senicalj4579

iTrader: (41)

Lights started doing this after the last build. Only mod I can see that may be guilty is the 25% power bond under drive pulley. Other mods were heads, cam, intake, and small boltons. Battery voltage from pcm reads in the 13s most of the time but sometimes when the cam starts surging then the volts go down to 12 before the car dies.
Alternator and everything was fine before the build so im thinking something with the new mods did this. Can the pulley be doing this?

senicalj4579

iTrader: (41)

How about a bad tensioner? I found the drive belt half off a few weeks ago. Put the belt back on all the way but the flickering lights are still there.
TTT

Mattyfresh89

I have the same mods and mine does not flicker. My camaro was doing this before my top end work, so I changed the alternator. Problem went away.


If you think the alternator is good / have tested it : I'd say check the ground strap and ensure its still intact and soundly connected. They get frail over time.

just my 2 cents

senicalj4579

iTrader: (41)

Thanks. I will check those things. I read somewhere that a4s are the ones that have the issues but not sure.
What alternator did you replace the stock one with? Did you do the big 3?

Justinktm

iTrader: (2)

im wondering what alternator is good also !

wssix99

iTrader: (5)

Which "lights" are flickering? Headlights? Gauge lights? Radio lights?

Did you go to a smaller belt with the new pulley? Did you check the tension marks on the tensioner after your pulley install to make sure you were in the proper range for the tensioner?

senicalj4579

iTrader: (41)

All lights.
Belt came with pulley that the shop put on.
IDK about any tension marks I guess I should learn about that.

wssix99

iTrader: (5)

Here's a good article, which shows the tensioner marks on a Fiero. We have similar lines on our tensioners. http://myfiero.oceanmoon.com/how-to/...h-serpent-belt

senicalj4579

iTrader: (41)

Thanks for posting that.
It looks like mine is fine. Idk why the belt came off halfway though.

senicalj4579

iTrader: (41)

Maybe I should post the automatic section seeing how its the autos that seem to have these issues that maybe related to the aftermarket pulley.

Empatho

iTrader: (16)

I did an under drive pulley on my car when it still had the auto tranny and the lights would flicker once in a while. What fixed it for me was doing the big 3 and swapping the alternator to a bigger one from an escalade at a junk yard.

Mattyfresh89

I got a rebuilt Pro-Select out of a "Uni-Select Warehouse" and it was like $100

No big 3 here and no problems. Worked great especially when I changed all the pulleys to eliminate squeaking.

If it threw the Alt belt then you possible have a tensioner issue.

Run the car with the hood open and rev it a few times by the cable. Keep an eye on the tensioner that you have pictured above. You may see the belt start to work its way off of the pulley due to a worn assembly.


I've seen multiple LS1's at car shows with the main belt half off a pulley. General response: "ya I gutta change the tensioner, that happens"

sjsingle1

iTrader: (1)

new tensioner..........buick pulley.........good deal.............add truck alt and big 3..........BETTER deal

Justinktm

iTrader: (2)

question whats a big 3? also another question whats a good idler pulley and another question lol what kind of truck alternator will it bolt right up?

wssix99

iTrader: (5)

Maybe it wasn't on correctly right after the change? I'd probably give it another try. I don't have a good place to work on my car and its usually dark - and easy for me to miss a rib on a belt or route it around a pulley incorrectly.

senicalj4579

iTrader: (41)

Well I def cant rule that out. The belt could of been half off the whole time I cant be certain. Iv been keeping an eye on it and its still on so who knows.

Thanks for all the info in the thread guys. I assumed most would say big 3 and truck alternator.

Any idea what parts could die out if I keep driving like this? Does the flickering lights mean its beating up my alternator or what?

Oh and what about the overdrive alternator pulley that some guys end up buying. Is that for the problem I have?

wssix99

iTrader: (5)

It would work...

IMO - This is a more straight forward solution to your problem.

mjs1012

iTrader: (36)

have you tried looking at the wire at the back of the alternator? mine did the same thing and the nut was loose. tightened it up and it fixed my the problem.

senicalj4579

iTrader: (41)

So do you think getting the bigger alternator pulley would cancel out the gains from the smaller udp? Iv see this question before but theres never an answer.


Thanks Mark ill take a look at that to.

wssix99

iTrader: (5)

I think it is likely to solve your problem because the issues started when you put on the UD pulley and this is what the OD alt pulley is for. Given that the alternator is old, you could be putting lipstick on a pig - it is possible that the alt decided to go south on you at the same time.

So, your other mods may be creating a higher demand on the alt, you could have a loose wire, etc. but a new pulley should be an inexpensive thing to try. Its also free to pop the bad boy off and take it to a parts store to be tested for free. (Just take care of the exciter wire if you do that!)