ecu making noise... x_X

[psychedelicbeats]

my ecu making a noise. well to start off, my car isn't running properly. for some reason, when i go WOT the car will sputter and sometimes die. sometimes when it dies, the ecu will make a noise, like a buzzing sound. this really doesn't sound good, and "might" be the reason why my car is dieing. i have an s14 auto ecu on a coverted manual s14

[SimpleSexy180]

is your EGR functioning correctly? i get a buzzing sound from my ecu too and i think its becuase of my code 45 it throws out >_<. Check to see if your ecu is throwing a code.

[psychedelicbeats]

ok... my fuckin ecu is now fried.... =(

[SimpleSexy180]

lol what happened??

[jdm538]

damn musta been bad wiring

[Maeda]

Buzzing is most likely the ecu on relay.... You probably had a short~! Whip out the multimeter and start testing.....

[psychedelicbeats]

my ecu is on relay =( short?! ahhhhh maeda come to my house and fix this!!!! i'll pay you for your services!

[Maeda]

Sadly I'm pretty sure i'd be a stumped as you are. The only reason I got my ecu relay to stop buzzing was because I knew where the short was.
Try and swap ecu's with a friend to see if that does the trick. If it doesn't i'm betting its wiring like i've mentioned to you before.

Good luck though.

[psychedelicbeats]

i've a feeling it's the ecu itself. does the relay go buzzzzzz when an ecu is toast? i unplug the ecu, and it goes off. when i plug it in, it goes on again. ecu may have caused my recent problems: the problem i had before with the WOT was because of an electrical problem. the car stumbles and feels like there's a bad maf, but i can still rev up to 6000rpms. i checked the maf and it's good. i've checked the tps and it's good. there's fuel going in the lines, but i'm still not sure if the egr system is causing this. there's a buzzing noise where the egr solonoid is located(inbetween the intake manifold) i went to another s14 and see if that could be a problem. i hear a noise on the other s14 as well, but not as loud. it honestly sounds like what the ecu sounds like. like a relay going zzzzzzzzzzzz. the solonoid itself does this sound for a second when the key is turned to ACC-2. back to my ecu. it's still buzzing after cleaning up all of the wiring i could possibly think i had left "dangling around". the relay for the ecu still goes off. i've yet to have an ecu to test, but when that comes, i'll keep whoever that is also concerned, informed. other than that, i would like some more insight with this situation. thank you everyone in advance.

[radhaz]

Try and swap ecu's with a friend to see if that does the trick. If it doesn't i'm betting its wiring like i've mentioned to you before.

Be advised if there is a short in the car that fried your ecu it is entirely possible that plugging in another ecu just to check could result in catastrophic failure of the ecu being swapped in. Search for a ground before you hook up any known good ecu's to prevent having to buy another ecu for someone.

[idlafie]

i've a feeling it's the ecu itself. does the relay go buzzzzzz when an ecu is toast? i unplug the ecu, and it goes off. when i plug it in, it goes on again. ecu may have caused my recent problems: the problem i had before with the WOT was because of an electrical problem. the car stumbles and feels like there's a bad maf, but i can still rev up to 6000rpms. i checked the maf and it's good. i've checked the tps and it's good. there's fuel going in the lines, but i'm still not sure if the egr system is causing this. there's a buzzing noise where the egr solonoid is located(inbetween the intake manifold) i went to another s14 and see if that could be a problem. i hear a noise on the other s14 as well, but not as loud. it honestly sounds like what the ecu sounds like. like a relay going zzzzzzzzzzzz. the solonoid itself does this sound for a second when the key is turned to ACC-2. back to my ecu. it's still buzzing after cleaning up all of the wiring i could possibly think i had left "dangling around". the relay for the ecu still goes off. i've yet to have an ecu to test, but when that comes, i'll keep whoever that is also concerned, informed. other than that, i would like some more insight with this situation. thank you everyone in advance.

