No spark on any plugs

[Ajax87]

None of my spark plugs are firing. I'm sure this could be caused by a number of things (igniter, coil packs). Can anyone give me an order of things to check, and how to do it.

[Hijacker]

I usually start with ignitor. The primary reason being that a bad ignitor or poor wiring can easily cause the coils not to fire. I also find it extremely rare for all 4 coil packs to fail, so I would look at wiring. There should be a ground behind the head that the coil packs ground to. Check to make sure that one is still grounded properly.

[Ajax87]

I have one ground hooked up behind the head but there's also another wire back there. It's like braided with a small black plug at the end and it's not hooked up to anything. It's coming off of the back driver side corner up top where sr20det is carved in

[Hijacker]

That's a grounding strap for the motor to the chassis. These cars run fine without those hooked up. Since your coils are grounded, I would inspect the ignitor to make sure it's wiring wasn't disturbed

[Ajax87]

Does the ignitor need to be grounded to the chassis. I never mounted the brackets and when I took my chip off to test it I noticed the back was metal so I'm not sure if you have to mount the bracket to the chassis to ground it.

[zachattack_5491]

Does the ignitor need to be grounded to the chassis. I never mounted the brackets and when I took my chip off to test it I noticed the back was metal so I'm not sure if you have to mount the bracket to the chassis to ground it.

I don't have mine grounded to anything. There's a wire for ground on the harness.

I would also be interested to know if it's supposed to be grounded, I wondered the same thing when I first saw the back.

[Hijacker]

It's grounded through the harness. The only time I've had to ground them separately is when I'm doing custom harnesses and the like.

Worst case scenario is that you have to cut out the ground for the ignitor and ground it out individually. However, I would check to see if your ignitor burned out first. If you have a friend in the area with an SR, borrow his ignitor.

[Blown240sx]

The coils require a ground still. The actual coil its self grounds through the bolt into the head and the black wire on the back of the motor is the a ground for the ignitor, Its good to have ground straps on the motor. Ive seen it cause running issues on some cars. Your motor mounts are an non conductive material. It might ground through the exhaust at some point but I put atleast 3 ground straps on my motors. It promotes good spark and the possibility of shorting due to lack of ground. There are several sensors and spots in the harness that use the motor ground and not a chassy ground.

[Ajax87]

I did the fsm ignitor test. It didn't have continuity, but I've heard of cases where that didn't seem to matter. Also the ignitor gets hot when the motor is cranked. I'm gonna check for power before and after the chip. I don't have any friends with one either. My buddy just has the block. If anyone is interested in selling one let me know.

[Hijacker]

The coils require a ground still. The actual coil its self grounds through the bolt into the head and the black wire on the back of the motor is the a ground for the ignitor, Its good to have ground straps on the motor. Ive seen it cause running issues on some cars. Your motor mounts are an non conductive material. It might ground through the exhaust at some point but I put atleast 3 ground straps on my motors. It promotes good spark and the possibility of shorting due to lack of ground. There are several sensors and spots in the harness that use the motor ground and not a chassy ground.

In my experience, the factory straps are worthless. You get a better ground with just the negative battery cable since it connects the motor the chassis.

The coils are grounded through a communal ground on the back of the head. There are three pins going into each pack. One is a shared 12v constant, the second is a circuit complete through the ignitor chip to the ECU, and the third is the shared ground connected to the back of the head. Look at EC-120 of the S14 FSM to see what I'm talking about. As far as I know, the packs don't ground through the bolt since my standard method of checking timing requires using a coil pack that isn't bolted in place.

[PyR0NiAk]

Bart! Explain this method of checking timing...

[Hijacker]

post625445.html

Boom.

[PyR0NiAk]

That's going to be an article later.

[Ajax87]

i got another chip today from the junkyard. popped it in and nothing changed. both chips get pretty hot just after a couple cranks, i would think this means its getting power. as far as faulty wiring being the culprit, what should i check. how can i be sure that power is going in and out of the ignitor. I also checked my coilpack harness for continuity and it was fine.

[zachattack_5491]

Mine gets hot after cranking also.

Download the s14 sr fsm and look at pages 124-127 of the EC section. I'd just post it here but it's way too long.

What junkyard did you get an sr ignitor from?? I thought the only other car that had an identical ignitor was a Suzuki Swift or something.

[Blown240sx]

Why not just entertain the idea of check the ground?

[Ajax87]

I'm not exactly sure what you mean by check the ground. It's bolted onto the firewall. Seems like a good connection to me. I have a multimeter but I'm not electrical savvy. I'm not sure how to test grounds and current flow at all. I know that's pretty sad but if I'm not honest I'm not gonna get descriptive responses. Outta respect for hijacker and all the knowledgable people on here I know this sites overwhelmed with noobs. But we all start somewhere.

[Blown240sx]

Are the grounds on the back of the head or on the firewall?

Turn your multimeter to continuity and probe at the coil for a ground and at the end where the ground bolts and see if there is continuity.

Also check to ensure the ignitor ground is grounded well.


Also you may want to ensure your CAS is working properly.

[Ajax87]

my coilpack ground is bolted to the firewall. hopefully thats the problem. as far as the ignitor, where does it ground.

[PyR0NiAk]

The wiring harness....

[Ajax87]

cut open the harness just to see the connections. In this pic, you can see that the four wires come together, but they all join to a wire of the same gauge, maybe that makes sense because only one at a time has flow?


same thing with the grounds. this wire is the one i have bolted to the back of the head


Then this wire divides into two wires then goes to the plug?


Is this how the harness comes from the factory? Also, my battery light inside the car wont go off.

[Ajax87]

it turns out i have two known good coil packs, and three known good wires. when i put a good coilpack on the cylinder closest to the firewall (cylinder 4?) i get no spark. im guessing my ignitor isnt firing that cylinder and i have 2 bad coilpacks. I checked the faq for parts compatibility so im guessing i cant grab any coil packs at a junkyard. if anyone has any for sale let me know.