DK570

Hi All,

A while back I got codes P0491 and P0492 - Secondary Air Injection. Also had fault 31 Fresh Air Blower Fault. Not really sure how to diagnose I decided to remove the SAI motor to clean and re-grease the bearings. I re-installed and cleared the codes. I really didn't think this would fix the fault, but figured it was easier to do this than to try and find a vacuum leak. Everything was fine for about 400 mi, until today.

Could be completely unrelated but I had the battery/generator dash light come on today as well as the CEL. Voltage kept dropping on my drive home. Gage probably read about 10.7 V at the end of the drive. Codes today are P0491 & P0492 (back again) P0562 - Supply Voltage and 24 - Air Con Power Supply.

I checked the battery cables up front and the Pos terminal in back, all are tight and corrosion free. Checked the fluid level on the "maintenance free" battery, one cell was a little low, topped it off.

So, I'm guessing my alternator has stopped working?? Any thoughts? I checked Pelican, alternators are expensive ~$450, I don't want to start randomly replacing parts w/o knowing it will fix the problem. Is the only way to check an alternator by removing it and taking it to the machine they have at Auto Zone?

Ahsai

Check the drive belt first.

There are many ways but assuming you dont want to play with a multimeter, I think the easiest would be just remove your battery and take it to autozone for testing. If it's good, charge it fully, then put it back on the car.

Then start the car, drive it and note the voltage. If it ever gets below 13.2V, your alternator/voltage regulator/cable is bad. Regulator is only $40 from Pelican when alternator you can ge a Bosch reman. Bad cable you will need a multimeter to test voltge drop.

Good luck.

Imo000

The brushes in the alternator are probably worn. Its part of the regulator but it is at the back of the alternator and for that the alternator has to come out.

DK570

I removed the alternator with the Pelican instructions, it tested bad. It's probably just the voltage regulator, but I figured since I already had it all taken apart I ordered a reman alternator from Napa with a lifetime warranty for about ~$250. I really didn't want to have the regulator be the fix knowing that alternators have a finite lifespan. Plus the last two times I tried to do something more cheaply I didn't like the results. I did the cheap ignition switch fix, that worked for about 7 months before it failed again and I replaced the whole lock cylinder. Many people recommend Sumitomo III tires, I bought them since they are so cheap, but am not super happy with them. Oh, and when I changed plugs I didn't do coils, only to have 3 coils die a year later. With my luck, I've decided to be as complete as possible from now on when it comes to replacing parts / preventative maintenance.

Ahsai

I think that's a wise decision. $250 is quite reasonable.

PelicanParts.com

DK, glad you found the issue. Let us know how it turns out once all is back together again.
Mark/Pelican Parts

silotwo

LOL - this seems to be a law of the universe or something like that. I've been rehabbing a 2nd home for what seems like a lifetime and just keep learning that the most costly way to do anything is to do it twice. Insanity = doing the same thing and expecting different results. (I also stopped hiring the "nice guys" who include a dissertation on how honest they are along with their estimate. Usually means that they smile at you while their hand goes deep in your pocket? Yes, I am old enough that I have earned the right to be cynical.