Fc rx7 won't start
 

First of all, it's not a brand new swap and it has been running well for me for the past year until a few weeks ago.

Car cranks over just fine (IE - starter engages, motor turns, etc.) My problem is no spark.

At first...it would intermittently start. Would have to turn the key 3-5 times sometimes before it eventually started. Other times, it would start first try. Then one day while driving, it just started dying. Would push clutch in, rev it, would come back alive.

Currently, it will not start at all. When trying to start it, I get no RPM reading on my gauge, which points to a CKP issue, but as you can see below, I have gone over all of that.

What I've checked so far:
new NGK tr55 plugs and all my plug wires have ~30ohms
Get ground from block to shock tower and ground from negative battery terminal to shock tower (everything is grounded)
All my fuses are good
Blue and red pins 1 and 40 are grounded.
Blue pins 20 and 57 have 12v constant
Blue pin 19 has 12v ignition
CKP Pins (Blue 2, 12, 21) have continuity between CKP connector and PCM connector
New CKP
Swapped my PCM into a buddies Transam, started right up first try
Coil pack harness pink wire has 12v, black wire is grounded. Individual coil packs also have 12v and ground, yet i'd assume they just arent getting the signal to fire.
I can hear the fuel pump and regulator gauge right before fuel rail shows ~60psi

Currently have the intake pulled to check MAP and Cam sensor, yet i don't think they contribute to spark issues.

Another weird thing is that my Kenwood radio receiver wont turn on. This happened as my car wouldn't start. No coincidence here. My Jeep also has a Kenwood deck, so i stuck the RX7 deck into the jeep and it powers up, so the receiver isn't dead. It only needs 2 wires, possibly 3 to turn on. It has the 12v constant to keep radio memory, ground, and ignition 12v. I've probed them all and they all check out. So I'm not sure as to why the Kenwood deck won't turn on in the Rx7 but will in the Jeep.

have you tried changing the sparkplugs?

yes...this issue is a little deeper than spark plugs. Will edit "checked list"

Someone wanna help me out and go unplug their TPS and see if car starts or has RPM reading while trying to start?

I have this: http://www.jegs.com/p/Caspers-Electr...57621/10002/-1 All the reviews I read about it says it works and voltage is boosted a good 2v under WOT, thus headlights getting brighter. Mine still got dim, along with the radio cutting off at WOT. So if this box has gone bad, thus preventing a TPS signal from getting through...

I would test it myself and remove it and try to start the car, but my intake mani and starter are off.

Anyone...?

Have you checked the regulator? Are you still getting 60psi when cranking? Just because you hear the pump motor doesn't mean you are getting fuel to the injectors. It will crank all day, but if it's not getting fuel, it's not going to start.

While cranking, will it start if you spray an accelerant in the TB? If so, you have a fuel problem.

Take an LED and hook it up to each injector while you crank, will tell you if they are getting a signal from the pcm (which they should because it worked on your buddies). If not, you have a wiring issue because the pcm appears to be good.

Just went through all this with my buddies 1JZ swapped 280z. A shop told him it was his Bosch 044. He replaced it, nothing. Then I went through and pretty much ruled out every possibility until I found out that his stock regulator was bad and sending ALL the fuel back to the tank.

I unplugged my TPS and it started right up, too quick to see if I had a tach signal... honestly I'm not sure if I ever noticed my tach when cranking before.

I agree it sounds like a fuel pressure issue, but if you're sure you're not getting SPARK then that just would't make sense.

Rereading your first post, sounds like a short somewhere... one that's giving you an sporadic issue w/ your ECU... and everything else.

Just noticed you do have a gauge so nevermind. What kind of FPR are you running?

Have you checked for codes yet? Didn't see anything about that above.

Since it's a swap, I would lean towards a loose/faulty wire. BUT, you need to make sure you're getting both fuel AND spark.

Like I said, I have no spark. The coils have power and ground, just no signal to fire as indicated by no RPM reading...yet the CKP sensor tested good.