**WARNING**..long reply...read at your own risk...you've been warned!!

PB....
If your ECU was toast your relay would NOT be buzzing. Your ECU would not be working at all!! Try a little test....pull the passenger side kick panel, plug your ECU into the harness (making sure you can see the LED test light on the front of the ECU while you are sitting in the driver's seat of the car), then turn your ignition switch to the ON position...DO NOT START THE CAR!!...While you are turning the ignition switch to the ON position, check both your dashboard AND the LED test light on the ECU. Both the Check Engine Light on your dashboard AND the LED on the ECU should light up. If they do, then your ECU is working. If the Check Engine Light AND the ECU LED don't come on, then check to see if you are getting power to your ECU. You'll have to pull a FSM to find out which pins provide power to the ECU on the ECU wiring harness. If the wiring harness checks out okay, then take your ECU, plug it back into your harness & put your ECU into Diagnostic Mode. If Diagnostic Trouble Code 31 shows up, THEN your ECU COULD be dead. Take your ECU to another S14 and try starting that S14 with your dead ECU. If that other S14 starts, then it's NOT your ECU...

From what you describe about your car stumbling as you drive it, chances are you may have a damaged wiring harness. You mentioned previously that you had done an auto 2 manual swap on your car. Did you hoist or tilt your engine when you did the swap? It's possible you could have damaged the main wiring harness or subharness connector during the swap, (possibly a bent pin or loose connector). I had this problem occur to me years ago when the dealer removed my tranny to change out a bad release bearing. Unknown to me, the dealer screwed up my wiring harness while removing the tranny. I found out the hard way while on a road trip 400 miles from home after my car died on me at 80 miles an hour while driving down a big-ass hill on the 580 fwy coming into Dublin. Prior to the trip & during the trip, the car ran fine. It was when I was coming home that my car started acting up big time ...stumbling...dying etc. Luckily for me my car crapped out at the freeway exit next to Dublin Nissan. I was able to limp off the freeway & directly into the dealer's service bay. Luckily for me I had a damn good service tech. It still took him over 2 hours to figure out what the source of my problem was. The ECU would throw a code one minute then be fine the next...and the codes were all different!!...when he accidently bumped my harness while testing the other components he realized what the problem was...the harness & not the connectors...

Anyhow, check the attached link - this will give you an idea as to what I'm talking about. ALSO...cut & resolder a new grounding grommet at the point where your engine harness connects to your engine block - above the O2 sensor by the brake booster. I pointed it out to you last time we talked.
Anyhow, here's the link.....
http://www.alldata.com/service_provider/techrx/2000/20000713.html
Oh...don't let the information on the webpage fool you. Although it talks about the KA24E motor and 90-95 Nissan trucks, the KA24DE wiring harness will have the same type of metal crimp connectors. You're gonna have to remove the electrical tape & wire wrap surrounding the wiring harness and check all the metal crimp connectors on the harness. It's gonna be a pain in the ass to do, but it should fix your electrical "gremlins"

Anyhow, hope this helps...
ID

PS: And if you don't already own a FSM for your car, then download one from here...
http://www.ffdet.com/members/rich/Nissan/nissan.htm
http://www.zeroyon.com/TheSite/techservice.html

[psychedelicbeats]

i talked to sam when we met up. indeed you have a lot of points there. i still need the manual ecu anyways so i took it from sam. anyways, i already know it cannot be the ecu, but my AT ecu is pretty much shot or either useless to me now(need to get rid of DTCs). it has to be a short circuit. something is not properly grounded. there should be a series of ground wires for the starter, alternator, albeit most of what's down there, somewhat similar to what's on the page you've shown me. i'm pretty sure that is the case as well. might as well get my wiring done right the first time right? i have a fsm ready right here and will be reading most of the harness problems. i'm sure i have not touched any wiring in the engine, but i will double check for any ground touching a power wire (and vise versa). thanks for the insight diego. good website you gave me! you're a good man

[Maeda]

Be advised if there is a short in the car that fried your ecu it is entirely possible that plugging in another ecu just to check could result in catastrophic failure of the ecu being swapped in. Search for a ground before you hook up any known good ecu's to prevent having to buy another ecu for someone.

Doh! Sorry bout that... I wasn't thinking straight....

Did you get this thing going yet? Looking for shorts sucks!

