13Beast REW

Obviously this is an electrical issue. The absolute only reason I'm posting this is because is in hopes of getting assistance in attempting to isolate which elecrical system may be the culprit which is causing the symptoms as descibed below. (Long but narrative like...)

It started with a starter clicking problem. Naturally I assumed the starter was going out since I still had full power to all accessories and no dimming lights when hitting the brakes with A/C, brights, rear defrost, fans on full blast, and windows operating. Bought a brand new starter, installed and still had same problem.

Start thinking in some strange altered universe it just might be the battery so I get a new battery also... same problem.

Now... I HAVE been messing with the wire harness while installing an aftermarket ecu. The car has started and run just fine with those changes for about 6-8 months. I removed my changes to the harness about a week ago. Since then I've made an adapter that allows me to use the aftermarket ECU through the stock ECU connectors. Both the aftermarket ECU and the factory (J-Spec) ECU have operated just fine up until about 4 days ago when I started getting clicks at the starter while trying to start the car with the aftermarket ECU.

I swapped back to the factory ECU and the car started just fine. I took the car for a spin to make sure the battery had a good charge and make sure everything ran ok. Went great!

Parked the car, swapped in the aftermarket ECU and I notice on my laptop that the voltage to the ECU was quickly hopping around with differences from .5 to 1.2 volts. Tried turning the engine over and no dice. Just clicks.

When I removed my modifications to the factory harness, it left some wires without insulation over a span of less then and upto about a half a centemeter. I've since patched all of those up with electrical tape as well as covered up unneeded wires on the US-Spec wire harness that the J-Spec ECU has no need for.

For a moment I was having some grounding issues to my oil pressure sensor but have fixed that issue.

I recently push started the car with the factory ECU and it started but idled very rough until the engine fully warmed. It was able to idle on its own without assistance from the gas pedal. It was very obvious that there was some sort of electrical load that the IAC was compensating for. I operated every electrical system that I have a switch or button for and everything worked as normal.

After it warmed up the idle leveled out at 700-750 rpm, so I started driving it up the street to see if it would drive as normal. Obviously, being full aware that there was an electrical issue I stayed off boost until I was certain the car would operate normally off boost. Once confident at low rpms, I accelerated without boost up to about 6500-7000rpm without a problem. I turned the car around to drive it back home and this time allowed it to boost a little. Under light boost ( < 2lbs) it performed as expected. Added a little more throttle and it bucked really hard.

Pressed in the clutch, coasted and let it idle for a minute... all rotors intact. Tried boost one more time, this time, not even an acceleration surge as would be expected just a backfire as though the engine was running lean. Naturally I instantly let off throttle and let it idle, then parked the car back in the garage and turned it off.

Tried to start it, expecting it not to, and as expected, it clicked just as before.

Now I'm wondering, what would increase electical load while under acceleration to the point the voltage would drop low enough to prevent the engine from running as expected. I'm basically trying to isolate what system might be shorting my wiring as I'm receiving no indication of a problem other than the starter clicking and the engine stumbling under acceleration.

13Beast REW

Also the problem is apprently across the ON and IGN circuits since it creates enough load to stop the starter from being able to turn the flywheel with the necessary force and prevents the engine from accelerating as it should. I'm looking through the wiring diagrams trying to figure out what systems would draw that kind of current just from the ignition being set to on, apprently it shouldn't be but very obviously... it is.

13Beast REW

I've also had the dash removed before but have been able to start the car since then. Also have spliced into the radio harness recently but again, I've been able to start the car since then. I've been looking over those circuits in the last few minutes trying to find something related around there. Only thing under the hood that I've messed with is the MAP sensor and even then its only really been the vacuum hose that I've been moving back and forth between the factory ECU and the aftermarket.

13Beast REW

This may or may not help...

I know the engine should trun over regardless of wether the ecu is connected or not (I know because I've done it and the circuits are completely separate from each other), so I disconnected the engine harness, pulled the connectors through the firewall and had them hanging over the side of the passenger fender. Basically, I negated that entire circuit from the issue.

Thats the main circuit I've been messing with as I've been messing around with different ECUs. Basically what I've decided is I'll just be removing circuits from the car one by one until I'm able to to turn the car over. I'm not so sure this will help though since if the problem is a wire shorting to ground rather than into another circuit this won't help me. Well... maybe if I disconnect from the ground side of the circuit it will still work.

I'd really rather not do this but unless someone has a better idea, I'm stumped.

13Beast REW

Fixed the problem. Turned out to be a lower engine grounding issue.

After my previous post, I pulled all fuses and relays not relating to the starting system and was still having the problem. That didn't tell me very much seeing how the fuses and relays are on the positive side of the FD circuitry. That would be a good test in terms of two circuits intersecting each other before the circuits ground but I had deep thoughts of a grounding issue from the get go. In my thoughts though it would have been another circuit grounding my starter circuit before the current reached the starter.

The way I verified the issue was first testing my old starter outside the car which tested fine. Hooked jumper cables up to the battery, negative cable to the body of the starter where the bolts go through, and positive ran to the bolt the starter cable bolts onto (B). Then I used a 10 AWG wire to jump the tab this ignition switch cable connects to on the starter (S). The old starter operated just fine.

Did the same test on the new starter... worked fine also.

Started thinking about engine grounds. Tested voltage to the engine ground going from the UIM to the firewall and it showed the battery voltage (slight loss of about .2 volts). When I measured the voltage to the new starter while it was installed there was a .4 volt loss so I wanted the test the grounding at the top of the engine.

I tried testing the old starter again but this time by (after disconnecting the positive battery cable), resting the body of the starter (where the bolts go through) against the upper intake manifold. I pulled the starter cable up to the top of the engine and wired it up like it would be if it was installed. A second person held the starter firmly against the UIM while I turned the ignition key... operated as normal.

After that I wanted to see how testing the starter outside of the car with it grounded to the lower region of the engine would go. Disconnected the starter cable and ran it back down under the engine. Wired the starter back up as though it was installed but now it just hung down from the engine (car was jack up atleast 12 inches). Connected the starter to the engine using the jumper cable. One engine on the bolt area of the starter, the other clamped on to the hole in the transmission bell housing where the starter would ususally go in to make contact with the flywheel. Positive voltage was provided by the regular battery cable. Turned the key... starter clicked and studdered trying to turn without the resistance of the engine just like it did when installed.

That told me the lower half of the engine did not have good grounding. I took a stretch of 10 AWG and crimped a loop butt connector on one end with a loop large enough to fit over the upper starter bolt. I then installed the starter on the engine as it would normally be and ran the bolt through the loop butt connector then through the starter, torqued it down then torqued down the other starter bolt. I ran the length of wire back up along the starter cable, zip tying it to the starter cable along the way, until I reached the negative battery cable. Cut the wire with about 6 inches of slack in it, and place a smaller loop butt connector on that end that would fit across the battery cable bolt. Replaced the battery cables and tightened them down. Replace all the fuses and relays. Turned the key... started right up and idled like new.

For those that could never understand when people talk about running new ground wires, thats how you do it.

So basically it was a grounding issue which makes sense in both cases of problems I was having. In terms of starting, the current build up was too large to make it across the remaining engine grounds and the current would basically stop flowing until enough electricity could cross the ground that was intact for more electricity to flow. Or, which ever ground went bad (which I haven't found and removed yet) could have been burned out enough to cause intermitant connections or was only connecting to the engine or chassis by arcing. That would make electricity build up along the engine until there was enough to jump the space between the engine and ground wire light a lightening bolt. That would discharge the electrical current and allow the starter to turn for an instant until enough current discharged until where there wasn't enough left to power the starter solenoid and motor. The starter would reset without voltage and then the cycle would start again.

In terms of the engine running, the same thing would happen this time it would likely be the grounding of the coils/spark plugs or possibley (and maybe more likely since the biggest problem occurred when boosting) the turbo actuators that push the voltage up too high for the remaining ground to handle and cause arcing or current flow problems through the faulty ground.

So there is the cause, solution, and justification for this problem so if any one has similar issues you basically have a path to follow to find your solution which may or may not be this. Always be careful when messing with electricity, wear rubber gloves or atleast laytex, use wire of a high enough gauge to carry the current you're trying to make a path for and if at any point you can smell fuel... FIX THAT PROBLEM FIRST!