Try checking your MAF. I had this issue on my C5.

Are there any trouble codes? CEL?

I don't have a MAF, SD tuned.

No codes when it was running intermittently, but i cant sync to reader when car isnt running. Has power and all, just won't currently sync.

Do you have access to any kind of datalogging equipment? when you crank the engine are you seeing any read out on your tach, so it would lead me to think that your pcm isnt powering up at all.

Be sure and check the power and ground to the pcm. Here are the pinouts for the power and ground.

Grounds.
Pin 1 and 40 on both connectors. Should be black with white tracer.

Power.
Blue 19 should be pink ignition power. 75 could also have an ignition source if you are utilizing the vortec pinouts.

Blue 20 and 57 will both be battery power, will be an orange wire.

Refer to checked list

Duh! Im bad about skimming sometimes..:buttkick:

Ill think on this one, devil dog. Ill report back with some more ideas tomorrow.

IF your buddy doesn't mind the risk, run his ECU for a few drive cycles... if it started up just fine w/ it maybe that's the problem... or a short somewhere that caused the problem in your ECU (why I think it would be a risk to use a buddies).

lol thanks...especially think about this part (coincidence, I don't think so):
Another weird thing is that my Kenwood radio receiver wont turn on. This happened as my car wouldn't start. No coincidence here. My Jeep also has a Kenwood deck, so i stuck the RX7 deck into the jeep and it powers up, so the receiver isn't dead. It only needs 2 wires, possibly 3 to turn on. It has the 12v constant to keep radio memory, ground, and ignition 12v. I've probed them all and they all check out. So I'm not sure as to why the Kenwood deck won't turn on in the Rx7 but will in the Jeep.



I don't see what his PCM will do for my car if my PCM started his car. That eliminated any PCM issues. So if I have a wiring issue in my car, that would also affect his PCM...

Okay, read what you wrote backwards. Sorry seems like half this thread is people not reading your first post closely enough.

When the car first started doing this, would it run good after it would finally start? Check voltage while the engine is cranking. This sure seems like a wiring issue to me.

Pretty much :read:

When it first started doing the no start intermittently, it would run like a champ after it did start. My last drive or 2 though I would just be driving and it would cut out. If I pushed the clutch in and gave it a few revs it would come back to life. That is, until the final time i did it, when thankfully I was able to coast into a parking spot at my ex's apartment. From there, it got towed to my place.

Yes, I realize this is a wiring issue, but according to every troubleshooting guide MY CAR SHOULD RUN!!! So if anyone has any bright ideas...

Have you done this yet?? If you don't have an LED, there are "noid lights" that plug right in to the injector connectors. I've seen 'em at Autozone/NAPA/etc. for like $7 to $10 or so. That should let you confirm the 'no spark signal' diagnosis.

ALSO - have you unplugged, & then reconnected the coil harness connections? Not the connections to each coil, but the connection from the wiring harness to each bank of coil signal leads.

To ME, it absolutely sounds like there's a wire/connection that's either been getting increasingly LOOSE, or increasingly CORRODED. It's unfortunate that it's at the point to where it won't start at all, since if still ran, I'd suggest that you grab a portion of the engine harness while it's running, wiggle it a little bit & see if the problem recurs - but maybe you can do the same thing in reverse. Have someone crank the engine, & grab a suspect portion of the harness, wiggle it gently & see if you can get it to fire. If so, that will PROBABLY help you narrow down where to look. (I would think...)

Final thought - one of the earliest jobs I had in my life was doing military/space electronic assembly, & I was fortunate enough to work with a guy who was a really good troubleshooter. I told him how impressed I was at some of the stuff he'd been able to fix, & he told me something that stuck with me through the years since then - he said "Y'know, about 80% of the time, the best troubleshooting tool you have is your EYES..."

Don't know for sure if this will help you solve the problem, but I sure hope that it's helpful... Good luck.