1.8T Alternator? Flashing light...???

**Joesturbo** · 12-20-2008 07:08 AM

So I had some coil pack issues, battery issues and now I am thinking the culprate was the alternator...

The symptom is this.. Normal acceleration/dirving is ok no problems at all - however once you step on the throttle a little more the battery indicator/icon on the cluster flashes... Let off the throttle and it goes away.

I am guessing it is toast? Or can I change out the brushes? Or is it re-build time?

Did a search, but did not find anything that really answered the question...

Thanks,
Joe

**Joesturbo** · 12-20-2008 09:38 AM

bump...

**illaudiill** · 12-20-2008 10:45 AM

Originally Posted by Joesturbo

So I had some coil pack issues, battery issues and now I am thinking the culprate was the alternator...

The symptom is this.. Normal acceleration/dirving is ok no problems at all - however once you step on the throttle a little more the battery indicator/icon on the cluster flashes... Let off the throttle and it goes away.

I am guessing it is toast? Or can I change out the brushes? Or is it re-build time?

Did a search, but did not find anything that really answered the question...

Thanks,
Joe

Go get it diagnosed. could be fuel pump or Alt

**Joesturbo** · 12-20-2008 11:20 AM

Ok,
hooked up my VAG-Com and did a Scope and Log file...

Voltage at the battery no load and not started 12.6 - on average after this - voltage between 13.3 - 13.5/13.6 - Note this was with AC and headlights on.

I did not capture the marker when the voltage light flashed and when the check engine light came on directly after... both went away and I tried to reproduce the problem but never could.

Here is the log info...
Saturday,20,December,2008,13:03:49
8E0 909 518 AK ,,1.8L R4/5VT G 0003,

,Group A:,'004,,,,Group B:, Not Running,,,,Group C:, Not Running
,,RPM,Voltage,Temperature,Temperature,,,,,,,,,,
,TIME,,,,,TIME,,,,,TIME,,,,
MARKER,STAMP, /min, V,°C,°C,STAMP,,,,,STAMP,,,,
,0.01,1400,13.580,82.0,60.0,,,,,,,,,,
,0.18,1400,13.510,82.0,60.0,,,,,,,,,,
,0.36,1400,13.510,82.0,60.0,,,,,,,,,,
,0.54,1400,13.510,82.0,60.0,,,,,,,,,,
,0.72,1400,13.510,82.0,60.0,,,,,,,,,,
,0.90,1400,13.510,82.0,60.0,,,,,,,,,,
,1.08,1400,13.510,82.0,60.0,,,,,,,,,,
,1.25,1400,13.440,82.0,60.0,,,,,,,,,,
,1.42,1400,13.580,82.0,60.0,,,,,,,,,,
,1.59,1400,13.580,82.0,60.0,,,,,,,,,,
,1.76,1400,13.580,82.0,60.0,,,,,,,,,,
,1.93,1400,13.510,82.0,60.0,,,,,,,,,,
,2.10,1400,13.510,82.0,60.0,,,,,,,,,,
,2.27,1400,13.510,82.0,60.0,,,,,,,,,,
,2.44,1400,13.580,82.0,60.0,,,,,,,,,,
,2.61,1400,13.440,82.0,60.0,,,,,,,,,,
,2.78,1400,13.510,82.0,60.0,,,,,,,,,,
,2.95,1400,13.510,82.0,60.0,,,,,,,,,,
,3.12,1400,13.510,82.0,60.0,,,,,,,,,,
,3.29,1400,13.510,82.0,60.0,,,,,,,,,,
,3.46,1400,13.510,82.0,60.0,,,,,,,,,,
,3.63,1400,13.510,82.0,60.0,,,,,,,,,,
,3.80,1400,13.580,82.0,60.0,,,,,,,,,,
,3.97,1400,13.440,82.0,60.0,,,,,,,,,,
,4.14,1400,13.510,82.0,60.0,,,,,,,,,,
,4.31,1400,13.580,82.0,60.0,,,,,,,,,,
,4.48,1400,13.580,82.0,60.0,,,,,,,,,,

Here is a screen shot of the scope: Note: RED=RPM Green=Voltage

I am wondering if it could be the wiring or a bad ground somewhere? Also why do you say the fuel pump?

thanks!

**Joesturbo** · 12-20-2008 03:02 PM

bump

**mtbrider** · 12-20-2008 03:23 PM

before you buy a new alternator, check the ground by the motor mount..if you have to buy one thou I have one that I can sell to you for cheap.

**Joesturbo** · 12-21-2008 08:25 AM

OK where is the connection? is it on the passangerside below the turbo?

Any other ideas?

thanks,
Joe

**Joesturbo** · 12-21-2008 11:17 AM

Just an update: Went out this morning - sunny skys return to NC after a week - So no lights on at all and I cannot re-produce the error code... I am thinking it is a multiple issue here: 1. Battery was bad and caused initial issues. 2. It took some time for the ECU's to adapt to getting proper voltage. 3. I don't know if there are grounding issues - but it sure does seem to point to that- Again anyone know where the main grounding points are? My ekta does not have enough information to help me out here.

**AudiA4_20T** · 12-21-2008 11:58 AM

your voltage looks solid as hell on the graph... I would wait until it comes back

**Joesturbo** · 12-22-2008 10:51 AM

ok -was able to re-create at least the misfire... again all 4 coilpacks have been replaced! This is getting on my nerves!

VAG-COM Version: Release 311.2-N

Control Module Part Number: 8E0 909 518 AK
Component and/or Version: 1.8L R4/5VT G 0003
Software Coding: 0016751
Work Shop Code: WSC 63251
2 Faults Found:
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded
16686 - Cylinder 2 Misfire Detected
P0302 - 001 - Upper Limit Exceeded

**Joesturbo** · 12-22-2008 07:03 PM

Monday evening bump

**Joesturbo** · 12-24-2008 08:44 AM

bump

**Joesturbo** · 12-29-2008 01:49 PM

Ok final update with the resolution incase anyone searches in the future...

After a week - I have scanned the ECU again and everything is working properly again... It appears that I had two spark plugs which were fouled. They were an experiment that I was testing with Pulstar plugs. They worked great for about 6 months, but have faltered and caused major pain. I am guessing with our issues with the coil packs that these are just incompatable.

So I can continue my investigation with a negative for newer cars vs. these things are great for older non-obd2 cars. Either way, they did work very well and gave better MPG for the period that they worked.

Joe