Cascade Crew

iansane · Posted: Mon Dec 07, 2009 5:13 pm Post subject: Charging issues?

So I thought everything was kosher after my swap. I had a few hiccups here and there. I forgot to plug a pcv hose off the intake, Embarassed

the maf was only getting ~9v so it was pulling a low voltage code and the wiring still looks like hell but oh well.

After driving it around for a day or so it was charging fine. I tapped into the alt exciter wire to feed the MAF sensor and now it seems as though the alt is only charging at ~11.8-12.0v and it steadily drops as things are used. Obviously the no brainer thing to do is supply MAF power from something else, right? Would the MAF really pull enough power that it would affect the alt reference wire? It was keyed 12v when I hooked it up but now I'm not so sure. What are the downsides to running the alt reference wire (brown on our stock cs130) to battery all the time?

Help a crewbie out here. Very Happy

aaron_sK · Posted: Mon Dec 07, 2009 6:33 pm Post subject:

The CS130 has two wires that switch on the regulator. One is designed to be used with a light (to prevent run-on) and the other is designed to be run straight from the ignition switch. Allegedly you can use both (GM did on quite a few cars).

Lemme dig up my diagrams from the S10 swap...

*Edit: Bah, it's on the other laptop. Never mind though, Google to the rescue.

On the S10 I have the 'L' pin spliced off my main ignition switched line from the fusebox that also switches all my relays (fuel pump, fan, power windows, ect.) as well as the choke on the Holley.

I never bothered to find a plug that had the 'S' pin in it (lotta GM cars never had one, damn junkyard plugs) but it seemed to work like a champ and never overcharged the Orbital (yeah, I still got that damn thing, it's a champ Razz

)

Twilightoptics · Posted: Mon Dec 07, 2009 6:39 pm Post subject:

Definitely grab a diagram from that particular alternator. S&P and some other places wire them different than factory so plumbing is different internally too.

iansane · Posted: Mon Dec 07, 2009 6:59 pm Post subject:

It's the original style alt for my car. Same part number, just clocked differently. It was functioning correctly until I spliced in the MAF power wire. I guess I'll try splitting that off to another wire and see what happens.

Aaron, what do you mean with a light? The light is powered all the time? I wired it originally just like it was factory. The 'L' terminal isn't used on thirdgens, the F and S are however and from factory diagrams get straight 12v. F from the fan fuse and S from the same group of wires that powers the starter.

aaron_sK · Posted: Mon Dec 07, 2009 7:39 pm Post subject:

Yeah, both sides of the gen light get 12V, one from the alt, and one from the ignition. The ignition side is powered (albeit indirectly) through the battery. 12V on both sides of the bulb = no potential. If the output of the alt drops below the output of the battery, that side of the light circuit will ground out, causing potential, and the the light will switch on.

^ Gen light 101 Razz

If you run a light, hook it up to 'F'. If not, cut 'F' and hook 'L' to any fused ignition switched line that is relatively clean (not alot of crap on it).

BTW, don't know how fourth gen cars do it, but IIRC the MAF needs it's own relay straight from battery-ville, and witched by the ignition.

Hell, don't turdgens have two relays? One for MAF power, and one for the burnoff.

iansane · Posted: Mon Dec 07, 2009 9:18 pm Post subject:

aaron_sK · Posted: Mon Dec 07, 2009 9:28 pm Post subject:

I don't think the newer MAF's have a burnoff setup. Basically it superheats the wires for a bit after the engine is shut down to cook all the crap off of them that builds up from whatever.

If you have no gen light (neither does the S10) then there is no reason for the 'F' wire. You will need another plug from a junkyard car that has S and L.

You need 12V at either F or L to switch the regulator. Otherwise the alt will not turn on (ask me how I know this Razz

).

The 10si and 12si regulators will come on once you rev the engine up (this is how morons get away with running those horrible 1-wire alts) but the CS130 doesn't seem to like that idea.

Before you go wiring the MAF to random stuff, you need to figure out where GM pulled their power on the fourth gens and trucks. The General has a lousy record of designing wiring harnesses though, so take it with a grain of salt.

iansane · Posted: Mon Dec 07, 2009 9:43 pm Post subject:

Dude, you keep saying I need 12v at L. Thirdgens (FI 91s anyways) don't use the L terminal, the use the F.

Fourthgens pulled MAF power from a 20a fuse that also pwoered half the o2s and something else, I can't remember.

aaron_sK · Posted: Mon Dec 07, 2009 9:46 pm Post subject:

Eees veeery eenteresting mister Bond...

http://www.ls1tech.com/forums/conversions-hybrids/936409-99-02-schematics.html

Basically the MAF draws power from a 20amp ignition switched relay. You little 18ga brown alt regulator switching wire should not be providing 20 amps.

*Edit: BTW, the diagram you posted seems to be reversed. With L triggering the light rather than F. Might be what Paul was saying, might be an error. Gonna have to check the S10 tomorrow morning to see which wire I ran to the ignition.

iansane · Posted: Tue Dec 08, 2009 10:06 am Post subject:

The 20a fuse also supplies power to o2s, crank sensor, cam sensor and some other things. The actual wire to the MAF isn't larger than 16g.

I don't think the diagram is reversed, I don't have a battery light in my cluster. That's the same one as in the factory service manual.

Regardless, I still have issues when I isolated the MAF to it's own circuit and powered the brown wire with 12v. We'll see where this goes now...

aaron_sK · Posted: Tue Dec 08, 2009 10:14 am Post subject:

Have you had the alt tested to make sure the regulator is cycling properly?

iansane · Posted: Tue Dec 08, 2009 10:34 am Post subject:

That's what I'm going to do today. (hopefully Laughing

)

iansane · Posted: Tue Dec 08, 2009 5:11 pm Post subject:

Alt tests good. Mad

iansane · Posted: Tue Dec 08, 2009 6:20 pm Post subject:

So I did a voltage drop test from the alt case to the a strut tower bolt (ground) and got 8v! I'm throwing another ground strap from the alt to block. This may have to do with the anodized alt brackets? I don't know.

aaron_sK · Posted: Tue Dec 08, 2009 7:55 pm Post subject:

Queue bueno? Looked like you had a pretty hulking cable from the block to the body today.

Where does your neg. battery cable terminate? I like to attach mine as close to (or even on) the alt as possible.

iansane · Posted: Tue Dec 08, 2009 8:20 pm Post subject:

Yeah, the cable to the block is hulking. Actually one off each corner of the block to the body/firewall. But the alternator case itself isn't grounded to anything other than the bracket. Which is anodized Al. So, I'm having Seth grab me another ground strap from work and running it from the alt bolt to one of the ground strap bolts on the block. Can never have too many grounds. Laughing

The neg terminal is a dual cable. One goes directly to the body behind the passenger seat and the other runs up and uses the same bolt as the rear passenger side head ground strap.

aaron_sK · Posted: Tue Dec 08, 2009 8:37 pm Post subject:

Aha. That might be the trick. On mine I usually get all OCD and put the batt. ground strap on the lower alt bolt, which satisfies my need to ground stuff out. Razz

iansane · Posted: Tue Dec 08, 2009 9:15 pm Post subject:

I think that would be a eight foot cable for me. Laughing

aaron_sK · Posted: Tue Dec 08, 2009 9:53 pm Post subject:

Only a couple extra feet. Razz

BTW, you're running good welding cable to that Optima, right?

iansane · Posted: Tue Dec 08, 2009 10:57 pm Post subject:

I had WOFSCO make me up some 0g cable. Hail hail

.02v drop during cranking!