Alternaor fuse problem?

[93_GEE_ES_EX]

First of all I've used the search button and still don't know what it could be.

I recently upgraded my alternator to a 90 gvr-4 alternator.I also relocated my battery to the back.

When im driving normally everything is ok but when I put load into the motor and im around 5k and up my car gets some type of fuelcut FEELING not fuel cut tho and blows the alternator fuse and my warning lights turn on.

Anyone know what can it be?
This is in my 1st gen TSI.

 

[LunarEclips]

is the alternator used or new?

 

[93_GEE_ES_EX]

It was new from the dealer.It's maybe 5 minths old now.

 

[GTM]

First of all I've used the search button and still don't know what it could be.

I recently upgraded my alternator to a 90 gvr-4 alternator.I also relocated my battery to the back.

When im driving normally everything is ok but when I put load into the motor and im around 5k and up my car gets some type of fuelcut FEELING not fuel cut tho and blows the alternator fuse and my warning lights turn on.

Anyone know what can it be?
This is in my 1st gen TSI.

Since I'm not a DSM expert I plead ignorance to what you have installed. Take a look at my "2 minute alternator circuit test" in the Tech Forums under electrical & wiring and see if it's applicable.

It probably will pass those tests without a problem. Unfortunately I'm suspicious of an internal Alternator problem which is heat generated. This is assuming you have done your wiring correctl and are using the correct rated fuse.

Four things come to mind:

The rotor is not running true and hitting the stator (possible bearings).

Heat short in stator windings or caused by vibration.

Intermittant short in diode pack

Regulator loose or malfunction.
..........................

In theory the Alt should be able to achieve max output at 2000 engine RPM unless you have installed an underdrive pulley. You might try to load everything up as I describe in the last part if you have an inductive ammeter.

You could also hook up a decent volt meter to see if it's spiking when it gets near the 5,000 RPM The problem with DVMs is they only sample about every 1/2 second so it could be spiking to 20-48 volts for 1/4 second and you wouldn't see it. An analog meter might be a better choice for you can see that the needle has moved and yet not need to know the exact voltage. This isn't an absolute but you might just catch some errant transient problem in the act.

You may also need to install a shunt volt amp meter at the battery or the battery cable that feeds the sustem under the hood.

Since this seems to be time/temp/heat related it may need a carbon pile load test. I'm sure you can find instructions on how to build one on the internet for it's commonly used in Ham radio gear, you will need to know your starter draw if in series.

You might try pulling it and having it tested at a service if not prepared to DIY.

Cheers,
GTM

 

[93_GEE_ES_EX]

Since I'm not a DSM expert I plead ignorance to what you have installed. Take a look at my "2 minute alternator circuit test" in the Tech Forums under electrical & wiring and see if it's applicable.

It probably will pass those tests without a problem. Unfortunately I'm suspicious of an internal Alternator problem which is heat generated. This is assuming you have done your wiring correctl and are using the correct rated fuse.

Four things come to mind:

The rotor is not running true and hitting the stator (possible bearings).

Heat short in stator windings or caused by vibration.

Intermittant short in diode pack

Regulator loose or malfunction.
..........................

In theory the Alt should be able to achieve max output at 2000 engine RPM unless you have installed an underdrive pulley. You might try to load everything up as I describe in the last part if you have an inductive ammeter.

You could also hook up a decent volt meter to see if it's spiking when it gets near the 5,000 RPM The problem with DVMs is they only sample about every 1/2 second so it could be spiking to 20-48 volts for 1/4 second and you wouldn't see it. An analog meter might be a better choice for you can see that the needle has moved and yet not need to know the exact voltage. This isn't an absolute but you might just catch some errant transient problem in the act.

You may also need to install a shunt volt amp meter at the battery or the battery cable that feeds the sustem under the hood.

Since this seems to be time/temp/heat related it may need a carbon pile load test. I'm sure you can find instructions on how to build one on the internet for it's commonly used in Ham radio gear, you will need to know your starter draw if in series.

You might try pulling it and having it tested at a service if not prepared to DIY.

Cheers,
GTM

I had it tested and it turned out to be fine.But the problem I think is because im still using the 80amp fuse.I might try 100amp fuse and see if it will fix it.

 

[GTM]

...
im still using the 80amp fuse.I might try 100amp fuse and see if it will fix it.

It's the small things that you forget to mention that get you in trouble.

I don't know the rated output of the new Alternator or if you are running an aftermarket amplifier. Looking at some of the '96 schematics I see they used a 120 amp main fuse, you might consider this if you have problems with a 100. Did the rewire/relocate battery instructions give wire size specifications? Hopefully you increased the B+ wire size from the Alt to this fuse by at least 1 gage size. Here in the US they are in even numbers so you are stuck with a 2 gage jump so if it's an 8 you would use a 6 which in theory should double the current capacity.

When selecting wire get the most strands available and silver plated if possible. This is not a normal hand crimp fitting but you have 2 or 3 choices, you can silver solder terminals, you can buy a screw together swage which must be checked on occasion or you can buy a rigging wire cable crimping tool. This can be found at some regular hardware stores or marine hardware stores for around $8-$12. If you plan on doing more large wire crimps this will be most practical. They usually have about 3 hole sizes in each tool and there are 2-3 different bar sizes. You can make your own terminals from copper tubing, a vise, hacksaw, and a drill. Allow enough room for 2 crimps on the tubing.

Let us know if any of this solves the problem.

Cheers,
GTM

 

[93_GEE_ES_EX]

I put in a 100amp fuse and it's working so far.

 

[93_GEE_ES_EX]

Ok the fuse held up good, but the same thing happend.All the warning lights came on and I had to get jump started 3 times until I got home.
What can it be?

 

[93_GEE_ES_EX]

Anyone ?

 

[Lordpaxin]

look along the wires for the alternator, make sure its not shorting out someplace, could be a wire hanging close that is exposed or someting.

 

[GTM]

Ok the fuse held up good, but the same thing happend.All the warning lights came on and I had to get jump started 3 times until I got home.
What can it be?

Did you perform the "2 minute Alternator circuit test" in the Tech Guide / Electrical section before or after this latest failure??????????????

Let me know if you have a 4 wire plug on the back of the Alt for I'm working on this circuit schematic but it's a lot more complicated than 1G or later Non-Turbo Alt.

Cheers,
GTM

 

[93_GEE_ES_EX]

Did you perform the "2 minute Alternator circuit test" in the Tech Guide / Electrical section before or after this latest failure??????????????

Let me know if you have a 4 wire plug on the back of the Alt for I'm working on this circuit schematic but it's a lot more complicated than 1G or later Non-Turbo Alt.

Cheers,
GTM

I took the alternator to my parts store to get it checked,and it failed.

 

[GTM]

I took the alternator to my parts store to get it checked,and it failed.

I hope they are going to replace it for free.

Hurrumph!!! At the bottom of my post #2, I mentioned having it checked. Iin post #5, you said you had it checked.

What caused you to have it checked again?

Cheers,
GTM

 

[93_GEE_ES_EX]

I hope they are going to replace it for free.

Hurrumph!!! At the bottom of my post #2, I mentioned having it checked. Iin post #5, you said you had it checked.

What caused you to have it checked again?

Cheers,
GTM

Why would they replace it for free?
It's a Mitsu alt.

Yes I had it checked a few days ago and it was fine.Then I installed the 100 amp fuse.
Everything was ok after some hard pulls.
After a few hours of driving all my warning lights came on and the car died.I checked the fuse and it was good, so the next day I took the alt to have it checked and it failed.
So now I need to find a shop to rebuild it.

 

[GTM]

Why would they replace it for free?
It's a Mitsu alt.

Yes I had it checked a few days ago and it was fine.Then I installed the 100 amp fuse.
Everything was ok after some hard pulls.
After a few hours of driving all my warning lights came on and the car died.I checked the fuse and it was good, so the next day I took the alt to have it checked and it failed.
So now I need to find a shop to rebuild it.

I thought it was new/rebuilt and _not_ a used unit about 5 months ago?

Did they tell you what part was bad?

Rebuilding some some alternators is not beyond the skills of a courageous young DIY such as yourself. Common parts needed are the diode pack, brushes, and the regulator. Less common are the rotor, stator, and bearings. Ask a couple of independent shops where they buy their parts and call them for "price and availability" so you will know if they are in stock or have to be ordered.

You would need a volt ohm meter and probably soldering gun plus good screwdrivers and small sockets and wrenches. Since I've not seen one of these 4 wire DSM alternators I can't tell you exactly what to expecet. Most critical is keeping control of the 3 stator wires, mixing them up can make problems.

As for rebuilders I can't suggest anyone near you, look in the Yellow Pages.

Cheers,
GTM