Car up and dies (no lights, hazards, any electrical)

Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
In my agitation this morning, I accidentially posted this to the moderated tech tips thread I was reading earlier. Forgive me for I know not what I do :p

1989 Turbo, 7MGTE, no mods. California car, dry climate.

In the last couple of days, my car has been developing a problem that has been getting increasingly worse. It has a habit of not starting, and/or dying at random. When it's in one of it's snits, you'll get into the car, everything will be normal, stuff will beep, lights will come on, stereo will come on in Accessory or on, but when you turn the key to start, it just up and dies, no relays clicking, no anything, no lights, no power at all (not even hazards.) until you get out and wiggle the negative battery terminal, at which point the car will start, but not properly idle. It'll idle roughly at around 500RPM, then just get slower and slower until it stops (over a period of about three seconds.) As long as you prevent the engine from idling, it'd be fine. Last night, I replaced the battery's negative terminal, because my old one was corroded and nasty (standard crappy pressed metal negative terminal) crimping the two ground straps to it. Car started fine, idled normally, ran fine, until I got almost home, and it just died. No fuss, no muss, just dead. got out, jiggled the battery connector again, and was able to limp it home once more (would not idle, etc.) I attributed this to a crappy job done in the dark, with inferior tools, and a flashlight between the teeth. This morning, I went out loosened hte clamp, stripped my ground straps back a bit further and clamped them down much more securely. I'm fairly confident about my job there. Get in, start up, car starts, runs, idles normally. I get to a stoplight on my way to work, car dies in the same manner. Get out of the car in a panic cos I have no brakelights, hazards, or again, any power at all, and wiggle negative battery terminal again, hear "key in ignition" to confirm I have power again, car starts, but again, will not idle properly.

I have a feeling that my ground is still bad somehow, but what on earth would cause it to be this intermittent? I've hacked off the old battery connector, and put on a new one, but I still jiggle the wires leading to it to get power to work. Why on earth would all the power in my car die completely until I jiggle the cable? Has anyone seen anything like this before? Could this be indicitive of a bigger problem?

I'm going to replace my ground straps unless someone has a better idea. I'm no EE, but is it possible that with the high current loads on them, they could have rather high resistive properties by now?

Thanks for your help, this is a bit of a worrisome (and rather dangerous -- no power == no hazards when it fails, until I get out and massage the negative terminal just right.

Slightly offtopic: Anyone wanna buy an '89 turbo targa 5spd that won't pass smog? Take my dog, Please! *grins*

Cheers!

CCC
 

bassjunkiens5

New Member
Nov 25, 2008
31
0
0
Tenn
I think you're on the right track. Either the ground cables are bad/corroded inside the wrap, or, the terminal you bought is for a pos instead of a neg post which would be bigger and not clamp properly, or you have a bad battery overall. Sometimes a battery will hold a perfect charge untill a load is put on and the CCA's will drop to nothing. Check the battery for swelling also.
 

arizzle

Lov'in the boost.
Nov 1, 2006
996
0
0
36
burnaby, BC
well are your battery terminals clean? and same with your cables? if not use warm water and baking soda and a tooth brush to clean them, also do you have battery hold down? if not that can also cause your cable to loosen from all the vibration. thats what happened to my car once on the hwy!
 

MK3.0dudeman

brian L.
Mar 12, 2007
1,628
0
0
North Jersey
replays the terminals and if anything just get a new ground.

your idle problem is because the e.c.u. reseted and is trying to relearn everything and than after a it runs for awhile and you go for a nice drive it idles fine right?

just a little fix will do the trick
 

Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
Righto, I just got fed up and went ahead and replaced all my grounds, but found that there was a little positive cable that was shorting as well, and keeping my car from starting, presume that was the ECU pos wire. Fixed that, and now electrical works fine, car cranks fine, but doesn't start.

All underhood fuses and relays check out fine, I'm just not getting fuel or spark. This is really beginning to get aggrivating, as now I'm stranded at work, and can't leave :p I'm trying to remember where on earth the ECU code listing is in the TSRM so I can see if my ECU is complaining at me about something. we'll see what I can find out, but this is rapidly becoming a pain in my arse :p

Cheers!

CCC
 

Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
Meanwhile, back at the ranch...

I put back on the original ground (with the new battery connector I obtained previously) and got the same results. I thought I may've attached my new grounding cable to a point where it wasn't grounding properly with the block, and the plugs weren't firing. I also replaced a fuse I'd managed to lose in testing, and it's throwing a Code 12 at me, RPM signal. "No "NE" of "G" signal to ECU within 2 seconds of cranking." What could I have fried in my adventures of replacing my grounding cables, and reconnecting that bedamned positive wire? My ECU seems to be alive and able to throw codes, so I don't think I fried it, but that seems to be the only thing for the moment. Anyone know what else could've blown up along the way? It started and ran gimpily (ie,would start up, but had to keep Revs above idle to get enough juice to keep it running because of intermittent battery connection) until I fixed the wiring harness, now it cranks like a champ, and the electrical systems all work, but it's throwing code 12 at me, and won't fire.

Help is greatly appreciated!

CCC
 

toyotanos

What will we break today?
Staff member
Super Moderator
Nov 29, 2008
2,841
2
38
Coon Rapids, MN
That code specifies that your "G" or "NE" circuit is not sending your ECU the engine speed/position. That signal is created in the CPS, so check the cps connector first, just to make sure it's plugged in securely. If it's OK, you're going to have to check the pickup coil's resistance to make sure they're not open or shorted. If they're OK, you'll need to make sure the wires to the ECU are OK. The TSRM has a specific inspection procedure for the coil inspection, and you'll need a good multimeter. Page IG-16.
There is also the possibility that your "sta" signal wire to the ECU is open or shorted. This wire sends the ECU a signal to indicate that you're cranking. This procedure is on page FI-63 of the tsrm.
The computer needs all these signals to start the car, so make sure it has them!
Hope this helps.