2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

May finally have found my problem! Leading coil busted???

Thread Tools
 
Search this Thread
 
Old Jun 27, 2004 | 02:26 PM
  #1  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
May finally have found my problem! Leading coil busted???

Alright, i was just out timing my car (this is the first time ive ever timed it with a timer that has a built in tachometer. For some reason it reads the rpm's at x4 though... if it were idling at 800 it would read 3200) And on the L-1 terminal the rpm's were jumping from 3200 all the way down to about 500 or so rpms, which makes no sense because the idle was staying about the same (although very rough like usuall).

When i put the timing light up to my hand, whenever i would have a short hesitation in my idle, the timing light would pause for a second, meaning that its not firing intermitantly for some of the time i guess. Whenever my engine would stutter so would my timing light.

When i put it on L-2 and T-1 it didnt do this... what could it be???
Reply
Old Jun 27, 2004 | 02:32 PM
  #2  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
First off, if L2 is firing, so must L1 (they share the same coil)

Secondly, the timing light doesn't know it's on a rotary engine where the leading system fires 6 (both plugs)times per e-shaft revolution, that's probably why you're getting the funky numbers...

Last edited by WAYNE88N/A; Jun 27, 2004 at 02:37 PM.
Reply
Old Jun 27, 2004 | 03:22 PM
  #3  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
I know that the L-1 and L-2 are on the same coil, and both are firing.

The difference is that the L-1 tach reading on the timing light was jumping from 500-3200 and all in between, while the tach reading on the L-2 was pretty much even, staying around 2400-2600. The engine idle would remain constant the whole time....
Reply
Old Jun 27, 2004 | 03:29 PM
  #4  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
Bad plug wire then, or shorted plug (or threads so dirty that it has a weak ground)...
Reply
Old Jun 27, 2004 | 03:44 PM
  #5  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
What do you think is shorted? I spark plug or a connector plug to my leading coil?
Reply
Old Jun 27, 2004 | 03:50 PM
  #6  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
OK, do this- swap the leading plug wires between L1 & L2, and try the timing light thing again- if the L1 circuit is still "jumpy", then it's not the plug wire...If the "jumpiness" now goes to the L2 side, it is...
Reply
Old Jun 27, 2004 | 04:05 PM
  #7  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
The plug threads are clean, so i know they are getting good ground with the block. Ill try the plug wire swap here in a minute, if that doesnt work what else could it be? Also the plug wires a pretty much brand new, only a few months old so my guess is its something else.

Is the coil itself grounded? If so where, and could that be a possibility?

It seemed like it would be a coil related problem because of the fact that when the engine would stutter, so would the timing light...
Reply
Old Jun 27, 2004 | 05:57 PM
  #8  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
The coil (igniter body) is grounded to the chassis by design, with just the hardware. If you like, you can remove the coil assy, clean off some paint down to bare metal in a spot near one of the studs, and "bolt" her back down to see if that helps. The only problem I see with this theory is that your L2 side is working beautifully, though, so I wouldn't suspect a bad ground...How does your L1 plug look? Is it wet, or something goofy like that? Also take the L1 plug wire off of the coil assy "receptacle" and take a look down in there, sometimes they can corrode on the electrode boss...
Reply
Old Jun 27, 2004 | 07:06 PM
  #9  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
Alright, some crazy stuff has just been happening. I switched the plug wires like you said, and then tried to start her up and she flooded. So i pulled the fuse etc. and got her started (no tach working like usual when she floods). I go and check the leading wires and.... nothing. No reading at all, 0 rpm on the tach, and no light. Same with the secondaries, and she was running, although like ****.

I turned her off and started her back up (tach now working) and i get barely any signal from the L-1 spark wire (like a blip every second, very irratically) and NO signal from the L-2 wire (which used to be the L-1 wire). Secondaries now firing fine, perfectly without hesitation.....

Then i turn it off, check the timing light, change the leading spark plug wires back, and turn the car back on. Now im getting the original thing that was happening, stutering blips on the L-1 wire with the irratic rpm's, the L-2 is fine, but now the SECONDARIES are giving me barely any signal.... i am SO DAMN CONFUSED!

Can anyone help me figure this out?? Any ideas will be much apreciated
Reply
Old Jun 27, 2004 | 08:10 PM
  #10  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
Are you sure you don't have a fuel injection problem (flooding), or a compression problem (flooding), instead of an ignition problem (or a timing light that gets totally freaked out by a rotary's ignition system)???
Reply
Old Jun 27, 2004 | 08:42 PM
  #11  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
Compression im not sure about. I was going to test it today but i dont have the right sized threading to thread into my spark plug holes.

As far as flooding the car rarely floods. It is a little more often now because i need to replace my plugs (the car fouls them pretty quick due to the richness) but that all. I dont have a constant flooding problem, i think a crappy starter is also adding to the mix by not spinning fast enough for the engine to catch. I need a new starter, this ones on its way out.

I HOPE its not a compression problem... i wouldnt like that very much
Reply
Old Jun 27, 2004 | 08:49 PM
  #12  
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Mar 2004
Posts: 485
Likes: 0
From: AZ/CA
It could be the timing light too. Its not a crappy one though, its a good quality digital snap-on if i remember correctly.

How would i go about checking my fuel injection system for flooding? Like leaky injectors for instance, is there a check for that?
Reply
Old Jun 27, 2004 | 09:22 PM
  #13  
WAYNE88N/A's Avatar
Lives on the Forum
Tenured Member 05 Years
 
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
What flashed through my head was: You're splashing so much fuel around in there (injector problem, something else?) that your plugs are getting coated and stomping out the spark every now & then, hence the timing light strobing erratically. If all else fails, pull the plugs, and hook everything back up to the plug wires, then crank her with the plugs close to ground so they'll spark. See if you get intermittent strobing then. If you don't, your ignition system's good, and something else is wrong...
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
alphawolff
1st Generation Specific (1979-1985)
17
Nov 17, 2015 05:57 PM
lt1_rx7
Blue Ridge Rotary Run
46
Oct 9, 2015 03:11 PM
Marty RE
New Member RX-7 Technical
0
Aug 17, 2015 09:36 AM
Wolf_
Single Turbo RX-7's
3
Aug 11, 2015 04:23 PM




All times are GMT -5. The time now is 02:37 PM.