91 SS sedan electrical problem stalling / loss of power

[turbo4life]

hi guys, i recently purchased a 1991 legacy SS with 235k miles. it has some wired electrical issues.

here are a few pictures of what it looks like on the outside. i love this car!!











on the dash the battery, and brake light flash but get brighter and stay on almost as i step on the gas then the car accelerates but not making much power and then it will jerk (like it shuts off for a split second) and back fires with a loud bang usually.


things i have done so far

1. i added a ground strap form engine to body since the one on the transmission is missing (that seem to fix one problem the fuel gauge used to have a mind of its own and just go everywhere now it is accurate)

2. today i loosed the 4 grounds in the engine compartment and moved them around and re tightened them

took it for a test drive and it runs bad no power back fires and dies for a split second.

the other thin is it ran great for one day after adding that ground and now today its acting up so im not sure what is going on.

heres a picture of the gauge cluster



any help will be greatly appreciated!!

[Legacy777]

You've probably got an issue with the alternator. I'd suggest bringing in the alternator to have it tested.

[turbo4life]

so your saying alternator can can cause loss of power? well ill just install the alternator from my other legacy. but the thing is i drove the car and it did not give me a single problem yesterday it had full power and everything. this problem just comes and goes its odd.

[oldscoobyturbo]

first swap the alternator.
next check the ground for the fuel pump or just add a new wire from the ground in the plug to the bolts holding the unit on the tank.
how's the knock sensor look?

[turbo4life]

the knock sensor looks ok. it dose not show a crack or anything. like i said with the battery and brake light coming one and flashing or staying on sounds to me like electrical issue whit a ground somewhere. if someone had a nice wiring diagram or ground points in the legacy would be great.

also i have a wide band in the car and that also resets when the thing is acting up like the ecu or something is loosing power...

[cj91legss]

Seems like a loose ground somewhere.

But like the others stated, usually when your battery and brake light come on it means the alternator is toast.

[turbo4life]

i haven't changed the alternator but the car currently runs great it fixed itself weird again.. but thanx for the input guys! ill just do the alt when it goes bad again.. thanks again!