Woke the car up last Friday, had a maintainer on it all Winter. Started and drove fine.

Went to use it today, battery dead. Hood wasn't completely latched, assume the underhood lights were on and pulled the battery down. No dash, no warning audio.

Jumped it, started right up but idle was wonky. Let it run while giving it a bit of throttle and let it warm up. Voltmeter indicated battery charging.

Started to drive off, clutch in and idling at the end of the driveway waiting for traffic and the idle slowly dropped until it quit and no restart. Popped the hood, no underhood lights. Wiggled the battery connections in preparation for putting the jump pack back on it, lights came on, car started.

Started to drive off but was not confident that things were fixed and didn't want to get stranded so got up to about 40MPH and pushed the clutch in. Sure enough, idle slowly dropped until it quit. Several instances of this after even after running it fairly hard both the get the engine warmed up and charge the battery.

Looked over the wiring for mouse damage, none found. Also checked air filter and intake for mouse house, all clean.

Parked it and have it on a battery charger but not at all sure a low battery is the only problem. Would low voltage affect the ECU in such a way as to cause these symptoms?

 

I would test the battery, make sure it's about 12.6 volts......Start the car ( if it will start ) and test battery, should jump up to about 14.5 volts.........I would also clean the battery connection with a wire brush, same goes for the cables. Then apply some electrical grease and retest....

 

Pulled the cables off, no corrosion but not shiny-bright either. Wirebrushed, dabbed some dielectric on the surfaces and threads, reinstalled.

Did notice the positive cable had a separate piece between the cable and the battery terminal which I don't recall ever seeing. (Side-terminal battery - not my favorite kind...)

Reinstalled and snugged everything down. Load tested battery, no significant drop. Started the car on the partially charged battery and it's charging at 14.5x volts. Did notice that the idle stayed consistent so it may have been a combination of low battery voltage and iffy connection.

I'll leave it on trickle charge overnight and report back tomorrow.

 

For the umpteenth time, dielectric grease is an INSULATOR, does NOT give you a good electrical connection. Use NO-OX-ID, a conductive grease, to give a good electrical connection.

 

All better now. Cleaned/tightened as mentioned above, smart charger said it was 100% by the time I got up from my nap, started and idled fine while I geared up for a trip to town.

25 miles each way, no issues at all. Not letting the battery get fully charged initially was most likely the main culprit, but resetting the ECU while cleaning the terminals might have contributed.

Thanks for all the input.

 

I have tube of that, but for the life of me, I couldn't remember specifically why I bought it. Now I remember. Thanks!

Should probably clean up the bulkhead and hit that, too, while I'm there.