03 WRX WAGON ELECTRICAL PROBLEMS

[DRDANC805]

hello there any help is appreciated...the problem i am haveing is really tripin me out , the car is an 03 wrx wagon. here is the problems when i start the car in the morning sometimes it wont start once its started usually by jumping it it starts up but the car has no power at all i think its either the battery or a bad alternator, my question is this would a alternator thats going out cause the car to loose power and cut in and out of boost?
i have tested the battery and it reads 12 v. The alternator was tested while the car is running with a volt meter and its putting out no more than 12.5 volts ant any rpm.

if i need to replace the alternator what should i ask for i have heard that a 2005 wrx sti alternator is a direct replacement and it puts out a little more amperage than the stock unit, if someone can conform what year sti alternator fits that would awesome

thank you in advance DANC

[oguitar]

Welcome to the site.

How old is the battery in your car? This would be my first guess. I haven't really seen too many reports of alternators going out on people. Also is this a used vehicle? If it is, has someone been playing with the electrical system? Like an aftermarket radio or something like that.

[DRDANC805]

WELL I REPLACED THE BATTERY AND THE ALTERNATOR,,, WHILE THE ENGINE IS IDLEING ITS AROUD 12 VOLTS AND ITS 12.9 FRON THE ALTERNATOR,, I THOUGHT THIS WAS GOING TO CURE MY PROBLEMS BUT IT DIDENT... THE CAR STILL IS ACTING UP IM SURE ITS GOT GREMLINS IN THE ENGINE,SOMETIMES WHEN I DRIVE THE CAR IT FEELS LIKE THERE IS NO POWER THEN IT OTHER TIME IT SCREAMS AND RUNS FINE NO STUTTERING WHILE IN BOOST. IM AT A LOSS AS IT RUNS LIKE THIS WHILE RUNNING RACE GAS 100 OCTANE SO I DOUBT ITS KNOCK BUT I COULD BE WRONG . I JUST NEED TO KNOW WHERE AND WHAT COULD BE CAUSEING THIS!!!

[oguitar]

First of all don't buy any more parts until you are sure it is the issue.

You need to approach this problem methodically. Write the problem down on a piece of paper. Accurately describe the problem and any mods done to the car.

If you don't want to do this look for a bad ground or short somewhere. Only you or a mechanic are going to fix this problem. Good luck.

[Anub1s]

Check both terminals at the battery, make sure they are clean and that the wires are well seated and clean. Then check connection between the battery and the starter, it may have come loose.

You will also want to check your major grounding points in the engine bay, starting with the battery.

[DRDANC805]

ok will do.. yesterday while driveing home from work its ran perfect for a while then it ran like **** cutting in and out of boost and ****ty idle while stoped

i have noticed when i turn on the headlights it makes the car run ****ty also causeing it to sputter in and out of boost also the cel came on and gave me a cel i ran a scanner and its
p0301 and p0303 wich is misfire. i think there is a combination of things going on but i cant figure this out..

[DRDANC805]

update

drove the car to work today and its still runnis like **** sputtering and cutting in and out of boost . once lunch came aroud i went to start the car and it wouldent start just made a single click . i tested the battery voltage and its 12.5 volts , jumped it with a friends car and it started but idle was a little rough and i had a cel this time im getting p0463 and p0335. this is really causeing me to stress out any help is appreciated


danc

[oguitar]

Try running the car without the MAF sensor.

This might help as well.

http://www.eetimes.com/electronics-b...ngine-problems

Electrical problems can be terribly tough to troubleshoot. You still have not answered my question if someone has been playing with the electrical system on your car.

[DRDANC805]

ok heres another update on my way to work today the car just turned of and would not start up, no power at all i just had it towed to a friends and am chargeing the battery now,


as for the electrical system no ones been messin with it as far as i know

its sitting here and im chargeing the battery now ...........

[2ndSuby]

really poor ground ... with all you have stated ... sounds like no ground...

[Anub1s]

Did you check your terminals and your ground connections?

[DRDANC805]

UPDATE

AS PER YOUR ADVICE I CHECKED THE GROUNDS AND FOUNT THAT ALL OF THE GROUNDS WERE FUCT ON THIS CAR... THE ONE ON THE BACK OR THE MOTOR UNDER THE INTERCOOLER WAS CORRODED GREEN AND WHEN I TOUCHED IT IT JUST CRUMBLED THE ONTHER NEXT TO THE BATTERY WAS PUT BACK ON AFTER THE ENGINE BAY WAS PAINTED SO THERE WAS REALLY ****TY CONTACT


I WOULD LIKE TO SAY THANKS FOR YOUR HELP IN GUIDEING ME INTO THE RIGHT DIRECTION AND GETTING MY PROBLEM TAKEN CARE OF.....

THANK YOU