Electrical Goblins....

[RedZMonte]

So im having some annoying little issues and i thought i would ask to see if you had some ideas... keep in mind my car is kinda wacky. 1995 Monte Z34, Trunk mounted Battery (optima yellow top.... Honda size), 1996 Z34 Engine harness, Rear disc conversion.

all of the issues im sure are related..
1. intermintant starting on 1st attempt.. it will make a partial crank over and then stop.. then i turn the key to off and on the 2nd attempt it fires up, and sometimes it fires right up 1st try.. when it does this, my radio presets/time clear and i have to reset them. it will allways crank over and start on my 2nd attempt so i wouldnt suspect the starter sollinoid..

2. about 70% of the time my dash lights are dim at night as are my head lights. when this happends the ANTI-Lock light comes on. Sometimes it will after running for a bit everthing will become bright again (headlights, dash lights) and sometimes it comes on bright when i start the car and be fine (rarely).

Im thinking it could be a couple of things... A.) the power wire i used for the OBDII swap wasnt large enough to feed the interior harness B.) Not enough Battery power (honda size in the trunk) C.) alternator is starting to act up....

what are your thoughts?

Thanks in advance,
Shane

[pocket-rocket]

I would think step up the battery size, along with going to a larger gage wire for the run to the engine bay. I thought most people that use welder wire to the engine bay from the trunk usually have no problems, and to me it sounds like for one, you are getting too much voltage drop between your battery and engine bay, so I would start with the wire first. The ABS light will light up when the voltage is too low to run the ABS correctly, which is what helps me think you have too much voltage drop at this point in time.

[RedZMonte]

what if i added another smaller battery up in the front fender well area or something? you think that would do the trick if the voltage was to low?

[WrathOfSocrus]

Is the battery ground just bolted somewhere in the trunk area? I agree that voltage drop is a major concern with remote battery mounts. The alternator is grounded to the block and usually the battery is also grounded to the block. Not having a ground wire going to the block directly from the battery will cause the current to go across whatever ground straps are attached to the block from the chassis. While grounding to the chassis is fine for most applications, your main sources of power (battery, alternator) need copper or at least aluminum connecting them. I'm sure plenty of people have gotten away with adding extra ground straps but many more have had chase the dreaded 'goblins' or 'gremlins' due to the higher electrical resistance of the chassis.

[RedZMonte]

It is grounded well to the trunk floor. and the stock neg terminal is grounded to the chasis as well.

Small battery like this one...

http://www.odysseybatteries.com/battery/pc680series.htm

PC680
Small 680 cranking amp battery with metal jacket and SAE automotive terminals.
Also available without the metal jacket for low temperature applications.
Battery measures 3.11" wide x 7.27" long x 6.67" tall with the metal jacket and weighs 15.4 pounds.

Recognize that the reserve rating is small, so storage time with computer draw can discharge the battery in a few weeks. Ideal for Street Rods up to 5.7 liter V-8. Can be mounted in the glove box flat on its back - only 3 1/8 inch high.

Excellent starting battery where high reserve capacity is not required.
Great lightweight racing battery for shedding extra pounds.
Can be mounted upright or flat.

[WrathOfSocrus]

what if i added another smaller battery up in the front fender well area or something? you think that would do the trick if the voltage was to low?

Doesn't that defeat the original purpose of the remote battery mount? Having the battery's ground bolted to the chassis in the rear and having the block grounded up front means there is roughly 10 feet of car between the two connections. Sure it can probably handle thousands of amps but the resistance of the chassis will still cause voltage drop.

To double check this you could try using a jumper cable between the remote battery and the engine block. Or you could use a multimeter to check the resistance and voltage drop of the setup. Just by putting my multimeter on the frame of a truck I got around 2 ohms over 3 feet of frame. Add in more distance and several connections plus whatever the small amount of resistance in the wires themselves and it could be enough to cause trouble.

[RedZMonte]

thanks guys. i will try that.

The reason it was relocated was for the turbo, it takes up all the room i have up there. i can add a small battery in the fender well somewhere if its starving for power, but i doubt the smaller battery will have enough juice to run everthing on its own..


I forgot to mention i have a FFP UD pulley as well so the combination of have it and relocated battery im sure at idle its really starving for juice

S

[d.o.h.c]

I am running a 00 welding wire. ITs about 1/2" thick. Not sure, but to me it sounds like you might have blown a fuse able link. You make sure they were all good?

[jmgtp]

If it was a blown fusible link I would think it would not work at all.

The battery size could be the problem, but was this always the case or is this a new development? If it's something new then I would guess you have a bad ground, aged wires or weak battery/alternator.

I have my battery in the trunk as well but use a Optima Redtop that is the same size as OEM equivalent batteries. However, I ran some HUGE diesel locomotive cable for power and ground all the way up to the front. I grounded to the trans case and ran the wire to the + power post. The wires are about 3/4" thick each and required a special hydraulic crimping tool to put eyelets on! The great thing about that cable too is that it is oil/grease/gas resistance and is very flexible. It has worked flawlessly and cranked just the same. Recently the starter is struggling just a bit on a hot engine start. I think it is just heat soaked and its age is showing. I have a 3x00 mini starter that I need to install to try to rectify this problem. You may want to consider that as well - the gear reduction/smaller starter may mean less loading of the battery, at least thats my current theory. If I recall correctly, for your application the Optima Redtop would be better suited as I believe it is supposed to be the superior cranking battery whereas the yellow top is the deep cycle.

