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Topic Review (Newest First)
01-29-2013 04:40 PM
xpmr5 Still happening. It is definitely much worse when it is hotter outside. It has not been nearly as bad in the winter with resetting. Going to take it to the mechanic in the next couple of days if I can't figure it out.
09-15-2012 12:26 AM
VEGAS Not that hard :P

there are 2 ways, some remove a few things and pull out the top..

other way is out the bottom is you disconnect the lower bone mount on tranny and pry motor to front and slip out the alternator.. I used the top :D
09-14-2012 07:46 PM
xpmr5 I checked all the connections, put dielectric grease on the two alternator plugs, and the same thing is happening. It seems to be directly related to the outside temperature. On a hot day with the sun out, the radio turns off, goes a few minutes, turns back on for 20 seconds, turns off, and repeats this cycle the whole drive home from school. At night or on a cool day, such as the one we had yesterday in Chicago (65 and rainy), the radio stayed on almost the whole way home. It doesn't matter if I have the A/C going or not.
09-08-2012 04:30 PM
WrinkledCheese Alternator replacement on this car with a zetec is a PITA. I have an 01 SE. If I can remember correctly you have to do the following.

Move the engine coolant resivoir. I disconnected the bolts and clip(towards the back of the engine bay) and moved it to the front.
Move the Power Steering Fluid reservoir. This just lifts up and pulls out. The three rubber grommets keep it in place.

Next you have to move the wires and fuel rail supply. The fuel rail supply uses a special tool. However, if you use some intuition you can use a pop bottle cork.

Now, once everything is disconnected you can push the engine as forward as it will go. The service guide says to drop the alternator down through the bottom, but if you position it correctly you can get it in from the top. Dropping it down is easier when taking it out.

I would make sure that it is your alternator and nothing something else in the charging circuit. I believe my voltage regulator or something else is dead/on the way out. If you know someone at a professional shop they can test it for you. If not you can pay to get them tested.
09-08-2012 02:20 PM
xpmr5
Quote:
Originally Posted by MEJY1988 View Post
If you have a hatchback, check the wiring harness go into the hatch. These are known to cause some weird problems. IIRC someone had a similar problem with charging and repaired wiring and it solved his problem.
I wired in tap in connectors to the brake lights, turn signals, and grounds in the rear of the car, and the problem came a week or two after doing this. It has gotten worse lately to the point where the radio shuts off every minute. I thought by unplugging the connectors that are in the trunk of the car, before all the tail lights and wiring I did, that I would be eliminating all of that stuff as a possible cause for all of the trouble.

Quote:
Originally Posted by whynotthinkwhynot View Post
Alternator change-outs aren't easy in this vehicle. I wrote a How-To on how to do it with a manual transmission. I'm not sure if AT's are easier or harder. Keep that in mind before you do it. I have also frequently recommended that anyone needing an alternator locate a local rebuilder for both price and reliability. These are available for starter and alternator repair nearly everywhere, and it's who most local shops use- then charge you new dealer retail. Local shops have warranties, but will be more likely to use better parts because warranty repairs will cause them problems that big chains don't bother with. The big chains use cheap parts to keep the individual price down to the point where they can feed you 4+ alternators before they start losing money. They really don't care if you have to swap out your alternator every 3 months. Ok, enough about that.
We have a family friend who rebuilds alternators for cheap. We've used them on all of our cars for years with no problems, and the cost that he charges is nothing to complain about. I also have time and tools on hand, and a serious lack of money, so I'm all for swapping it if that's what it needs.

Quote:
Originally Posted by whynotthinkwhynot View Post
First things first- I didn't read where you checked your battery terminals. Yes, a loose or corroded condition at the battery terminals will do this. The alternator needs power in order to make power. That's what the "field" wire on the 3 wire plug-in is for. There are several ways to clean off corrosion. Some people use a little baking soda and water. Some people just scrape and wipe it off with a rag, then wash with water, or vacuum the dust up. Be sure to remove all the corrosion from the terminals themselves- you can buy a simple terminal cleaner from the parts store for $1, or wire brush, or light scraping with a knife. I always recommend an old trick when re-installing terminals- put grease on them. This prevents future corrosion. Any grease will do. I just use leftover wheel bearing/axle grease. All petroleum greases are non-conductive.
I cleaned the battery terminals yesterday. No corrosion present, and I put them back on using silicon spray to prevent corrosion.

Quote:
Originally Posted by whynotthinkwhynot View Post
Also check the negative battery connections- especially the big one that bolts to the engine/transaxle bolt. Make sure it is tight, and there is no fraying of the wires going into the wire's terminals. I would also check the 2 small wires, and there is a wire that goes into a black box on the front of the engine (pass side vehicle), and then that wire comes out and grounds to the strut tower. Carefully inspect this box and make sure the wire is not frayed or the insulation is not cracked where it connects. If it is, get a replacement from the dealer. That one can pop your ECU fuse if it grounds out on the power input side.
Will do.

Quote:
Originally Posted by whynotthinkwhynot View Post
Now the alternator. There is a big bolted wire to the alternator, and the plug-in wires. Earlier Zetec equipped cars had problems with the insulation wearing off, and tiny wires going to the alternator plug-in connector. I do not know of such an issue with the Duratec engines like you have, but if you've not found anything else- check it out. Also check to see how secure the bolted hot is to the alternator. Before you put a wrench or socket on that one- make sure you've disconnected the neg from the battery. If you haven't found any problems here, then something somewhere is going to have to be replaced.
Will do.

