its an 88 TII with no mods
I had the CD player, and headlights on at the time...
I was coming home on the freeway and the car seemed to be running poorly. It was very difficult to keep the car at a constant speed, it would either accelerate heavily or decelerate. Then the CD player started turning on and off. So I'm wondering what the hell is going on and wouldn't ya kno, the car just dies. 0 RPM, but I can hear fuel going in when I depress the pedal.. wtf... so I pull off on the side and a cop shows up.

I tried to start the car but it wouldn't even crank. I hooked some jumper cables up and tried it and it turned very slowly at first. I was able to jump start the car and it seemed to run just fine. It idled ok and everything. Then I started to pull out onto the freeway and I had absolutely no power. The car was shaking pretty bad and the lights were dimming very quickly. I was in 2nd gear, flooring it and couldn't get it to go over 30mph. So I pulled over again and called a tow truck.

Now my question... what is wrong with my car? I'm guessing an electrical problem but I don't know where to really start. I checked the alternator belt as soon as I got home and it seemed fine.

Any help is appreciated. Thanks.

 

bad alt or charging system.

 

make shur that the bolt on the top of the alt is tight something like that hapened to my brothers rx7 and it was just that bolt lose

 

that's happened to me also
just check to make sure the plug leading into the back of the alt is in tight, and snapped in or whatever
and double check the nut that keeps the other wire leading to the bolt is tight
then double check the belt to make sure it's tight
afterwards charge your battery, or jump it, start the car, check the voltmeter or use an aftermarket one, the one in the instrument cluster is kind of shitty, if it reads around 13-14 you're in good shape, if it reads twelve or less you may need a new alternator or a rebuilt one
new ones at autozone are like 150 bucks, for a stock s4 alt, cranking 70 amps
not sure about the tII, but my NA one was that price

good luck

 

that's happened to me also
just check to make sure the plug leading into the back of the alt is in tight, and snapped in or whatever
and double check the nut that keeps the other wire leading to the bolt is tight
then double check the belt to make sure it's tight
afterwards charge your battery, or jump it, start the car, check the voltmeter or use an aftermarket one, the one in the instrument cluster is kind of shitty, if it reads around 13-14 you're in good shape, if it reads twelve or less you may need a new alternator or a rebuilt one
new ones at autozone are like 150 bucks, for a stock s4 alt, cranking 70 amps
not sure about the tII, but my NA one was that price

good luck

 

Check to make sure your battery cables are sound, and that the positve cable isnt grounding out. I had a similar problem where my stereo would start turning on and off and my lights dim, it was because the postivie bat. cable was grounding out on the steering rack

 

my stereo would turn off when i put my head lights up it turned out it was just the acc wire i used for some reason went bad im not shure why but i thank it had to do with the wireing problems they have

 

wiring problems??? you mean who ever wired your stereo did it micky mouse style???

If turning your headlights on kills the stereo, either you have a bad alt or bad alt connections, or your stereo is too powerful for the current alt/battery set up in the car.

Of course most Japanese cars have small grounds, (the RX-7 being no different) and they will often need to be upgraded wigth any sort of additional electronics, but again that is common with most cars.

 

is it likely that the battery is now bad? I have replaced the alternator with a remanufactured one and I can jump start the car but it dies about 5 minutes later every time.

 

Weather's getting hot again in the US, batteries tend to die about this time of year.

If you're not sure of the condition of your battery, take it in to be load tested (most auto parts stores have the stuff to do it), or just replace it - having been stranded with a battery that up & died on me, it sucks. Well worth the $40 or $50 to replace it if it's old.

As for the electrical problems, I'm having those gremlins in my car too, but then the engine died, so I'm sort of unable to troubleshoot. I'd clean up the grounds though, just as a good general idea.

Also, watch out. If your electrical system is acting up, your fuel pump will be acting up. It's a possibility that my engine blew partly because of low fuel pressure under acceleration (though it was pretty disgusting inside anyway).

-=Russ=-

 

what i read about batteries only mentioned cold affecting them. you know of any info about heat affecting them?

 

Yes, it is common knowledge that any temp extreme such as heat kills batteries. Just like if you leave an AA battery in the sun for a week, and it dies. It is the heat that also shortens battery life when you remove the battery tray cover on our cars, but still keep the battery under hood.

And cold doesn't really kill a battery. Cold reduces the battery's reaction, lowering the ability of the battery to store and deliver a charge. It’s trying to start a car with an extra cold battery that kills a battery from cold.

 

You probably discharged the battery enough to effectively kill it when your problems started- all it takes is one bad cell that doesn't want to accept a charge after it's been drained, and the whole battery's kaput...Spend $35-40 & get a new one. If your new alt is now good (pushing over 14 volts), you won't have to worry about the charging system again for a while with a new battery...Clean the wiring up (terminal ends, grounds,etc...) while you're there....

 

You should be able to run your car without a battery. The alternator puts out enough power to make everything run. If I wanted I could take out my battery, get a jump start from someone, disconnect it and go drive around. Its basically needed for starting, not to keep the car running.

 

so if the above post is correct then what should I be looking for? I am getting the battery load tested in 20 minutes just to make sure. I have a new alternator and considering the battery is good, where do I start to fix this problem?

 

That's a very costly mistake, NetSeven, running the car on only the alt- if your voltage regulator decides out of the blue to fritz out and shove 20+ volts through the system without the battery there to absorb and buffer it, you've just waxed every computer in your car...

PureSephiroth- get back to us when you know the batt is good or bad, we'll go from there...

 

autozone said that the battery is fine...

but when the car was shutting down the battery was very very low. I only recently charged it and didn't want to let the car idle to see if the battery would run out again. That battery is now fully charged and "good" as they put it. Where do I go from here?

 

 

I read that. I still don't know where to look...

 

All right, man, put everything back together & get the car started. Grab a meter, set it to the 15v scale if it has one, put the positive lead on the red positive battery terminal, and the neg lead on the neg terminal. Simple enough, eh? What voltage reading do you have?

 

i'll have to do that after work tomorrow. Its dark here in Michigan and I don't have a garage...

 

it blew the fuse on my multimeter...

 

okay, the volt meter is reading about 14.5 with the car on. What does this mean though?

 

Hmm 14.5 says the alternator is live.
Parts store says battery is good.
All that leaves is connections.

You must have bright shinny metal to metal contact.
The battery ground clamp can look good on the outside and be corroded on the inside.

To test- with the engine running & the headlights on:
Measure the voltage drop from the alternator frame to the battery (-).
A good primary ground will show zero volts.

Then measure the voltage drop from the alternator output post to the battery (+).
That should also show zero.

 

what does it read when the engine is warm and the headlights are on (and of course the engine is running)???

Should be at least 13.6 volts...if it is not...welll then again you have a: