I have a 98 SS and I've recently encountered some really weird electrical trouble and I was hoping to get some opinions about what it might be. First off, one time when I went to start my car, I come to find my radar detector (plugged into the cigarette outlet) turning on and off continuously. When I try to start my car I can hear the solenoid on my starter click a few times, like it's engaging then disengaging repeatedly. The starter itself wasn't cranking, but then all the sudden the starter just caught and the car fired up. What was weird though is that somehow it had reset my ECU so that my clock was reset, my trip odometer reset, and for some unknown reason to me, my engine was idling at like 2500 rpm and surging. So I drove around the block, with my engine basically pulling me by itself. I stop, kill the engine, reset my ECU manually by pulling the PCM BAT and PCM IGN fuses. My car fired right up and idled fine. Then about a week later, the car did the same thing when I tried to start it, only without the weird high idle and engine surging. Over the last week it has happenned with increasing frequency and severity, with the high idle and engine surging happenning only some of the time. It also got more and more difficult to start, i.e. the weird starter problem would last longer and require more attempts to finally lock up and crank my engine. Finally, two nights ago, my car wouldn't start period and my battery appeared to go dead after many attempts. The next day I try jumping the car, but the problem seemed to be in the starter. I could hear the engagement solenoid firing rapidly, like click click click click ... really fast. What I also found odd was that even when my car was hooked up to another battery on a running car, all the the electronics in my car were responding as if my battery was dead. My windows would barely move, my instrument panel was really dim, door locks lethargic, etc. After numerous attempts I actually began melting the insulation on the jumper cables due to excessive current draw even though my starter wasn't even turning, making me think something might be shorting intermitently when the solenoid tries to engage the starter. Unable to get the car started I went to autozone, where I tested the battery, which turned out to be fine, and I also went ahead and bought a starter, thinking I could at least just try replacing that. With the battery fully charged, I checked continuity on all my main power connections and checked the voltage in various places in the car. Voltage was pretty solid all over without my battery being hooked up to another. With my multimeter measuring voltage across the fuse box, I noticed the voltage started at about 13 volts and then climbed to about 18 while I did nothing to the car, probably a meter thing (they can be quirky). I tried to start the car then and it fired up as if it hadn't given me any trouble previously. I promptly drove it home, where as soon as I stopped, it would not start. So I have a starter and will try replacing it tomorrow, but I'm concerned with the other problems. I don't understand what could be causing my ECU to freak out when this happens so that my idle is messed up and the engine is surging. I also can't figure out while my battery meter appears dead and all the electronics in my car act as if the battery is dead even though the battery is maintaining 12.5 volts and tested fine. I'm worried there is some more deeply rooted electrical problem, but I'm hoping that somehow the starter is the culprit. Just as a side note, I haven't thoroughly checked the starter relay, but it appears fine from the outside and all the fuses are fine. Sorry for the length, but these problems are weird and I wanted to be as detailed as possible. Thanks in advance.

Tim James

 

I think thats a low battery problem. Leaving your detector plugged in will cause you to loose some battery power depending on how long you leave your car with the detector plugged in. The surging is the ECM trying to get the battery charged up, and if your driving the car to say Autozone to get it checked it probably charged itself back to life on the drive over there and thats why it checks good. But starting a car takes alot of power from the battery, so if you got it checked at autozone (which drains your battery a little bit) then you just got enought power to start while your there, then you drive home and you kill it, then the battery didnt get charged up enough to start it yet again. When your car fails to start, and your jump starting it make sure the cables are thick otherwise you will start seeing things melt and wires smoking. Try leaving the detector at home for a couple of days and see what happens.

 

It sounds to me like you have a bad ground from the battery to the car, or a bad ground on the starter. If your multimeter will read up 10+ amp current then disconnect the postive terminal and hook up the meter leads to the battery + terminal and the other end to the positive wire. See if there are any current drains. If there is then pull fuses one at a time and see where the drain goes away. That woud be the problem area. I would also do conductivity test between the negative post and a ground on the car with the resistance setting on the meter. It should read 0 if the ground is working.

 

Thanks for you help so far guys. I know it's not a low battery, I took the battery out of my car to test it and it has help 12.5 volts every time I check it. It has never gone low. This morning I dropped my starter and had it electriconically tested at Autozone and it tested just fine. I went ahead and bought a new starter relay, just in case that could be the culprit. I'm going to make sure the starter is getting good voltage using my multimeter without the starter hooked up. My multimeter does go up to 10 amps, but's it's a reasonably nice one and I don't want to fry it, although the fuses inside the multimeter should blow before and damage does occur. So StrokedLS1, you're saying I should see if I'm getting any current drain from my battery when my car isn't running or trying to be started. I understand how a faulty connection somewhere could be draining my current away from the starter and any other electrical equipment, like a short would, so that could be a valid explanation. I guess the best bet would be to try and start the car without the starter in and check for current drains, right? Thanks again for your help guys.

Tim

 

The starter uses like 150+ amps to start. I was saying with the car off and everything turned off see if you have any drains. Check all the grounds to confirm they are tight with good metal to metal contact. Check the voltage at the battery while someone else starts it. Check the resistance on the postive cable at the battery to the starter. I can't really trust what the guy at autozone said because they told me a battery was no good that was fine after an over night charge. Alot of those guys don't know **** about cars in general that work at those places. Electrical gremlins can be a pain. I would try another battery if you have one lieing around.

 

Got some more info regarding the problem. After testing and re-installing my starter the car started perfectly for about 5 starts. This morning however the problems came back. What's actually happenning is that the car's power is intermitent. For instance, the solenoid on the starter rapidly engaging and disengaging. Also, I noticed that the fuel pump relay was clicking on and off rapidly. I replaced it with another relay and it still clicked on and off. Then I noticed even without my keys in the ignition or anything, the lights in the car were going on and off. It is clear to me that something in the car is draining current from the battery, like a short or a faulty component. The problem is it could be anything. I want to try and find the current draw, but I'm not sure the best way to do it. I suppose I could test current draw from the fuse box across each fuse and that will tell me if any of the electronic components are draining the current. I just don't know what to do if it's not a component, like a mechanical short or something. If anyone has any suggestions about what to check or how to check it, I'd appreciate it. Thanks for you help so far.

 

Check the simple stuff first - all your grounds, check connectivity of wires and connection and ESPECIALLY check your PCM and BCM. A recent customer had a '98 Z that was doing similar items you describe and then when hitting bumps, the car was shutting off...and then back on. FIX - disconnect PCM, sprayed with elect. cleaner, connected and tightened to bracing with reinforcement under it so it wouldn't wiggle, jiggle or move when going over a bump. The car hasn't acted up or shut off since.