2005. Just took my car to the shop for the 2nd time in a month.
Suddenly my car wouldn't start after being off for 30 minutes. Saw that oil was almost empty and leaking. Radiator fluid low too. I put more fluid in both. No start.
Mechanic said fuel pump is bad.
Opted for leak repair fluid on the oil leak (I'm poor, not enough money to take engine out and replace the mains), put some fluids in her, replaced the fuel pump.
Car starts, but now the battery light goes on and off intermittently (3 seconds on, 10 seconds off, 15 seconds on, 7 seconds off, etc).
Battery died on me while driving after about 4 hours of driving or so. Got a new battery, just to be on the safe side.

Battery light issue persists. With new, fully charged battery, over the course of an hour or so of driving, battery drains a little. Doesn't drain when engine is off.
I wanted to test battery levels and alternator. Get out multimeter. Cold battery was at 12.2 or so.
I turn the engine on, I watch the battery drop from 12.2 to 11.4 over the course of 20 seconds. No idea why.

1) Is there any way in heck that putting multimeter on the terminals could cause a battery to drain faster? Or maybe it just drains faster when the car isn't accelerating (alternator is putting out less charge)?

2) Could the low oil have damaged both the fuel pump and the alternator?

3) If the new fuel pump wasn't wired up properly, could it be causing battery drain when the engine is running?

4) What other questions do I need to be asking?

Thanks

 

Whoa, this has to break the record for the most amount of moving parts in a starter thread. Welcome to the forum, lets see if we can help.

The battery symbol light in the dash means that the alternator output voltage is lower than the battery voltage. Its a "no charge" light if you will. This can be the battery, alternator or wiring. When the truck is running, what is the voltage at the output stud of the alternator?

Check all wiring and connections at the battery and alternator to make sure they are clean and tight with no frayed or corroded wires or connectors.

A fully charged battery holds 12.6V after you knock off the surface charge with the headlights for 2 min (then wait 15 min to test). Can the battery do this after a full charge cycle?

Your multimeter in voltage mode cannot drain the battery. The battery voltage drops when you put the ignition in the run position or when you start the truck and its running or both?

Yes a battery can be drained by any number of faulty circuits that don't fully turn off when the truck is turned off, you would need to do a parasitic load test which measure the residual current drain on the battery of a fully shut down truck. this may or may not be happening but you have a charging problem that needs to be resolved.

Low oil can cause a lot of problems but not a dead fuel pump or alternator.


George

 

Thanks, George. I'm a car owner for two years now and haven't had as much opportunity as I'd like to learn about engine operation and maintenance.

I'm not able to get the battery fully charged right now, but I put a multimeter on it and got 10.2 Volts.
I used a jump-start charger to get the car running, voltage quickly dropped down to 8.8 or so and then seemed to stabilize there (car continued to run).

I read the output on the alternator. Started around 10.3, slowly dropped down to 8V over the course of a few minutes. It might have kept slowly dropping but I turned the car off.

Doing a quick battery reading to see if there's any parasitic drain when the battery is off:
@4:35pm -- ON position: 9.55; Accessories position: 9.64 OFF: 9.97
Will check again in a few hours.

"A fully charged battery holds 12.6V after you knock off the surface charge with the headlights for 2 min (then wait 15 min to test). Can the battery do this after a full charge cycle?"

Are you asking if the battery can hold it's full charge (12.6v)?
I'll be able to charge it up fully tomorrow or Monday and run further tests/readings.

 

Yes first you need a good battery which can charge to 12.6V and then it has to maintain a minimum voltage under a high load. Then you need proper alternator output.


George

 

The battery is brand new, so shouldn't be the issue, but I'll check.

If alternator output is low (as with mine), is first step to just buy and install a new one, or are there other things to check which might be causing the low output?

 

There can be issues besides a faulty alternator like a slipping belt or a fault in the lamp circuit that does not allow the alternator to turn on. Some parts stores can test it for you after to take it off to verify, which is pretty painless confirmation. That said the alternator is likely to be bad.


George