Dammit Madeline!! (kinda Long and technical)

LittlebittaContact · Dec 25th, 2002, 07:04 PM

I was on my way home from my dads house today, when all of a sudden, my tach went to zero, so as I try and safely pull of the express way, my car hits a snowbank and spins halfway around...grr...anyway, I pop the hood and thier is gasoline pouring out of the air cleaner (this in the injected motor btw) so i know the fuel pump is working, I turn the key off and this stopped the gas. just to be safe i d/c the battery, which was a good thing I later find out. I get it towed to my grandpas house where I take the injector out, it looks ok, so I put it back and tell my mom to turn the key on, still the pump is just pumping gas like thiers no tomarrow. so I get out my bible (which is always in my spare tire area) and I unscrew the ecu and put it on the pass. floorboard, turn the key back on and the red and green LEDs are both on, But how can I run the test! I can't turn the key on without the risk of making a campfire! Anyways, I took the metal cover off the ECU and WTF!!! part of the ecu was melted! Even turning the key off didn't help, it was still getting hot so as quick as I could, I pulled the harnesses out of the ECU and d/c the battery again just to be safe.

Now, Heres the real Dilemma, thier isn't another 88 Sentra SE in any of the local yards, so I have to buy one reman, no big deal, BUT...

how can I be sure that the ecu just went bad, or that a wiring problem didnt melt the ecu?!?!

Heres all i know for sure: When it went bad, the ignition cut out, I couldn't even 'pop the clutch' to get even a spark out, so I think the ecu cut the spark, but it kept the fuel pump just pumping and pumping, you know how usually when you turn the key on, but don't start the car, the pump will pump for a second, then turn off until you start the car? Well mine just started pumping and never shut back off!

What a F'n mess! And I'm no good for electrical. I dont mind shelling out a couple hundred bux for my baby, but I dont want to have to shell it out 4 times before I find the wiring problem, if there is one.

Thank you for reading, lets put our heads together and see if we can fix Madaline!

Crazy-Mart · Dec 26th, 2002, 04:46 PM

your ecu is shut.... the programming sends the 2 sec delay for the pump to pressurize... if it still pump before you start, the ecu is shorted !...for sure !!.... get another one from any 87-88 sentra with manual tranny... be sure its a manual tranny!!!...

the wiring itself wont short the ecu... well it as a fuse on it so it should blow out before the ecu.... you probably have some bad condensator on it that went capout !!... does it smell like rotten eggs ????... if yes, those condensator are gone... and the pcb is gone too.... nothing can be done with it... those thing are filled with some kind of acid that just fuckup the PCB... there isnt much to do with it !!... youll have to change it !!

...

Crazy-Mart · Dec 26th, 2002, 04:47 PM

also ... the ecu from any classic up to 93 should do if im not mistaken....(as long as its the e16i motor)

LittlebittaContact · Dec 26th, 2002, 07:15 PM

Well, that is mostly good news, however, my next question is this...

What should have blown before the ECU? I mean on the newer cars they all have Powertrain Fuses and Relays, Ours do too somwhere....dont they? And if it does, where is it, because i want to kick its ass and it owes me $297.40

Oh, and what is a PCB?

Dec 26th, 2002, 09:11 PM

PCB is short for Printed Circuit board. IE, the circuit board inside your ECU. Don't worry about smelling it. It's toast. There are fusible links under the hood that should blow, but I think they are way more powerful than that ECU circuit board is. Generally, if something inside the ECU shorts out bad enough to do that, a fuse is only going to prevent it from melting, you'll still have to replace it. And the reason your fuel pump is still going is probably because your pump was running when your ECU went tits up, so the switch inside the ECU that turns on the pump got stuck in the on position. (Best guess..)
There are probably 10-15 88 Sentra's at my local junkyard, if you want me to go fetch you a computer, lemme know, and I'll find out how much they want for one.

LittlebittaContact · Dec 27th, 2002, 07:44 PM

That would be awsome, I tried to get one from Blown, but his was Bad, The Numbers off the old one are A11-A30 B34, but Blowns was a little different, the only thing that matters is that its the Fuel Injected engine, and Manual Trannsmission. Hit me up on yahoo dude so we can chit chat!! Peace!