mqt_hockey6

iTrader: (2)

Well I had my fuel system redone and afterwords, the car wouldnt idle due to low voltage. I changed the oddyssy pc680 out for a braille carbon racing battery. Everything was fine. 2 days later the car was back firing and died do to low voltage again. I changed out the alternator today and everything cranked up fine. Drove home and on the way home the car started bucking like crazy and back firing going into my neighborhood. finally died on my street and coasted to my house. Anyone have an idea as to what the issue is? I am still breaking in a new motor and it hasnt been tuned yet. Major Mods are a streetport, microtech lt-10s, single t67, fuel system with 4 - 1680cc injectors.

Why do I keep losing voltage. Shouldnt it still run on just the alternator (even though it is bad to run on just the alternator)?

JHew84

iTrader: (9)

When having battery/alternator problems it is not a bad idea to replace both at the same time. A failing alternator will kill a battery, and in turn a failing battery will kill an alternator. Might not be a bad idea to take each in and get them tested, even though I doubt they would go bad that fast.

Also might want to check the coils, if it's sputtering you might not be getting spark. Basically just check over the basics, air, fuel, spark...

- James

rynberg

When you say four 1680cc injectors, are you saying you are using those as primaries as well? Why in god's name would you run 1680cc primaries? There's no way that thing is ever going to have any kind of stable idle.

mqt_hockey6

iTrader: (2)

the idle has always been fine until i have been having voltage issues. the problem here lies somewhere in the electrical system. Voltage has been low and it seems like the alternator isnt always sending power back to the battery. When the voltage gets low its like the coils aren't getting power and it misfires.

mqt_hockey6

iTrader: (2)

also, i am not running half of the electrical stuff in the car. as a matter of fact, most of the harness isnt even hooked up i don't think.

mqt_hockey6

iTrader: (2)

bump for help

JHew84

iTrader: (9)

did you go have your battery/alt tested? look into the coils/spark? we can't help if your not going to help eliminate potential problems...

DMoneyRX-7

iTrader: (2)

have u added grounds or upgrade the grounding system.

oorx7

iTrader: (2)

My problem sounds exactly the same. Here is a thread I posted up. https://www.rx7club.com/3rd-generation-specific-1993-2002-16/need-help-burnt-up-3-odessey-pc680s-576625/

I am going to be trouble shooting this over the next week or so. I have a full size optima yellow that I am using as well as relocating it to the hatch area.

One thing I heard from a old hot rodder is that some times the solenoid on the starter can keep drawing power from the system even though it's not engaging. I have another starter here to try as well.

Anyway give my thread a read, and good luck. I will be watching this thread and if I fix my problem I will post here as well.

mqt_hockey6

iTrader: (2)

im going to test the battery and alternator right now.

mqt_hockey6

iTrader: (2)

alternator checked out fine but the battery needs to be charged before tested.

mqt_hockey6

iTrader: (2)

well i think i may know what the problem is. I didnt replace the battery and alternator at the same time. the pc680 died and i got a braille carbon. then replaced the alternator but at that time the battery was already done. autozone tested the alt as perfect but the battery is bad after 2 days. i will see if that is all on monday when i get a new battery.

JHew84

iTrader: (9)

Yea, that might fix it (hopefully). The one thing I learned over the years is start with the easy/obvious stuff, even if it seems stupid. Getting the battery/alternator tested is easy and has solved many a problem for me over the years haha. Hopefully the battery you bought came with some kind of warranty so you don't have to buy another one.

- James

AnthonyNYC

iTrader: (3)

I have 4 1680 cc injectors and idles perfect at 900 rpms on a TEC3. I've also seen these idle absolutely perfectly with a haltech e6K and 900, rock solid.

Anthony

AnthonyNYC

iTrader: (3)

Let me know how this works out.

Anthony