lbs_ft

I own a 1990 S13 Coupe that the had a 1993 KA24DE swapped in by a previous owner. I blew that motor, so I recently finished swapping in a 1996 KA24DE, and it started yesterday with no issues. I drove it around the block, not a problem, but I noticed that my radio wasn't working.

I pulled it out and began to check and replace all the connections, some of which bypass the radio plug and tap directly into the car's wiring harness, namely the ignition and ground wires. I had the key turned to ACC (fucking stupid, I know) which I fiddled with the radio so I would know as soon as I had it right, and it ended up being a loose ground connection, but I'm worried that I might have touched the ground and ignition wires on the harness together.

I got it all back together, radio works fine, then I turn the key, and the car cranks and cranks and cranks but won't catch. I pull a spark plug to see if its sparking. Nope. I pull the dizzy-to-coil wire. No spark.

I fiddle with the battery leads, and eventually when I try to turn the car over, the EGM relay begins to click rapidly. I replace it. No more clicking, but the car still won't catch.

So now I think I'm fucked. There were no sparks, no smoke, no smell of burning electronics, but I'm terrified that I might have fried my ECU by leaving the key on ACC (stupidstupidstupid).

Anybody have any ideas? I'm in crisis mode now...

lbs_ft

Okay, I checked the grounds to the engine, and they're all good.

I used a meter to measure the power to the coil, and both the plugs are receiving around 12 volts when the key is on accessory, so power is getting to the coil. I also noticed that there was a fork-style connector on the base of the coil that wasn't connected to the wiring harness connector.

Does this sound right? Should there be power getting to the coil at all times? Should I just have to replace the coil? Or is the ECU still damaged?

lbs_ft

I need to borrow a early S13 KA24DE ignition coil and ECU. Anybody willing to lemme yank one out of your car just so I can identify my problem? I'll buy ya lunch

hottscennessey

I'm sure you did, but I figured I'd ask.. did you check all fuses and fusible links?

Once you double check that, when you put the key in the on position can you hear the fuel pump prime?

lbs_ft

Fuses are all good, fuel pump primes and you can hear it pressurize the rail.

I've got 12 volts going to the Ignition Coil, nothing coming out, so I'm ordering a replacement now. I hope that's all it is.

lbs_ft

I set the ECU into diagnostic mode today, and the it cooperated with the light blinking and all, which I guess rules out a fried ECU.

After cranking the car and setting the key to ON, but without the engine running, the ECU blinks and reads 11 (Crank Angle Sensor Circuit), 21 (Ignition Signal Circuit), and 34 (Detonation Sensor Circuit).

Any ideas?

hottscennessey

Code 34 is going to be from your disconnected knock sensor in your last thread

I'm curious about code 21, I'd like to see if it comes back after you re-set your ECU, or if it was just caused by the radio incident.

Unfortunately, you might need to borrow someone's working distributor in order to test for the code 11, there is always the possibility the circuit for the CAS is fried in the ECU. I see this a lot when I repair Nissan ECU's, as there is no protection when the ECU has a transistor "open" and there is a short causing 12 volts to enter that circuit. If the code 11 goes away with a different distributor, replace it. If not, you likely have a component burnt internally in the ECU (this could also be the case for code 21).

lbs_ft

Today I'm yanking the ECU apart to look for a burned motherboard. I reset it and those same 3 codes reappear. I replaced the knock sensor yesterday, and I can guarantee its working fine and all my connections are good. I don't know about the other codes, but I have an S13 KA24DE distributor, so the coil is seperated from the distributor by a wire, not contained within. I know that power is getting to the coil, 12 volts, but nothing is coming out.

I don't have anyone to swap parts with, whether it be an ECU, coil, distributor, whatever.

I'm thinking I might've fried something in the ECU, but there's no way to know for sure until I pull it after work.

Do you know of any way to check the resistance in the coil?

hottscennessey

If the harness connectors match up, you could always test for the CAS code with the S13 distributor, just leave the coil disconnected. Both S13 and S14 CAS's have the same number of slots in the wheel.

to check coil:

lbs_ft

What's a CAS code? haha and what do you mean about slots in the wheel?

I'll test the resistance for the coil asap