[psychedelicbeats]

ok i plugged in the manual ecu that i got. i checked fueses relays everything u can think of(except for the ascd and eccs relay next to the ecu) before i plugged it in and it's all okay. of course, everything done while taking neg bat terminal off. everything is plugged in, and i turn the key to acc2. there's no check engine light. also scanning for DTCs the check engine light didn't go on. palmstein (free version of pocketlogger i guess)could not get into the computer either. i've felt most of the wires around the engine to where i can get to and i don't feel anything going hot. the car will not turn over from what i understand if the ecu is not functioning properly. i will check the accd and ecu(Eccs) relay after this and see what i can come up with. after that, if all checks good, i'll then look under the car once again for any bad stuff. then i'm gonna do what diego told me...


more insight appreciated =)

[psychedelicbeats]

ok my power door locks don't work. also the warning buzzers for the ignition key does not go off either. could someone route me to its electrical connections? fsm is all over the place...

[psychedelicbeats]

i've come to find out that my smart entrance control unit is busted.... damn. well that solves one problem..

edit: got my smart entrance control unit fixed. also, the car starts and idles fine(at ecu). i didn't want to put it in motion though because of what has happened... also i immediately unplug the ecu after shutting it down due to running a risk of shorting the ecu. i still need to diagnose because sometimes check engine light go on and sometimes it don't. i'm gonna proceed with the possible engine harness problem tomorrow.

at least i found a possible list of problems off of mitchell (chornological checklist) for " Lack of power / poor acceleration (stumble) "

check engine mechanical condition
check fuel delivery
check fuel pump circuit
check fuel pressure regulator
check fuel injector circuit
check fuel evaporative emission circuit
check positive crankcase ventilation (pcv) system
check idle air control (iacw)-air regulator
check idle air control valve-auxiliary air control (iacv-aac) valve circuit
check idle air control-fast idle control device (iac-ficd) circuit
check ignition timing and ignition circuit
check egr-canister (egrc) control solenoid and circuit
check exhaust gas recirculation (egr) system
check main power suppoly and ground circuits
check radiator (cooling fan) circuit
check a/c circuit
check camshaft position (cp) sensor circuit
check mass airflow (maf) sensor circuit
check front oxygen sensor (o2s) circuit
check throttle position (tp) sensor adjustment and circuit
check engine coolant temperature (ect) sensor circuit
check vehicle speed sensor circuit
check knock sensor (ks) circuit
check park/neutral position (inhibitor) switch circuit
check pcm inputs/outputs and pcm.

[psychedelicbeats]

i have a question.... could a bad connection to the crankshaft position sensor have caused my idle fluctuation?

and about my ecu, the manual one i plugged it in for a test, but there's no check engine light. i can't pull any diagnositc codes. however i do see the LED flash immediately after turning the key position to on. how come my ecu isn't working? sam (c-tune) handed me the ecu, and i hope he didn't give me a bad one...

[idlafie]

i have a question.... could a bad connection to the crankshaft position sensor have caused my idle fluctuation?

Nope....all it will do is cause your Check Engine Light to flash on & off on your dash. Your car will still start & run. Idle fluctuations problems are caused by other stuff.

and about my ecu, the manual one i plugged it in for a test, but there's no check engine light. i can't pull any diagnositc codes. however i do see the LED flash immediately after turning the key position to on. how come my ecu isn't working? sam (c-tune) handed me the ecu, and i hope he didn't give me a bad one...

Call one of your buddies up that have a S14. Take YOUR "dead" ecu's down to their house, unplug their ecu's from their car, then plug YOUR "dead" ecu's into their harness & try starting their car. Chances are YOUR "dead" ecu's are still good. It's your wiring harness that shot!!

You're going to have to take a voltmeter & continutity tester to your harness & double & triple check your harness to make sure you are getting power to the ECU & that there are no shorts or loose wires in the harness. Troubleshooting wiring harness problems are a MAJOR BEYOTCH!!...why do you think I hate 'em with a passion.....

Good luck bro...you're gonna need it!
ID

PS:
Hopefully this will point you in the right direction. Pull out your FSM to verify that the info is correct.
http://www.emergent.com.au/200sx/s14-ecu.html

[psychedelicbeats]

wow i've noticed a lot of electrical problems under tech talk lately. this is how dreadful nissan has put our electrical situations to... =(

i think i found the problem. when i hit the windshield wiper up and down with the key on the on postion, the rpm needle bounces! whoa! wth. with the car on and on the street, before i begin to get the car in motion, i hit the windshield wiper, and the car stops as if the ecu had burned out (it's not burnt though, i've done this several times). could the tachometer actually shut down the car if it is being shorted by a the windshield wiper (and vise versa)?

i want to also note if the SMJ is somewhat related here