Quote:
Originally Posted by whynotthinkwhynot View Post
A bad battery can do all of this. If you smell rotten eggs near the battery- remove and replace battery immediately. How old is the battery? If it's very old, that is likely to be the problem. Batteries that simply go their lifetime will hold good voltage, but not maintain that voltage under load. Like I wrote before, if the battery output goes down, the alternator output will go down also. Even new batteries can have a similar problem that causes the same issue, so have the battery load tested before you go through the trouble of replacing an alternator.
Will do.

Quote:
Originally Posted by whynotthinkwhynot View Post
Finally, it could be that the alternator is bad- bad brushes- but there is still some contact being made there. Intermittent voltage from an alternator is not uncommon just before it stops producing power. Like I wrote, I'd research how to remove the alternator, and then check everything until the only conclusion is that the alternator needs a rebuild. Mine was rebuilt at 130k and 6 years.
Okay, thanks a ton for all of the help. Hopefully the solution lies in one of your ideas

Quote:
Originally Posted by Now534 View Post
Check the wiring going to your Alternator first before you decide to replace it. Something intermittent like that sounds like a wire is shorting out.
Probably, I'll get back to you guys when I check all of these things listed.
09-08-2012 10:40 AM
whynotthinkwhynot Alternator change-outs aren't easy in this vehicle. I wrote a How-To on how to do it with a manual transmission. I'm not sure if AT's are easier or harder. Keep that in mind before you do it. I have also frequently recommended that anyone needing an alternator locate a local rebuilder for both price and reliability. These are available for starter and alternator repair nearly everywhere, and it's who most local shops use- then charge you new dealer retail. Local shops have warranties, but will be more likely to use better parts because warranty repairs will cause them problems that big chains don't bother with. The big chains use cheap parts to keep the individual price down to the point where they can feed you 4+ alternators before they start losing money. They really don't care if you have to swap out your alternator every 3 months. Ok, enough about that.

First things first- I didn't read where you checked your battery terminals. Yes, a loose or corroded condition at the battery terminals will do this. The alternator needs power in order to make power. That's what the "field" wire on the 3 wire plug-in is for. There are several ways to clean off corrosion. Some people use a little baking soda and water. Some people just scrape and wipe it off with a rag, then wash with water, or vacuum the dust up. Be sure to remove all the corrosion from the terminals themselves- you can buy a simple terminal cleaner from the parts store for $1, or wire brush, or light scraping with a knife. I always recommend an old trick when re-installing terminals- put grease on them. This prevents future corrosion. Any grease will do. I just use leftover wheel bearing/axle grease. All petroleum greases are non-conductive.

Also check the negative battery connections- especially the big one that bolts to the engine/transaxle bolt. Make sure it is tight, and there is no fraying of the wires going into the wire's terminals. I would also check the 2 small wires, and there is a wire that goes into a black box on the front of the engine (pass side vehicle), and then that wire comes out and grounds to the strut tower. Carefully inspect this box and make sure the wire is not frayed or the insulation is not cracked where it connects. If it is, get a replacement from the dealer. That one can pop your ECU fuse if it grounds out on the power input side.

Now the alternator. There is a big bolted wire to the alternator, and the plug-in wires. Earlier Zetec equipped cars had problems with the insulation wearing off, and tiny wires going to the alternator plug-in connector. I do not know of such an issue with the Duratec engines like you have, but if you've not found anything else- check it out. Also check to see how secure the bolted hot is to the alternator. Before you put a wrench or socket on that one- make sure you've disconnected the neg from the battery. If you haven't found any problems here, then something somewhere is going to have to be replaced.

A bad battery can do all of this. If you smell rotten eggs near the battery- remove and replace battery immediately. How old is the battery? If it's very old, that is likely to be the problem. Batteries that simply go their lifetime will hold good voltage, but not maintain that voltage under load. Like I wrote before, if the battery output goes down, the alternator output will go down also. Even new batteries can have a similar problem that causes the same issue, so have the battery load tested before you go through the trouble of replacing an alternator.

Finally, it could be that the alternator is bad- bad brushes- but there is still some contact being made there. Intermittent voltage from an alternator is not uncommon just before it stops producing power. Like I wrote, I'd research how to remove the alternator, and then check everything until the only conclusion is that the alternator needs a rebuild. Mine was rebuilt at 130k and 6 years.
09-08-2012 09:58 AM
MEJY1988 If you have a hatchback, check the wiring harness go into the hatch. These are known to cause some weird problems. IIRC someone had a similar problem with charging and repaired wiring and it solved his problem.
09-08-2012 07:05 AM
Now534 Check the wiring going to your Alternator first before you decide to replace it. Something intermittent like that sounds like a wire is shorting out.
09-07-2012 06:54 PM
xpmr5 Alternator output was 12.7 volts when the levels were dropping, and raised to 13.8 volts when it seemed to kick back on and started to recharge the battery. I think what is happening is the alternator is letting the battery drop to too low of a level before kicking on and recharging. I'm beginning to think the alternator needs replacing. The car is nearing 90K and I believe it is the original alternator.
09-07-2012 06:18 PM
xpmr5 I eliminated a possible cause in the fact that I spliced connectors into the brake lights to wire in a trailer harness by disconnecting the connections in the trunk that go to all of the brake lights and such. The radio still shut off after a few minutes.
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