Help, possible ecu problem (novel inside :/ )

[RustspecS13]

So two days ago my battery positive cable went bad, while I was driving. It started running rougher in high vacuum and high boost (well 5-10psi, stock no boost controller) and my radio kept randomly turning off for a second.

I pulled over to try to reset my boost gauge since it got stuck in the mode to set the warning level. I believe the over voltage from the battery positive coming off the battery did this. This is when I noticed the positive cable and tried to put it back on. The 10mm nut was tight but the clamp was still loose, so I put a wire between the clamp and battery to get home.

By then I know my alt is toast, and isn't charging any more, so I get a 99 quest alt from advance. Once I get the old one off, I notice the positive from my lower harness got so hot it cooked the wire crimped in the eyelet connector, and made the rubber brittle. And the nut that held it on looked like some one welded on its side. So great a S#*% tonn of power went through it.

But then after I button up the alt and cooling system (pulled the rad for a flush) its starts right up, like it has been doing for the last 1200 miles.

I let it idle to bleed the cooling system, and then while I'm topping it off it stalls. And doesn't start back up.

I ended up pulling the #1 plug, and i thought it was a little wet with fuel. So i let it dry and it started. So I kept it running and then went around the block. It died and hasn't started since.

Ive pulled all the coils and they spark against the valve cover. I hear a bunch of injectors clicking, but they might not all be opening or might not be opening in the right order.

My timing belt is still tight, and last week it dynod at 212WHP 200Wtq. So it should have enough compression to ast least run. I doubt there's a internal problem.

It also wont run on brake cleaner like it did before, when my injectors weren't getting power. Carl said it may be because the battery isn't charged enough, so I'm going to get it charged and go from there. But I'm at my wits end so if any one has a RB20DET-manual ecu I can borrow....

~Alex
Modified by RustspecS13 at 12:43 PM 6/14/2009

[RustspecS13]

Is the RB20 set up for batch firing the injectors at idle or start up? Because it sounds like I get two injector clicks but multiple injectors are firing at the same time.

If that's the case then I have spark and fuel. I still haven't charged my battery since it has 11.75v just sitting.

~Alex

[RustspecS13]

I jumped the car, and same thing. It turns over just doesn't fire. Its definitely spark related as I can smell fuel in the car and the exhaust reeks of it.

The thing that puzzles me is I get spark from all the coils when they are sitting on the valve cover.

What would cause a weak spark? Could the alt have fried my ignitor or just damaged it? Could my ecu be on its last legs?

Any ideas would help. But tomorrow after work i'll break out the voltmeter and try to track down my problem, and take my battery into work to charge it properly.

~Alex

[Carl H]

spark and fuel is full sequential, if they're all firing at once you have a fried ecu.

[Darius]

Could it possibly be a bad CAS??

[RustspecS13]

It does this with 3 CAS's, the one the engine came with which i broke, the one that replaced it, and a j30 one i got for $5 just to test stuff like this.

I remember reading one of my nissans (that could be a 90 max a 95 max, or sohc s13's) was batch fire at idle/possibly start up, and then went sequential after X rpm. Which was either 1800rpm or 2400 or so.

The thing that gets me though is the spark LOOKS fine. It fires individually as far as the spark goes. But the fuel injectors seems to be firing in odds and evens.

Im going to put on my old ignitor and see maybe if that does anything..

~Alex

[RustspecS13]

So it started today.

I fully slow charged the battery at work, which is an optima redtop. And the #1 coil pack and spark plug has been out since wednesday. Today I put in an old plug, and the #1 coil back in. I tried to start it and popped once or twice. I keep cranking probably 5-8 more tries and it keeps catching more and more.

Then it starts! ZOMG WTF BBQ!! but now if i rev in neutral it cuts out around 5k. In gear I cant get into boost or much boost.

Since the last time these things have changed in this order:

-Battery pos came off, blew alternator-put on quest 125a alt, jegs e-fans, fans used existing efan wiring-ran for 15-20 min, died, replaced plugs with 1mm gap z31-T plugs*-let sit since wednesday -fully charged battery, put in small gaped old plug in #1cyl

*the old plugs are z31-t plugs and had a tiny gap, it was around .022-.024 or .6-.7mm. It ran good and got 25mpg on one tank so IDK. The new plugs I sent to 1mm.

But now under some boost it misfires HORRIBLY. And in neutral the more gas i give it the lower it revs, once past about 4-5k.

So I'm going to gap all my new plugs to .7-.8 like the old plugs. Which I guess are still good. I might even run the coil pack positive feed directly to the battery with a relay and fuse.

~Alex

[RustspecS13]

I replaced the ignitor (again) and it runs perfectly. I went to picknpull today and they had 2 fresh j30s. I pulled both ignitors and the connectors so now I at least I have spares.

OH man its so nice to have my boost back! I cant believe I missed 2 drift events because of a stupid ignitor ><

~Alex