I latched on to that fusible link. Hopefully, this is your problem. As others have mentioned, make sure the pos and neg terminals are clean and tight and the ground straps (two) on the engine are tight with no corrosion.

[j-z]

alright well i just went out and took a look at everything again. i tried jumping that fl75amp fuse and that was not the problem. i rechecked all other fuses as well and found nothing. its def not the ignition switch as i took that apart and it looks perfect. i get turn signals with the switch on (they blinked on the cluster). all of the idiot lights illuminate when i turn the key like normal. my afc still does not come on which is wired directly into the ecu and thats where it gets its power from. still no starter at all, and i dont think i heard my fuel pump come on either. wtf could it be? is there a relay that sends power to the ecu once you turn the ignition on? where does the starter get its signal from? im thinking maybe a relay went bad somewhere, and im thumbing through my fsm with no luck at all. i guess im gonna go borrow that auto ecu just to eliminate one more thing. grrrrrrrrrrrr...... yall have no idea

[j-z]

ok i found my ignition relays and an ecu relay. i swapped them for ones i knew were good and nothing. i also noticed when id hit the ignition on when all of the idiot lights would come on as normal, my check engine light didnt come on. i didnt get to borrow the ecu today, but tomorrow i will. does it sound like that could be my problem? where does the starter get its signal from? i know it has a two prong connector on it.

[dontbugme]

Here's what the FSM has for the starter wiring diagram. In between the battery and the 30A fuse is that 75A fusible link I'd mentioned and you already jumped. Since you're getting power to the ignition switch that 30A fuse appears o.k. To get voltage to the starter solenoid it has to pass through terminal 1 and 4 on the switch and assuming the clutch interlock switch is working (jump terminal 1 to ground if not sure) the current passes through terminals 3 and 5 on the clutch interlock relay directly to the solenoid on the starter. When that pulls in, the starter being directly connected to the battery, should turn over. According to this diagram the ecu has no effect on starter operation.

What happens when you turn your key to the start position, does the solenoid click, do any of your dash indicator lights go dim? It sounds like a bad connection problem. How'd you wire the battery from the trunk or wherever you moved it to the main power panel and starter?

[j-z]

no none of the lights go dim at all. the starter does nothing at all, not even a click. its not just a starter problem im having. my afc which is wire to the ecu no longer comes on when in the ignition position. my check engine light doesnt come on when all other lights do on the cluster. i dont hear my fuel pump come on either. the car hasnt moved in like two months now. havent changed any wiring at all except for when i tried to wire up a bad z32 maf, but its now back to the stock one and it runs with that one on it. my battery has been in the trunk with the same tool less quick release terminals for two years now. what really gets me is how the check engine light doesnt come on when all the others do, nor does the afc come on which is wired directly to the ecu. what all could cause the ecu to not get power? same with the starter and fuel pump? this is gonna be a bltch!

[dontbugme]

I know you said you checked your ignition switch but I'd double check and make sure that you have 12V to ground on terminal 1 and with the key in the ON position you have 12V to ground on terminal 3 & 4.

[j-z]

ok after looking at my fsm in in the electrical system i think ive pinpointed the problem. on page EL-14 you can see #3 coming off the switch is B/R. now that wire goes into the first ignition relay, but before it goes into the relay, on the same wire, it Ts off to main, ign/sg, injector, fuel. the part im looking at is where it Ts off into those four areas. now i know the relay is working fine because i have turn signals, and the chime. but the areas im refering to are before that relay anyways. on the diagram it just shows the wire going off and straight to those areas. this is where im confused... it doesnt say where else to look to follow that path, or does it just end in those areas? help a brotha out dontbugme. pleeeeeease

[j-z]

HAAAAAA thats the exact page ive been looking at and refering to other pages for the past hour. i wrote that whole last post before you even posted that up. yeah i dont think its the ecu after seeing this layout. do you see what im refering to? how do i trace those down? test the switch? ill def do that first thing tomorrow morning with the multimeter. if you could give me some help/insight on what im refering to on how that wire branches off of #3 thatd be sweet. does it just send power straight to those or what? also note that i do have blinkers and the chime so i know im getting power to that ignition relay. the main on the wire that branches off, could that go to the starter? i really appreciate your time.

[dontbugme]

If your fuel pump isn't working and neither is your MIL (check engine light) you don't have power on terminal 3 of the ignition switch or ther is a break in the line between the switch and where it connects to the Ignition relay-1 at 'K'. No voltage to that connection would cause no fuel pump or MIL light. Check to see if you have voltage to the 7.5A fuse (2), or any of those fuses on terminal 5 of the ignition relay and ground with the switch in the on position. This will be easier than pulling the ignition switch. Do any of those circuits work? Also check and see if you have voltage to the 15A (24) fuse for the fuel pump and ground with the switch in the on position.

The 'T' off terminal 3 of the ignition switch appears to go directly to the ECU to control MAIN, IGN/SG INJECT, FUEL according to the ECU connection diagram.

None of this still explains the starter malfunction unless it is the switch.


Modified by dontbugme at 8:26 AM 6/29/2006

[dontbugme]

Here's the schematic I mentioned in my previous post:

[j-z]

im about to go out and check everything with the multimeter. the switch is already exposed, but ill check evertyhing you mentioned. ive been looking at all of those pages youre posting in my fsm. so you think it could be the switch itself? i took it apart and everything on the inside looked fine. where i think my problem is where that line Ts off. its from the T to those 4 areas. so theres no fuses before those areas or anything hmmmm. i wonder how i could trace down that wire while its covered up in looms. check back in an hour or so and ill post up my testing results.

[dontbugme]

Further inspection leads me to believe the devices listed on the 'T' off the ignition swich are controlled by the ECU. See the ECU circuit diagram on page EC-7 in the FSM.

[j-z]

ok i tested everything you suggested and every single thing checks in good. hmmm... so you think trying a different ecu would be a good idea? that really is my only resort now. well, before i give up and have a professional trace down whats fuked. let me know what you think. i still have no check engine light coming on, nor my afc. i forgot to check if the red LED light on the ecu will blink before i put it back in.

[j-z]

alright, i see that the MIL is coming directly off the ecu (one of my problems). the fuel pump is as well (another problem). what about the neutral position switch for the manual (which is what i have). could that be why the starter isnt doing anything?

[dontbugme]

If you're getting voltages at all those places then I'm at a loss. Guess the next step would be to try a known, good, ECU. Then there's the starter....It could be the clutch inhibitor switch but this could be easily checked or jumped. It just bothers me that all this just happened. Originally, the car started, died and then wouldn't turn over. The only thing electrical you touched was when you took out the battery to have it tested and then reinstalled it to find it did the same as before. Of course, even with a bad connection you could still have voltage - it just wouldn't flow enough current to operate anything. Have you tried your headlights and are they nice and bright or dim? Is your car equipped with the anti-theft system? Sorry, but I can't think of anything else. When you get it figured out, please let us know what happened.

[j-z]

yeah man im totally confused on how this happened as well. i guess thats why i totally hate doing anything electrical (diagnosing wise). no i dont have the anti-theft system in my car. and also, this all happened before i even removed my battery. i know you know that, but just confirming about having a bad connection. what about the neutral position switch? could that somehow keep a signal/power to the starter? im gonnna get that auto ecu tomorrow,, so ill def post up with some results. and hey, another member from here, chrislis, hes local to me and pretty much the exact same thing happened to him. was doing a turbo install with multiple people working on his car at once. he went to go crank it and nothing. he couldnt trace anything down that was wrong. he said he had no fuel or ignition. he tried a different ecu and bam it fired up. his bad one was sent out to enthalpy for a tune, i believe this was before he got the other stock ecu. so he gets the one from enthalpy back and nothing happens. he just posted up today saying that they found out what was wrong with it and fixed it. they said it was the ignition input or something of the like was shot. i know i wrote this in a not so good order but hey fuk it, im on webtv and its gonna stay like this. also why i cant go back to his post and find out exactly what enthalpy told him cause it would take 20 mins. thanks a bunch dontbugme for your help.

