Alternator/Electrical Problem

[marcman804]

The other day I noticed that the battery and the brake light was on and at the time I didnt know what it meant but as soon as I got home I checked on here and it meant that the alternator was about to die. Well my car ran fine and the next day I had an interview for a job that was an hour away so I figured it should make it because I didnt receive any signs that the alternator was completely bad, the lights didnt dim or anything and when the bass hit in my car they didnt dim. (BIG MISTAKE) Well after the interview I went over to my friend's house not too far from where the interview was and when I turned on my high beams they both blew out. When I got to his house I called my dad and he said the regulator on the alternator must have went out. I checked the voltage reading on my turbo timer read 17-19 volts.WTF Well I decided to drive the car home anyhow but I didnt make it. I heard a loud pop and then the windshield wipers went crazy and then the car slowed up and came back and then another pop. Luckily a guy that lives nearby me was behind me and pulled over alongside me. When I popped the hood I could smell the battery acid. Well I got the car home and bought a new battery and the car starts fine but when you turn the key off there is a loud buzzing coming from the radio, and when the key is on the fans run constantly and I believe the fuel pump runs constantly. What could this be???? thanks a lot sorry its so long but I wanted to include all the details.

 

[luv2rallye]

17-19V is way too high. Your alt is overcharging and cooking the battery - bad alt (it's regulator). 14.4V is normal and anything over 16 is too high. Fix this first.

 

[marcman804]

thanks a lot. Im going to replace the alternator tomorrow. I was still wondering what could be causing the buzzing noise when the key is off? I searched and ive seen it may be the ECU but I thought if the ECU is bad the car maybe wouldnt run at all?

 

[asexton6969]

Yea you were applying too much voltage, don't be surpised if you burned out solenoids, fuses, accessories.

 

[marcman804]

Is there an easy way to find out what solenoids and relays may be blown out?

 

[marcman804]

ok so i replaced the alternator and the battery. i checked the voltage and its steady at around 14 volts. whenever i turn the key off there is a buzzing noise from inside. it doesnt do it when the key is on but whenever i turn the key to the off position it starts. i traced where the buzzing was coming from and its coming from a relay on the passenger side beside the stereo. Its two relays connected together on a bracket. One is buzzing and one is not. I replaced both of them but the buzzing didnt stop. And for some reason both of the fans stay running, the cooling fan and the ac fan. here is a picture of the relays and where they are located, the number on the relays are E8T101 6520 i was wondering if anyone could tell me what I could do to fix this.

 

[marcman804]

and another thing.... my car runs but it runs really bad, I was afraid to drive it hard so I was easy on. It idles very badly as well.

 

[XilArAtiNG]

seems like you may have some electrical damage done to the ECU because I believe those are fuel pump and MFI relays

http://www.dsmtuners.com/forums/newbie-forum/276071-mfi-fuel-pump-relay.html

heres a link to a thread concerning the relay, hope it helps

 

[marcman804]

Thanks a lot. I believe that's the problem as well. So should I just buy an EPROM so I can tune my car?

 

[DSMopar]

Jeez like DSM ECU's aren't fragile enough, what the hell did you think would happen if you kept driving around at 17-19 volts?

 

[John Samuels]

Hi! DSMopar,

I'm a 1G (91 TSI 2L T AWD) newbie from Ontario.

I am having a problem with my alternator.

Replaced it (Reman) 2 months ago, and new alt was putting out 14.5V consistently.

Yesterday I ran into an alt problem.

When I start up cold (to 1,250RPM) everything OK, 14.5V, bright lights etc.

After warm up and revs dropped to idle @ 850RPM, nothing from the alt, battery showing 11.5V, and when cooling fan came on, volts continued to fall.

Let it cool down, restarted engine (to 1,250RPM), great alt volts, bright lights again, until idle, same problem.

I have studied all the archived threads and primers.

I am changing the alt relay (or charge light relay as it is called) Monday.

Any additional suggestions?

