2000 LS... RF P3001 Amp Shutting Down Car?

[djthechemist]

Hey there, new to the forums but having exteme difficutly with this car
its a 2000 Lincoln LS, with base system (not alpine)

When installing this amp for the customer after about a week his car keeps shutting down. when he took it to his mechanic he said that it was the way the amp was wired, which i know is correct... Positive to battery (fused) and a short ground to the chassis of the car. The remote turn on is comming from Accessory wire in the ignition. Any help or known problems with this?

i mean that amp draws no more then 40 amps at high level, theres no way this should be shutting down his car?

he even changed his 110 alternator to a 130 aftermarket and still the same problem.

the customer tells me that his mechanic also said it was his battery detecting an amp draw to high and shutting down the car so the battery does not die? does this sound correct?

thanks in advance

-DJ The Chemist

[shorod]

The electrical systems in the LS is very sensitive, so it could be the case. A quick way to verify the mechanic's claim would be to pull the fuse for the amp and see if that fixes the stalling problem. If that fixes the stalling, the next option would be to install a stiffening capacitor on the amp power lead? With a 40-amp draw, that must be around a 400 W amp. You should be able to get by with a 0.5 Farad capacitor. Anything larger would be overkill, but wouldn't be detrimental (except to the pocketbook).

-Rod

[djthechemist]

Do you mean pull the inline fuse from the battery?
we have not done that yet, but we did add a 1.0 Farad Cap.
the cap didn't solve anything so i guess we will see if pulling the fuse does anything?

altho i don't think it makes too much of a difference because we unhooked the B+ terminal to the amp and that solved the problem
its just not making sence to us...

[shorod]

Oh, you didn't mention in your original post that you pulled the power wire for the amp and it solved the issue. Yep, that is where I was going with the suggestion to pull the fuse for the amp. A battery has too high of an internal resistance to respond quickly to current surges, same goes for the alternator. The cap should help out with that. I'm surprised it doesn't.

Do you have access to a current meter to monitor the draw on the system when the amp is connected, powered up, and pumping out bass? Does the car only stall when the volume is up and the music has a lot of bass?

-Rod

[djthechemist]

The car still stalls @ a low volume. It doesn't make any sense...

when we brought it into our shop to test it, the car never physically did it for me. he said that it only does it when its warm out side...
makes noo sence to me whats so ever... its currently 8 degrees C out?

Also.... he said that it stalls at a red light at idle.. thats the only time.
he also said that when he catches it stalling... everything shuts down, lights engine, radio, gauge cluster
but the battery warning light comes on, and 3 seconds later the check engine light comes on

[shorod]

Have you tried checking the various computers for diagnostic codes?

How old is the battery? There have been a lot of stalling and other electrical issues with these cars due to old batteries, even if they weren't 5 or more years old.

Also, is this the V6 or V8? The stalling description by itself resembles what might happen if the PCV elbow is getting soft. That is only a factor on the V6 though. Since the stalling is intermittant, maybe the amp wasn't left disconnected lone enough to determine if the stalling really did stop when the amp was disconnected.

-Rod

[djthechemist]

There was no codes...
but i personally think it is his IAC Motor...
His mechanic said that would have thrown a code if that was the case
but in my opinion hes just a code reader and belives that all problems will throw a code...not a true mechanic

when i physically measred the resistance on the IAC, it was 1.5 Ohms
and it should be 6-12 for the soloniod to be in working condition...
oh well! not im my place to tell him without puttin a new one in and trying that out

it is the V8 model, but irregadless we are taking the entire system out
im fed up and hes just not a plesent guy to deal with

Thanks for your help mate, really appreciate it!

[shorod]

For what it's worth, my wife's LS would sometimes stumble and the engine speed would blip when the A/C turned on. Her car had no codes, but I replaced the IAC anyway and it solved the issue. I had previously cleaned it and the passages with no change. They can become slow to respond.

Yep, sometimes it's better to cut your losses and move on.

-Rod