So, today i put in my restrictor pill, and went for a little spin and everything felt good. I drove home and parked in my parents driveway. 30 minutes later, it starts up and runs like ****. after about 3 minutes of idling, it magically starts running fine. About halway to my home (bout 7 miles) it starts running like **** again. It'll idle low but won't stall out. It also sounds like my spark plugs aren't firing or something. You would just have to hear it...

The metallic noise is my split air hose banging the exhaust manifold.

Only ecu code is #17.

S5 Vert having a hard time running - YouTube

 

I just did a rather unique test...

I thought to myself (Hmmm, it sounds like I am only running on Trailing spark, and my remote start tach wire is attached to the Leading coil!".

So I remote start it, and what do you know, the remote start can't see tach, so it keeps spinning the starter even though the engine is running. If it had a tach signal, it would know to shut the starter down.

Looks like i am already narrowing this down.

 

Went back outside, unplugged the leading coil and it starts and runs the same.

So what now? Is it the Leading coil, the wiring between the leading coil and ECU, or the ECU itself.

What puzzles me is that it ran like ****, started running fine, then started running like **** again.

So basically I am at the leading coil, unplugged it, and the car runs just as it did before. I am not sure where to start. I'd be shocked if both leading spark plugs wore out at the same time. I guess I should pull them and see? What should I do? I also have brand new NGK wires, so that shouldnt be the issue.

 

i'd pull the plugs, they are probably ok, but you start simple. check the wires too, again they are probably ok, but you have them off...

at the coil the black/yellow wire, should have 12V with the key on. also check the pins, one of my cars the pin backed out....

if that all looks ok, toss a coil at it (you have a pile of those right?)

 

I don't unfortunately have a coil to throw at it, or that is what i would have done once i noticed I had no leading spark. If it IS the coil, I might hit you up for buying one if it is reasonable. My multimeter is at the shop...but I have been drinking so no driving to the shop to get it. I was just so ******* mad that the car started having problems I borrowed the wifes car to get some beer before I started messing with it. Wish I would have nagged the multimeter.

I am uploading a video right now...

 

Video...

S5 RX7 Leading coil failure. - YouTube

 

And the G/Y wire at the leading coil should alternate in voltage from 0 to 5 volts w/key to on and the Main Pulley rotated (rotating the alternator pulley will turn the other pulley).

 

I just started it up and it is running fine now.

I pulled a leading plug wire to see if it was firing and it did, and now the car started running normal. The hell?

 

Hey you fixed it! Maybe do a little more troubleshooting before creating a thread next time...

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LoL...

What are you a

 

I didnt do anything...I was trying to troubleshoot and it suddenly comes back to life.

I seriously doubt this is the last time I see this problem.

 

Sounds like trick wires to me...

 

And now it's back...

Went and started it up and the leading coil stopped working.

 

You need to test the G/Y wire.

 

this definatly sounds like your running on one rotor.

On both coils, there are plastic caps, under the caps are terminals with 8mm nuts on them, MAKE SURE THEY ARE CLEAN AND TIGHT.... my buddies got coroded and then problems like this showed up,

also check for a leaking injector if you find that the coils are fine

One rotor >

 

^ that engine was running on one rotor, b.c we stabbed the CAS one tooth off. but just so you know what a one rotor rotary sounds like

Same vehicle after everything was fixed:

 

No, more of freaking out.

So, yesterday, it started running like **** and then started running right again. The, it ran like **** again. I am going to jerk the leading plugs today. I took the day off work, so I can't really go to work and get my multimeter.

 

So this is what I have noticed so far...

I checked the leads for the trailing coil (under the little cap) and they are good. I started the engine and popped off one plug wire at a time off the coil and I got spark on both sides.

This where it gets weird. I started the car stone cold this morning and it ran fine. I let it warm up, then shut it down to let the engine heat soak a bit while I ran an errand (spark plugs for the 7) in my wifes car. Come back, start it up, and we are running on one rotor again. I let it cool down all the way, start it up and it's running fine again.

I am letting it cool off some because I keep burning my arm trying to get to my leading plugs to swap the new ones in. New plugs can't hurt, even if it isn't the problem. If I can get to it, I might try and unplug the coolant temp sensor and see if that may be faulty.

 

how old are the plug wires? wires will be more problematic when hot versus cold.

 

Less than a Month old.

I pulled the front leading plug and got 3 powerful pulses. I am working on the rear rotor now.

I just pulled the leading plug from the rear rotor and 3 strong pulses just like the front. Holy mother god that plug is WAY more worn than the leading on the front rotor. They where installed at the same time. ****, I am surprised that ran at all.

We may have found our problem. We'll see.

 

FYI, I had a loose injector plug that would cause my truck to intermittently run like crap. If you can get under the hood with the engine running look and listen closely for anything that seems out of the ordinary, hissing, clicking, loose connectors, etc. You can make a stethoscope out of vacuum line and a screw to listen to the injectors if you can get to them.

Good luck!

 

I just started it cold and it ran like ****. We have good compression, new leading plugs, we got spark (although I kept my old wires so I may swap them in).

Can't get to my primary injectors. Considering how rich the exhaust smells, I hope they are firing properly.

 

check all 4 plugs with a timing light to see if for any reason one is dropping out while the problem is going on.

the only other thing i could envision is a faulty primary injector or clip.

 

Alright. Would a Trailing plug problem cause something like that? I always thought trailing spark was to help with incomplete combustion but the leading did most of the work.

 

I don't have a timing light so I did it the old fashioned way by pulling the wires off and looking for spark.

What I noticed was, if I pulled the rear rotors leading spark off, it didn't seem to give a ****. I also pulled the leading wire for the front rotor and the engine definitely did not like that.

I am going to swap one of my old plug wires over and see what happens.



EDIT: Nope, swapped the wire and no dice. Is there a way I can trick the car into being under load so my secondaries will come on?
EDIT2: Noticed my ECU ground on the engine worked loose...tightened it back up and no dice.

.

 

if the engine stalled with no front rotor lead plug and did not notice with the rear rotor wire removed and compression is fine then the obvious issue is the rear rotor lead plug isn't firing or the rear primary injector is intermittently working.

pulling the spark plug wires can be a little misleading, there may be voltage passing through the wires which means the coil is firing but it doesn't mean the plug is firing. but if you replaced the plugs and it still persisted i would move on to the injector/clip as being the culprit.