Would greatly appreciate your input.

Regards,

Respectful Grasshopper

 

[marcman804]

Well I finally had a chance to remove my ecu and everything looks fine no leaks or anything unusual. What could be the problem? The car starts but idles terribly and when I turn the key to the on position I can hear the fuel pump run constantly.

 

[95GSXBLUR]

I would strongly suggest a quality alternator like one from ALTERSTART (ALTERSTART Home Page) or an OEM replacement. I've gone through between 3-5 remans from various auto stores - they're all junk made with really cheap parts that fail.

yes the new one will be more expensive, however, it will solve all your charging issues.

I also suggest getting a Jays alternator relocation - heat is the #1 enemy of the alternator.

 

[DSMopar]

Well I finally had a chance to remove my ecu and everything looks fine no leaks or anything unusual. What could be the problem? The car starts but idles terribly and when I turn the key to the on position I can hear the fuel pump run constantly.

Just because it 'looks' fine doesn't mean shit, many components can still be fried to hell. If you're fuel pump is on constantly that's a good sign you ####ed your ECU. God help you with whatever else you might have ####ed up, various sensors, wiring etc

 

[DSMopar]

Hi! DSMopar,

I'm a 1G (91 TSI 2L T AWD) newbie from Ontario.

I am having a problem with my alternator.

Replaced it (Reman) 2 months ago, and new alt was putting out 14.5V consistently.

Yesterday I ran into an alt problem.

When I start up cold (to 1,250RPM) everything OK, 14.5V, bright lights etc.

After warm up and revs dropped to idle @ 850RPM, nothing from the alt, battery showing 11.5V, and when cooling fan came on, volts continued to fall.

Let it cool down, restarted engine (to 1,250RPM), great alt volts, bright lights again, until idle, same problem.

I have studied all the archived threads and primers.

I am changing the alt relay (or charge light relay as it is called) Monday.

Any additional suggestions?

Would greatly appreciate your input.

Regards,

Respectful Grasshopper

You're not real clear on what's going on, are you saying it only stops charging at idle once warm, or does it stop charging completely?

 

[John Samuels]

It stops charging once warm, then no charge at idle or with revs.

I switch off, cool down for 2 or 3 minutes, then restart (dash alt light goes out and stays out) and it charges great until warm again, then for no reason no charge.

At start up battery test @ 14.5V, once warm, battery test 12 down to 11.5V.

Charging system tester shows green light (good charging) at start up, once warm yellow light (good battery), after 2-3 minutes running at idle tester shows yellow and red lights, fading to red (poor battery).

Something happens at warmed up idle.

I have checked all grounds, etc.

I have a relay on order.

 

[DSMopar]

Ya check the simple stuff first, but in all likeliness I'd bet on the reman alt being bad... they really are terrible. I have one in my car and it's barely hanging on, doesn't charge for shit at idle (have to rev to 1200+). It's only a year old...

 

[John Samuels]

Thanks, DSMopar, I am swapping it under warranty.

 

[marcman804]

ok so im going to get an eprom ecu but the guy im getting it from already had it socketed, i was wondering if this will be a problem being that im pretty much going to be running the stock set up on my car until i get the extra money to get an fpr and a walbro fuel pump. i have 680cc injectors that i will be installing once i get the fuel pump and the fpr. will my car run right with the 450s until then on the eprom ecu?

 

[John Samuels]

DSMopar, Thanks!

Swapped my Alt under warranty (which they insisted tested OK) and she purrs like a kitten again. No surge or dim lights now, also battery holds consistant charge.

My old alt was only 2 months old.

John Samuels

 

[marcman804]

ok i finally got a socketed eprom ecu. i bought the stage 3 keydiver chip installed in it. i bought an aeromotive fpr, walbro 255 and the new relays that go on the passenger side. i installed everything but for some reason there is no power coming the fuel pump. I even tried the stock fuel pump but still no power is coming to it. what could this possibly be, im getting so frustrated with this i could pull my hair out.