[Florida240sx]

If that switch on your clutch isn't triggered then the car will do nothing... Hope you figure this out.

[j-z]

welp i got the auto ecu today and nothing. still does the exact same thing, so its not the ecu. i give up now. i might as well change my user name to rusted rotors.

[kouki munster]

I feel your pain man, I can't even drive my car legaly since I'm having problems getting a title for it, stick with it and it will pay off in the end.

[dontbugme]

Well, that sucks. How about checking to see if you have 12V to ground on pins 70 and 113 and then with the ignition switch in the start position you have 12V to ground on 38.

[dontbugme]

If you don't have power at those ecu pins and all your fuses and relays are good I'd try charging your battery, remove it from the trunk and isolate the battery cables back there so they don't touch anything. Next, get a set of jumper cables and connect the pos terminal of the battery to the junction in the engine compartment that the pos cable from the trunk is connected to, i.e., the original battery cable connection. Now connect the negative lead to a good ground somwhere on the engine. Hold your breath, cross your fingers and see if anything good happens.

[j-z]

ill check those pins hopefully tomorrow. im going shooting tomorrow, so i may or may not have a chance. right now shooting is a priorty to alieve some of my stress about this situation. ive got 5 weapons to let it all out through. SKS with AK clip , 12 gauge shotty, 22, 9 S&W, and a 357. yeah its gonna be a real fun day! i had the charger on the batter today for a few hours while i went to pick the ecu up. after i put the auto ecu in and nothing happened i went to take the charger off. that ***** burnt the shlt outta me! i had to drop it down it was so hot. does that mean anything? i think this whole problem started from having the battery on the charger because thats the only thing thats been going on with my car other than sitting there and looking pretty. i havent touched anything, or moved anything for this to happen.

[Florida240sx]

Take a batteyr out of your friends/parents vehicle and hook it up real quick. I just had a problem with my battery connectors. They were only 3 months old. No corrosion on them whatsoever. Swapped them out for new ones and car fired right up. I though it was my starter because all I had was a single click, and then after a couple times I had nothing. Swapped battery terminal connectors and the thing fired right up.

[dontbugme]

Your battery charger should not be getting too hot to touch. Most all chargers have a current regulator that drop the amps as the battery completes it's charge. I have a 15 year old, cheap, 6 amp charger and I can leave it on for days without it getting hot or cooking the battery. I also have a Crafstman charger/starter unit but I don't trust that as much as the cheap one due to all the electronics, blinking lights, switches, etc. If the regulating circuit went on your charger, it could have boiled out the electrolite soulution. I agree with Florida240sx, get a known, good battery from somewhere to try. Hope you had a blast today, I got to get myself out to the range as my kids and father keep asking and it's only 2 miles away. Love to shoot - hate the cleaning afterwords.

[j-z]

yeah i know it shouldnt be getting hot like that at all. that was the first time i had the charger on there since the incident of everything going to poop. its a 1.5 amp charger and my pops said it has one of those regulators on it as well. the first thing i thought my problem was was the battery. thats why i took it up to advance to get a replacement under warranty and they charged it up and tested it and it was good. also, how will some of the things come on that are ignition powered and some things dont. could a battery do that? im not going against you im just trying to figure this out. think maybe something isnt getting grounded? or maybe the chassis is hot causing this? i didnt get around to doing anything at all today. im still gonna try testing the ecu pins, and test the chassis to see if its hot. think that could cause the charger to get so fire hot like it did? i mean this thing felt like i just pulled it out of a bonfire. bish was HOT. im going shootin tomorrow. today was a laaaaaazy day.

