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bodega1027
05-22-2009, 11:20 PM
So here's a weird one for you guys...

Some of you will probably remember all the starting problems and stalling problems I've had in the past. Most of the stalling problems were solved with a new alternator (although once it a blue moon it still stalls when I'm slowly creeping in reverse, or when I let it sit and idle for awhile then shift to drive... and no, it's not the TCC, so don't ask! :lol:). All of the starting problems (which were characterized by the car having NO response when turning the key even though the ignition switch was good) were solved by wiring a relay into the starting circuit, so that the wire that USED to trigger the S-Terminal now triggers a relay, and the relay takes power from the battery to the S-Terminal (this was done because, after exhaustive testing and changing of parts, I couldn't figure out why my voltage was always SO low at the S-Terminal... and for the most part this did the trick!).

So one day, not too long ago, I was sitting in a parking lot waiting for my wife with the car running, and when she got in after maybe five minutes of idling, I shifted into reverse and the car died. When I went to restart it, it wouldn't respond for the first time since I put the relay in months ago... I was getting power to the S-Terminal (which I know for a fact, because there's an LED indicator in my cab wired to it). I didn't have a voltmeter to check, so I don't know how much though. I didn't know what to do, so I just sat and tried to start it every couple of minutes. The starter motor and solenoid are both almost brand new, but I still tapped it with a screwdriver a couple of times to try and get a response out of it. Nothing worked.

Finally, while messing around, I switch the AC to "Vent"... and it started. And I thought, "How weird..."

A couple of weeks later I'm in another parking lot... I've got to run into the store, but I've got my wife and daughter in the car and it's like 100 degrees out here, so I go ahead and let the car idle so I can leave the AC going. I get back to the car after maybe five minuts, and I get the same stall and the same no start. So purposely this time, I switch the AC to "Vent" and IT STARTS.

Now. Finally. On Monday, I had to jump out of the car for less than three minutes to unlock a driveway gate at my workplace. I get back into the car, and it stalls (this sounds like a lot of stalling, I know... this is probably the only three times it's stalled over a period of 6 weeks). So I go to restart the car, but THIS TIME I get a little sputtering, and my headlights, dome lights, dash lights, and stereo all go dead. I rotate the key back and forth, and everything remains dead. So, just on a hunch, I switch my AC to "Vent" and all the pwoer comes back up and the voltmeter is still reading 12v on the battery. I try to start it again, and again everything goes dead. Finally, I try to start it with a screwdriver to the S-Terminal, and all I get is a little sprinkling of sparks, then a dead car again.

I had to leave town, so the car has been sitting all week, but when I got back today the car still wouldn't start.

I'm THINKING that the problem is some bad wiring somewhere between my battery and my starter, so I'm going to try to find some bare wire or burned up connections this weekend. I think I should try to find anywhere where the wiring can be affected by the position of the vents, too.

Can anyone think of anything else it could be? Ignition Module? ECM? H1N1?

CieraSL92
05-24-2009, 01:43 AM
I'm not sure if the ECM will command the A/c clutch to engage if it sees 0 rpms, but the clutch is a pretty big drain on the electrical system. I didn't read it in full, but since you can start it with it in vent where the ECM wouldn't command the clutch

how old are your battery cables

(will reread this later, im actually multitasking x30)

turbokinetic
05-24-2009, 02:10 PM
Not the ignition module.

GOT to be bad wiring or battery terminals.

I had a positive battery cable go bad with no outward signs of damage. The starter was turning slowly, and the engine would "kick back" against the slow starter and broke the aluminum nosecone. The replacement starter still turned over weak. Using a voltmeter, I tested voltage drop from the battery positive terminal to the starter, and found out I was only getting a 5 to 7 volt drop across the positive starter cable!

Replacing that perfect-looking cable fixed the problem. I took a knife and cut the insulation of the cable, exposing the copper wire. Nothing was left but a green, powdery, corroded mess; encased in a perfectly clean, undamaged sleeve of insulation.

Somehow battery electrolyte had seeped into the cable through the factory-installed positive battery terminal, and "wicked" into the wire.

What you describe is a CLASSIC sign of a bad connection, high resistance, and voltage drop.

First thing to do is thoroughly wire-brush the battery terminals (the flat surface where the cable bolts onto and makes contact) and the battery cable ends, AND THE BOLTS that hold the cables to the battery.

Connect the voltmeter neg lead to the battery negative terminal bolt, and touch the engine with the positive lead. See what kind of voltage drop reading you get when attempting to start the engine. One volt is OK more is bad.

Repeat the same test between the negative battery bolt, and the car's body.

Next test would be the same thing with the positive. Put positive test lead to the positive battery bolt, other lead to the starter positive stud. See how much voltage is lost when attempting to crank.

The A/C clutch thing is interesting - it only uses a few amps; but it does ground through the engine.

Check the battery cables and ground cables first.

Thanks,
Dacid

bodega1027
05-25-2009, 12:19 AM
Will do! I'm actually on my way to it right now. The battery cables came with the car, and look like the original 1991s - one test I forgot to mention was I check volts at the solenoid battery terminal, and I was reading like 11.75 when the car did nothing, but it would drop to 5 volts when actually starting it. Thanks guys!

(Also, sorry about the long winded post... I have a hard time knowing where the line is between being detailed and rambling haha)

bodega1027
05-25-2009, 02:01 AM
I didn't have an assistant to perform the volt test the car with me, but I did cut open the sheathing in my negative cable, and found that blue/green/white corrosion CAKED inside of it, all the way down. I think when I head to Autozone for some cables I'll bring my battery with me too to have it bench tested, but it looks like those cables will need some changing regardless of whether or not its my problem.

Thanks for the tip!

bodega1027
05-28-2009, 07:57 PM
Yup, changed my negative cable and the car started right up. It's was running fine... for a day. This morning, however, the car wouldn't start. I've got 12.5 on the battery and 12.3 at the starter, but for some reason I'm not getting any power at my S-Terminal when I turn the key (the dash lights do come on however, indicating a probable good ignition switch). The neutral safety switch, solenoid, and starter motor are all relatively new and I double checked to make sure all my grounds were tight - after work I'll double check to make sure I hadn't knocked any wiring loose; there's also the above mentioned relay wired into my starting circuit because of a poor voltage problem I was having at the S-Terminal previously - I've got a theory that replacing the negative cable has returned my starting circuit voltage to normal, and that the normal voltage was enough to zap the relay, but I'll know for sure soon.

bodega1027
05-29-2009, 06:19 PM
Nope, wasn't the relay. Gonna check the rest of the wiring this weekend and see if I can pinpoint where the S-Terminal power is cutting off at.

bodega1027
05-30-2009, 11:03 PM
Turns out when I messing with my cables I just pulled the S-Terminal wire out of a butt connector - works fine now!

turbokinetic
06-01-2009, 08:31 PM
Turns out when I messing with my cables I just pulled the S-Terminal wire out of a butt connector - works fine now!

SO!!! The root cause was..... Prior Repairs performed by an IDIOT!!!!!

I wish everryone who uses a butt connector under the hood of a car had an additional 10 of them forced up each nostril!! :rant:

David