Savtec-rex

So, bare with me while I try to explain my problem and setup so you guys know what I'm messing with.

90 CRX
RS machine B16 Head 300+cfm
Darton sleeve GSR block 84mm
Arias 10.1:1
LS Eagle Rods
LS Crank
1600cc
Dual bosch 044

So, I am trying to start it up on a basemap that I got from my tuner to see if the motor is sound and there are no leaks ect (So I can save money on just giving it to them to solve everything..lol, just have it tune ready for them).

So when I go to try to start it, all I get is a slow/dying cranking. REALLY SLOW, and it just dies out and stops after trying to turn the motor over for about 4-5 seconds. After I let go of the key, my battery fuse ALWAYS blows. I tried a different starter, no dice. I am on a Odyssey PC680 battery, which I thought maybe it wasn't strong enough, so I jumped it, put another battery in series with cables, and even flat out put a known working battery on the car. No dice either.

An odd thing I've noticed. I figured it could be my ignition switch. Because its acts funny. When I click the key to II to prime the pumps, it wont do it. The only way it will do it, is if I quickly tap the III (or start) position of the switch. That will "wake it up" to do the priming. So I decided to test the switch on my 91 SI hatch.....IT WORKS PERFECTLY IN ANOTHER CAR. Don't have to tap it or anything.

Other than trying to start the car, my other electricals work perfectly. Headlights, radio, gauges, everything. I had to make some grounds out of wire I had. I took 3 wires and soldered them together on both ends, and heatshrinked/taped it with some terminal rings on the ends. I did that for Starter to Chassis, Transmission to Chassis, and Valve Cover to chassis. Idk maybe those ground wires are good enough? I did try to just take my jumper cables, clamped them to the block and the other end to the chassis for added groundage.

Im stumped, I've gone through 6 battery fuses. I do have a Rywire harness. The fuse box is tucked inside. I checked for any visible open wires that may be grounding out, but nothing.

If anyone has any idea, or can walk me through some suggestions, I would greatly appreciate it, and I will also be sure to update on any results. Thanks

instrument

slow crank has always been indicative of a battery issue for me, sounds weird.

you havent mentioned what obd youre running, etc, but id check my grounds etc.

Savtec-rex

That's what I figured also, I will try more on the battery to see if anything changes. But would a dead/weak battery cause my fuse to pop all the time?

Its obd1 on Hondata s300. Thanks for your input, I will keep trying my grounds and battery.

Any other ideas from anyone?

davegt27

Did you test the starter on the ground?

If this was a new build did you rotate the motor on the engine stand?

If both of those tests are good by pass all the car electrical wiring and go right to the starter

If the motor spins ok then you now know it’s the cars electrical system


Davegt27

Savtec-rex

I did test the starter on off of the car, I have 2 starters and both spin fine. It is a new build, and I have tried to rotate it on the crank pulley, it rotates just fine. Im going to try to hook up jumper cables to the starter and to a battery and jump the signal plug with the hot wire and see if it spins the motor quick enough. Essentially doing the "on the floor" start test but while its on the motor.

Thanks for your input

Savtec-rex

Ok, just went out and did it because I was very curious....and.... after taking off the battery wire and signal wire from the starter, and putting jumper cables on the starter to a battery, and using a scrap wire jumping the signal and power wire....the motor turns at normal speed!!!!!

So...what does this mean? My brain is fried to even diagnose this. Why the poping battery fuse? Why the jacked up ignition in THIS car even tho it works perfect in another car? Those are now the questions I cannot figure out.

davegt27

Well it means there is nothing wrong with the ignition (not including the connection)

So the next step is to look for a bad connection or partial short

Take your time and have a close look at the wiring
It sounds like you have a good grasp of what’s going on

After the look-see the next step is the multi-meter

You want to disconnect the bat and continuity check from the positive bat terminal to ground should be good or you would have seen smoke

Do the same check at the starter main power wire

Next mover over to the starter solenoid wire (this thing causes a lot of problems)

Check from the solenoid wire to ground

That should be enough for one post

HTh
Davegt27

Savtec-rex

I will do this first thing in the morning, thanks a lot. In the mean time if anyone has any insight and things I should check, please feel free to let me know! No stone shall go unturned.

stowne78

I hope you meant you hooked the batteries up in parallel in your first post....
I am wondering if there is something wrong with your fuel pump, that may be sucking a lot more power than it should, which would explain the slow cranking.

mike_1212

I think davegt27 is right on the money here..... partial short or bad/loose connection.

Savtec-rex

Yea, parallel, get those mixed up.

Yea it seems something is drawing a lot of current. Which would explain the popping fuse. But I'm not sure what. These pumps are brand new, and wired very well imo. Probably the one of the best wiring jobs I've ever done, took my time on them.

But I guess I should explain how I have my cut off switch to see if anyone thinks it could be something with that. I have a wire from the alternator going to the back onto one post of the switch. On the same post a wire going directly to battery. And all alone on the other post of the fuse box wire. So in turn, flipping the switch would cut power to the fuse box, shutting everything down.

Savtec-rex

Im thinking about the partial short theory, and im trying to find out how I can pinpoint it. If all the electrical works perfect NOT trying to start the car, so any of those wires involving anything that doesn't start the car shouldn't be bad. So it would be along the lines of Ignition Wiring > Fuse Box to Starter/Battery and grounds right? Is that a fair assumption? because I only pop the fuse when im cranking, so a wire that is used in the cranking process is messing up somewhere.

Idk...its late, thinking out of my ***, maybe I should get some sleep....

KevinEF7

Your cutoff switch sounds *** backwards

mike_1212

You really should run the alternator wire to the same post as the battery. (will help you keep from burning diodes in the alternator if the switch is turned off with the engine running)

mike_1212

op, do your guages fluctuate at all when your cranking it? (other than voltage anyway)

davegt27

This does not sound right is this for a race/track car setup
Have a look here
http://robrobinette.com/S2000CutoffSwitch.htm


This has a little bit of an explanation which makes this one of the better guides


Davegt27

Former User

You must create thread titles that summarize the tech problem. Title edited.

Savtec-rex

Hmmm, It seems to work. it cuts power from battery and alternator to the fuse box. I don't see why it would be *** backwards.

Yes that is what I did. Alt and Bat are on one post, and the final power wire to power the car in fuse box is on the other post.

You know I never really noticed. If you mean my WB or boost gauge then now, I actually never noticed. Why? Thinking something about this?

Its wired the same as this guide pretty much, except its in the back of the car. I mean, I'll double triple check it because I'm not going to sit here and say you all are wrong, I do take advice seriously to solve problems! But, this switch as been here for years and has cut the car off every single time. soo...Im confused on why you guys think its wrong, but...like I said, ill give it another look-see.

Savtec-rex

New thing I've noticed just now after checking continuity on everything I can...

I do have a battery hot wire bulkhead coming through the passenger side panel into the engine bay for my battery. I was checking continuity between that how wire, and chassis ground. I get a beep from the DVM. I disconnected the battery ground because I thought it was just completing the circuit and that's why it was giving me the beep. Same thing, I touch the chassis and the bulkhead stud, and I get beep. So, It still seems grounded even when disconnect the battery. It should not do that right? Its a moroso bulkhead I got from Summit, so....idk...thoughts?

mike_1212

With the battery disconnected, no you should not have a beep. Did you literally remove the terminal from the battery? or use your cut off?

Savtec-rex

Yes I figured when the bat is NOT CONNECTED, there should be no beep. So yea, I took off the cables from the battery.

So I'm in the process of tracing how far back the continuity to ground goes. So I followed the hot wire of the battery back to the cut off switch in the back, when the switch is off, only 1 post, the FUSE BOX WIRE post has continuity to ground. The other does not (Bat, Alt). So I traced the fuse box wire to the box, where I checked ALL screw points inside the box. ALL of them have continuity to ground. So, correct me if I'm wrong, the fuse box power points should not be grounded out. So......That means, the 3 fat wires on the right side of the fuse box should lead to what is being grounded out. I see another small connector in the box also. I will check that as well. Where do those 3 fat wires go? To the ignition correct? Or to the dash fuse then to the ignition switch. So I'm lost from there on out. Ideas?

UPDATE: So I found the WHT/RED wire coming from the fuse box is the one causing it all. So where does that go? To Dash Fuse Box correct?

davegt27

Cool you’re making progress

So now pull each fuse one at a time and make the check to ground
This should narrow it down even more


Back to the Batt cutoff I just checked my ITA CRX and its wire wrong ha ha
So when I throw the disconnect to off I still have power at the starter and the alternator

I guess the tech inspector did not catch that
What I mean to say is let’s say something falls on the starter or alt post and shorts out and starts a fire then someone runs over and throw the cutoff switch thinking they killed all power
On my car the alt and the starter still has power going to them
The things that make you go Hmmmm


davegt27

Savtec-rex

Well, I did narrow it down to a single fuse. The one for the Clock, Radio, and Cig Lighter. When I take that out, there is no ground continuity to the fuse box. Strange, so..I trace the wiring from the under dash fuse box. I pull another plug from the back of the fuse box to find out which clump of wire harness is causing the problems. I manage to find the one that is. Once that is pulled, and I put the fuses back in the front of the box, there is still no ground continuity.

So, that cluster of wires is messed up somewhere...annnnnnnnnnnd to my surprise, I follow the wires to a nest of burned wires that lead into the main chassis fat harness that is strapped to the firewall. There are about 4-5 wires that are burned, melted. So final test. I check ground continuity on some exposed burned wires to chassis ground....BEEEEEEEEEP from the dvm. So I found the problem which just made my stomach sick. After all the trouble of putting the dash and interior back together, I have to take it all back out, and peel back the loom/tape to see the extent of the damage, and try to repair it. If its too far into it, I may have to get another harness from the yard.

All in all. FML....F...M...L....

mike_1212

Look also for what caused them to burn, otherwise you'll be doin it again. Happy to hear that you found the issue though..... That gets you half way there..

Savtec-rex

Yes when I see exactly what wires they are that are burned, I will need to find a pinout and see what they do.

Stopping for the day, very angry lol. Will update this as I find out more. Thanks for the help guys