[dontbugme]

The chassis won't get hot,it has too much of a heat sink area but you're right the chassis grounds act just like the pos battery terminal except it's the negative polarity. All the current that leaves the pos terminal returns thru the chassis grounds. (Actually, the flow of current could be the other way, but that's a different story). The tests you need to do to determine the cause are simple, if you're careful and complete them explicitly. You need to determine if the ecu is getting voltage, if it is, then you have to check if the relay eccs is functioning to allow that current to return to ground and complete the circuit. See page ec-87 to check that. As for accesories that are working, you can see from the diagrams that many circuits don't pass through the ecu in order to work but the most important ones do. In a nutshell, you have to have power to the ecu then the ground ckt has to be complete for it to work. Get a good battery and hook it up via jumper cables to the original battery connection and connect the negative one to any piece of metal on your engine. GOOD connections for both! You said when you had the engine running it was shaking and running like a diesel, I think you either have a bad battery a connection issue or something came loose, shorts would have blown a fuse.

[Florida240sx]

When I had my grounds not hooked up my car was mising bad. We got 4 of them I think right?? One on exhaust side to the firewall. One from battery to intake mani. One of the injector harness. And I thought there was one more just below that coming from somewhere.... You have a sound sytem in your car? I had to remove my 1500watt rockford amp. When I was stock I was ok. But with turbo if I had it cranked up and it hit a low note it would make my rpms drop down to 200 usually stalling me out....Remove all your grounds. Just because you see it touching the chassis doens't mean it has a good connection. The one for my amp created rust somehow. And it lost it's connection. Looked fine from lookign at it, but when I unbolted it, it was in need of a wire brush. Get that thing running

[j-z]

i dont see anything in my 96 fsm on how to check the eccs relay. i did however take it apart the other day and it looked normal. i also put a relay in there that i knew was good and nothing, but id still like to check if im getting a complete circuit so hook a brotha up. yes i have a 10'' in the back with a 200 watt rockford. i dont even have my headunit turned on at all though cause itll just drain my battery. my battery and amp are grounded to the same place and ill check that. man this electrical shlt is one big pain in the arse! im about ready to have this thing towed somewhere and let them have at it. although how much i HATE to take my car and leave it anywhere, in situations like this its just something that has to happen. ive only took/left my car at one place since ive owned it and that was when i was having another electrical issue (harness grounding out on the head and blowing fusible link fuse) two years ago. if i dont get this fixed with the help of yall, shell be going back to the same place she visited two years ago.

[Kenrik]

MOTHER FVCKER!!!!!!!!!!!!!!!!!!!!!!! i swear if its not one thing its a fuking nother. so i swap everything over to where the maf is on the intake infront of the iacv and get place the straight pipe in place of where the maf used to be. go to start it and it just barely cranks over. now this is weird cause i had it on the charger the other day for like two days. its a motorcycle battery charger so thats why i had it on there for so long. well i figured it for sure wouldve started earlier this morning after i changed everything over. it didnt, so i went and put the charger back on for a few hours and it wouldnt even turn over at all. i figured the battery was shot from having being charged so many times since trying to figure out my problem after the build. i took it up to advance to get a new one and they tested it and said it was good. i put it back in my car and the fans and gauges come on, but no starter coming on or anything. i also noticed that my afc no longer comes on at all anymore, but the gauges and shlt do. note this, the afc is wired into the ecu. i checked all of my ignition fuses and anything that could cause the ignition to not work. i then thought my ignition switch could be the problem. i took that off and apart and everything looks perfect on that, so its not that. DAMN im so PISSED! i was really looking forward to hearing a nice smooth idle today and totally opposite. now im thinking he only thing it could be is the ecu. how it all of a sudden took a shlt i have no idea. maybe being on the charger for so long fuked it up?? i dont know. earlier after i got back from having my battery tested when i hooked it up my afc came on, but while i was trying to hit the ignition a few times on like the 4th time the afc just cut off and no longer comes on. i didnt change anything at all for this to happen. all i did was move the maf, no rewiring of that. i got my buddy george at powerline whos gonna let me borrow an auto ecu tomorrow. if anyone has any inputs on what to look for i would greatly appreciate it as always! does it sound like the ecu could be gone? grrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr

Off Topic.. George is good peoples! I bought a motor from him before.