RPMulli

Gentlemen,

The weather is getting nice and I decided to do some work to my car prior to pulling it out for the spring. My interior lights were flickering prior to winter storage. I knew that my alternator bearing was wearing out so I decided to replace the alternator hoping to fix two birds with one stone. After I replaced the alternator... this is what happened...



http://youtu.be/WVPycU_DVfE

The interior lights still flicker (see instrument cluster lights and overhead light) and the engine appears to stumble in conjunction with the voltage drop. As you can see the voltage gauge it moving from 13 to 14v. Any ideas???


Added: After trying to troubleshoot my flicker issue.. I noticed a clanking coming from the crankshaft pulley region, videos below...

Macster

Last thing touched is first thing suspected. Check the alternator connections and installation and mounting. Check too the drive belt is routed correctly and the tensioner's not stuck/frozen.

If you find nothing amiss then perhaps the replacement alternator is well bad.

But before you get all medieval on the replacement alternator check the things I listed above first.

Oh, while you are there look very closely for any signs rodents have been at the car, the wiring and so on.

Oh, the stumble might just be do to stale gas. Depends upon how long the car's been parked up. I'd not worry too much about the stumble unless the engine start showing signs of getting sick. Right now, at least from the clip, it doesn't even act like it has a fever.

Also, with my car with a voltage gage upon a cold start the voltage reading approaches but doesn't quite reach the 14V mark. These gages aren't the highest quality so that bit of difference might be due to normal differences in the gages.

Sincerely,

Macster.

RPMulli

Macster,

The problem existed prior to me replacing the alternator, the new one just intensified the issue. Belt and tensioners are good to go. Where are some areas that rodents my be attracted to? I replaced the main power cable that runs from the back of the alternator as well.

The engine is clearly effected by the "dip" in power. The car has only been in storage for 2 months.

Ericginpa

If it helps I had a jeep cj that did that. I replaced alternator,batt cables and redid the ground strap from the engine to the frame. The ground strap helped but found out eventually that I had 1 bad cell in the optima battery. Maybe try load test on battery?

RPMulli

Thanks for the info, I just read that the battery could be the culprit on google. Where/how can I get it load tested? Autozone?

kromdom

YES. Also try O'Reilly's or Pep Boys (if you have these in your neck of the woods).

fpb111

also Check the cable that goes from the alt to the junction block on the right side of the engine. The crimp/cable can overheat corrode and go bad.

Pac996

Also Sears can do load tests. Voltage regulators can throw the same pulsing. Military trucks like to do the same thing sometimes for some unknown reason. You can try watching a multimeter but I'm sure its just going to be voltage going up and down. Bad case is your volts are OK but the regulator is thowing higher volts on and off. Watching your cars meter it seems you are getting higher volts than my puts out with new alternator on a new engine. Not sure if the gauges in all cars are created equal.

Good luck finding the problem......I guess I should say good luck getting rid of the problem

In any checks of the voltage with a digital multi-meter you want to watch for the voltage having a/c in it. It's spottable by watching the positive or negativ icon changing back and forth while you have the meter in the DC reading setting.

RPMulli

Update: Battery tested good. I even swapped in a brand new battery to see if anything changed.... Still same as before when the car is on.

My next thoughts were to check the grounding strap on the engine... or maybe the ignition switch?

jml3p

Hi
Try changing the relevant fuses

CMartin348

I had the same issues when I first bought my car. Corrosion in the ground wiring. Check that before you spend $$$$ on other things.

Macster

Two months is time enough for a pair of mice to raise two litters, almost...

Rodents like cars. A car is a nice, dry, draft free environment packed with lots of tiny spaces/passages (err, well you know what I mean) that mice love and feel secure in.

There's plenty to gnaw on too.

I've see a few cars and the mice (or rats) will gnaw on wiring, hoses (rubber or plastic), seats, carpets. I've seen the rubber radiator ducting at the front of the car chewed through. I've seen the vapor line from the tank to the engine compartment gnawed through: the animal probably stopped when gas fumes starting coming from the line. Some times the damage causes engine symptoms and even a check engine light. Sometimes not.

The creatures will shove nest and food litter onto the panels that are under the car.

I read in another post you've eliminated the battery.

That leaves connections as others have already pointed out.

It is not enough that you check they're tight but that you disconnect the connections (watch the battery is removed so you don't accidently do something with the battery that electrically damages the car!) and visually confirm the connections are corrosion free, show no signs of looseness.

That the symptom was there before the alternator and the battery is ok (I trust this is reliable info... a battery of one of my car's tested ok early in the AM after I had driven the car to the service department but the tested the battery later in the day and found it down enough to confirm the battery was bad.)

You're looking at rodents, connections, maybe an ignition switch (you can move/wiggle this and see if it has any effect on the engine's behavior) or possibly water intrusion from blocked body water drains, or a leaking window seal or a windshield gasket.

To check for water check carpets for any signs of dampness. Open each door and move it back and forth quickly and listen for any sloshing water sounds.

Sincerely,

Macster.

RPMulli

Another update: I removed and cleaned the main grounding straps for the battery and engine block. Also searched for any evidence of rodent damage under the dash, by the ECU and as much as a could in the engine bay. Afterwards, I ran the engine for 15 mins and the voltage appeared to stabilize slightly (around 13.8v). The flicker is less than before but I still think there is a problem elsewhere. Any other suggestions welcome

Anyway, I also noticed a weird clanking noise from the crank pulley area. I will post some videos when i get home.

RPMulli

Clank with serpentine belt removed....


Rattle around 3k rpm occurs occasionally


Clank from under car with serpentine belt


Another clip from under car

tbanasiak

do you have a stethoscope? if not a long handle screwdriver or wooden dowel even to press against things and stick the other end to your ear to help isolate the noise. I'm no expert but the first vid seemed to be noisy around that pully assembly, but then again i'm not standing there with the car physically. Does it have wobble/movement when moved by hand? Gonna go listen to all vids some more. worn/bad Chain tensioner maybe?