Intermittent no crank , battery flickers with bass hit, parasitic draw

[88sogreatv8]

I have an issue with my battery draining down to 5 volts after sitting in my garage for a month. The other issues i think are related is sometimes the vehicle will not crank . I have to work the ignition several times to get it to crank. I also noticed that when my bass hits my lights dim . I think it is related to a ground issue. I have done a continuity test and i have good chassis ground. The battery is new, the starter is new and i have a high amp alternator. I am thinking of redoing the ground to the engine block. It is original to the engine i got from the junkyard. this 1uz is also swapped into a 1988 cressida

 

[P Bateman]

To chase down parasitic current draw:
- switch the ignition off and remove the key
- disconnect your negative battery terminal
- Set your multi meter to AMPS and place it between the negative battery terminal and the cable

An acceptable level of parasitic current draw is around 20 to 50 mA

If the current draw is higher, start pulling fuses out one by one, each time checking the current draw, the refitting the fuse
When find the fuse that makes reading drop into an acceptable range, you know which circuit is sucking the battery dry.
From there, you'll need to diagnose the circuit.

Deal with this first before you start chasing ignition switch and audio system issues.

BTW continuity tests are NG. A thick-ass battery cable that is cut through to one remaining strand still has continuity but is clearly unfit for purpose. Resistance tests are always the best way to go. Make sure your battery cables have a clean unpainted bare metal surface to bolt onto.

PB

 

[88sogreatv8]

Update . Pulled the starter and bench tested it. Seems to be working fine. Did a draw test. showed no draw at all . My main concern is the original main starter wire and the ground wire. they both came with the used engine. Im going to replace both wires and cross my fingers. I am also replacing the starter to be safe. Update soon..

 

[ivan129]

This looks to be the same, or similar problem you raised 2 and half years ago.
Forum Members advised you to replace the power and ground leads back then.
Maybe its time to get an auto elec to take a look at it.

 

[88sogreatv8]

This looks to be the same, or similar problem you raised 2 and half years ago.
Forum Members advised you to replace the power and ground leads back then.
Maybe its time to get an auto elec to take a look at it.

Thank you for the response .
I just replaced all the ground cables and power cables. I added an additional ground directly to the starter housing.
Unfortunately still have this issue. is the possibility that an aftermarket alarm could cause such an issue?

It honestly seems like the starter isn't receiving enough voltage it needs to crank

 

[ivan129]

I guess its possible that your aftermarket alarm could be the problem.
Why not isolate it, to see if that makes any difference.

Your statrter gets its ground (Battery -ve) through the starter body to the engine block via the ground cable back to the -ve termial off the battery.
There is no need for a seperate ground to the starter.

The starter solenoid has a heavy power feed from the +ve battery. You should have full battery voltage there. This provides the grunt to the starter so it can crank the engine over.
A smaller wire from the ignition key applies battery voltage to the solenoid that causes the starter to engage with the ring gear on the flywheel to crank the engine over. Its possible that your alarm maybe wired into this starter solenoid wire affecting the delivery of power to the solenoid.
Most alarms that I have seen can use a relay to switch this wire.
You can also get high current relays (like 200A) that can be used to switch battery power on and off. I use a remote one on my car in addition to the alarm that isolates the starter feed.
Try to record the sound of your intermittent start makes and post it on the forum. It might help.