Seems like you definetly have an enormous voltage drop. Best case scenario would be a bad ground or weak battery unable to deal with a high load. Worse case a short somewhere. Try jump starting it off another car and see if it 1) starts good and 2) radio presets arent erased. If they don't erase then I think you can almost safely assume a weak battery, bad power wires or bad ground is your problem.

[RedZMonte]

1995 Monte Carlo Z34 (3.4L DOHC LQ1). FFP UD pulley

What should my alternator output be at idle and say 3000 rpm's? im seeing only 12V and when i rev it to 3000 it goes up to 13.2-13.5v. Does that sound about right? Im still having electrical issues (slow windows, guage cluster/headlights dim, Anti-Lock light on, ect.)

I put a trickle charger on and everything seemed to be normal for a little bit. After driving a little it seemed to start the issues all over again, and tested the voltage again w/ a multi meter and it was back down to 11 something... I had the parts store check the alt. output and the battery. the alt. was a low at idle... dunno if the UD pulley would cause that, once it reved up it was fine. the batter was under 12v... 11 some volts. and he said it has plenty of CCA. the battery ground appears to be solid as allways (stripped paint off and bolted to trunk floor, done by my mechanic). this is the same setup i have been running for atleast 3 years.. just started acting up a month or 2 ago. same battery, same alt, everthing is exactly the same.

The radio presets only erase if the car doesnt turnover on the 1st attempt... it does a partial crank then stops. then on the 2nd attempt it usually fires right up.

[RedZMonte]

Also sometimes when im crusing down the road/interstate and when i use my turn signal the engine actually studders when the blinker blinks.. like a solid miss every time it flashes... assume because its starving for power.... ONE time the "Voltage" light on the dash came on but has never happened again.. I know in the past when that light came on my alt took a shit.... this time i stopped and shut the car off and restarted it and it was off.

[SofaKingWeToddDid]

should be 14V at idle... sounds like a toasted alternator, but im still thinking something between the battery and engine is going bad. i skimmed over everything, and i would use 0guage wire... i got it for my amp and its def bigger than 1/2" as for the battery, it should be fine. check the CCA between the next size up. but anything over 650 is going to be just fine for a car without a set of subs and an amp. also i would check to make sure all your connections are tight. when i got my car it would have trouble turning the motor at first, but it would always start (felt like a bad battery or starter maybe) but it turned out to be a loose remote boost terminal. even pull on the wiring for the starter a little (dont swing on it like a monkey in the jungle) but check to make sure all the connections are tight.
oh and add some more grounds around in the trunk, it wont hurt anything. if you really feel crazy too, add a second 0 guage wire from the trunk to the engine bay for ground.

i personally avoid welders cable. (because of the looks, not functionality) but it does work. dont get me wrong, im not sayin thats the prob.

[RedZMonte]

lol well its a safe bet at this point i think, battery terminals are solid as a rock... grounds are all solid and clean, battery holding 12.2V.

with my headlights on bright my blinker on and my sterio on it went from 13.6V at idle to 12.2V at idle and sputtered.

safe bet is on the ALT.... lol well i guess i cant complain too much it has lasted me almost 100,000 miles (died when i bought the car 8years ago...)

[jmgtp]

100,000 for an LQ1 alt is a good life.

Funny story, I started my car this morning, began to drive to work and I see 'check gauges' on my HUD. The check engine light was not on and then I glanced over at voltage: 12v no charge. Dammit. It worked flawlessly up until this morning.

This is my 3rd or 4th alternator, the original went 90 or 100k miles but since then they last 2 years and quit! I'm actually more worried that it is a wiring issue than the alt - this car has been an electrical mess lately.

At least with the 5 speed I can swap the alternator out in less than an hour... try that auto guys!

[HayesPerformance]

Well I didn't read all the posts thus far but there are a few things I would be checking.

I have seen others that have been done this on vehicles and had the SAME problems that I have had to solve, and they were all to do with a number of problem done when installing the battery in the trunk.


-First, over that distance use at least 2ga.
-Second, MAKE SURE ALL THE RING TERMINALS ARE SOLDERED OR PROPOERLY CRIMPED WITH A LARGE CRIMPING TOOL (this is the MOST common problem!!!)

-Make sure that you ground from the battery to the body AND from the battery TO the bell housing bolt by the starter AND ground from that bolt to the common ground on the front left by the rad (Make sure the ground for the ECM and OBD II get a GOOD feed to this ground).
-Make sure the Power goes straight to the starter and then (Still using 2ga.) back to the main power block on the top left strut tower (Factory cable I learned is WAY too small when it is working to charge a battery in the trunk).
- On the Alternator, Run a 8ga. battery wire to the starter AND ALSO run a 8ga. ground wire from THE BODY OF THE ALTERNATOR to the Large bell housing bolt(Believe it or not, It will actually result in improved charging output from the alternator).

I have went through this sooo many times and I personally found that this was necessary in running the battery in the trunk.

In regard to the wires for the OBD II conversion, If you feel that you did place too small of wires in some places on the conversion then go ahead and change them! Its not going to harm anything going a bit bigger...