No spark on number 1 rotor?
#1
Eats, Sleeps, Dreams Rotary
Thread Starter
No spark on number 1 rotor?
So my car is running on just the rear rotor despite the fact that it has fuel and a reasonable amount of compression. I get spark when I pull the wires and hold the plug against the engine.
But I took a slow-mo video of the video and it seems like I'm only getting one leading spark every two compressions (based on the sound of the engine).
Shouldn't the leading coil be firing twice as often as the trailing coils since it has a wasted spark?
I suspect I may not be getting any trailing spark on the #1 rotor but its kind of hard to test since the plug cord is so short.
But I took a slow-mo video of the video and it seems like I'm only getting one leading spark every two compressions (based on the sound of the engine).
Shouldn't the leading coil be firing twice as often as the trailing coils since it has a wasted spark?
I suspect I may not be getting any trailing spark on the #1 rotor but its kind of hard to test since the plug cord is so short.
#2
Eats, Sleeps, Dreams Rotary
Thread Starter
I am getting trailing spark and it seems to happen at about the same pace as the leading spark, which probably shouldn't be happening.
Last edited by Valkyrie; 04-17-16 at 07:13 PM.
#5
Eats, Sleeps, Dreams Rotary
Thread Starter
Which would explain why only one of the rotors is firing.
#7
Eats, Sleeps, Dreams Rotary
Thread Starter
Since the RX-7 uses a wasted spark on the leading plugs it should be firing twice as often as the trailing plugs, no? (six times per rotor rotation, or twice per shaft revolution).
Trending Topics
#8
Eats, Sleeps, Dreams Rotary
Thread Starter
I think the previous owner had the coils in the wrong place... or modified their location for some unknown purpose. The leading coil was in the middle when it should have been on the right (the coil rack and wiring is not the same as USDM FDs).
#10
Eats, Sleeps, Dreams Rotary
Thread Starter
#11
Senior Member
Join Date: May 2013
Location: Johannesburg, South Africa
Posts: 301
Likes: 0
Received 0 Likes
on
0 Posts
Thats not good, I wouldn't try start the car until you sort that out, check the pin out on the ecu and make sure the right wiring is going to the right coil.
#12
Senior Member
Join Date: May 2013
Location: Johannesburg, South Africa
Posts: 301
Likes: 0
Received 0 Likes
on
0 Posts
This link helped me out big time when I was trouble shooting my ignition.
https://www.rx7club.com/3rd-generati...iagram-964089/
https://www.rx7club.com/3rd-generati...iagram-964089/
#13
Eats, Sleeps, Dreams Rotary
Thread Starter
This link helped me out big time when I was trouble shooting my ignition.
https://www.rx7club.com/3rd-generati...iagram-964089/
https://www.rx7club.com/3rd-generati...iagram-964089/
#15
Eats, Sleeps, Dreams Rotary
Thread Starter
I just realized that besides the L and T2 coils being in the wrong place, the plugs were also backwards. That explains everything.
#16
Eats, Sleeps, Dreams Rotary
Thread Starter
Except the engine still won't rev (past about 3,500 with no load) and constantly floods and won't start again until I blowtorch the plugs.
What the hell.
I've got spark on L1 and L2, at least...
L2 gets fouled with black stuff after about five minutes of idling and the engine stops.
I'm still not sure that #1 is actual firing even though it's got fuel and spark.
What the hell.
I've got spark on L1 and L2, at least...
L2 gets fouled with black stuff after about five minutes of idling and the engine stops.
I'm still not sure that #1 is actual firing even though it's got fuel and spark.
#17
Senior Member
Join Date: May 2013
Location: Johannesburg, South Africa
Posts: 301
Likes: 0
Received 0 Likes
on
0 Posts
Except the engine still won't rev (past about 3,500 with no load) and constantly floods and won't start again until I blowtorch the plugs.
What the hell.
I've got spark on L1 and L2, at least...
L2 gets fouled with black stuff after about five minutes of idling and the engine stops.
I'm still not sure that #1 is actual firing even though it's got fuel and spark.
What the hell.
I've got spark on L1 and L2, at least...
L2 gets fouled with black stuff after about five minutes of idling and the engine stops.
I'm still not sure that #1 is actual firing even though it's got fuel and spark.
Could be a number of things, bad spark plugs, bad spark plug wires, injector sticking open due to build up, injector O rings damaged.
Last edited by RuffRx7; 04-19-16 at 09:00 AM.
#18
Eats, Sleeps, Dreams Rotary
Thread Starter
One of them has a tiny, tiny leak but its so slow I don't think it could possibly cause flooding. They're not stuck open... and they do fire.
Spark plugs are mostly new but have been fouled a few times and I have new ones on the way.
I actually changed the injectors to some supposedly good ones I borrowed (for test purposes).
The plug wires are also borrowed and they're out of spec but not broken (have new ones on the way).
I haven't done any mods... not really. But it has a single turbo. It hasn't run right since I got it running.
What could the o-rings do?
Spark plugs are mostly new but have been fouled a few times and I have new ones on the way.
I actually changed the injectors to some supposedly good ones I borrowed (for test purposes).
The plug wires are also borrowed and they're out of spec but not broken (have new ones on the way).
I haven't done any mods... not really. But it has a single turbo. It hasn't run right since I got it running.
What could the o-rings do?
#19
Senior Member
Join Date: May 2013
Location: Johannesburg, South Africa
Posts: 301
Likes: 0
Received 0 Likes
on
0 Posts
Well I think you need to fix your leaking injector, are the injectors standard or aftermarket with aftermarket fuel rails?
I would wait for all the right items to arrive and start again, it sounds like everything you have is not to spec and could be causing all your issues.
I would wait for all the right items to arrive and start again, it sounds like everything you have is not to spec and could be causing all your issues.
#20
Eats, Sleeps, Dreams Rotary
Thread Starter
Stock.
I wonder if all the black smoke and the carbon on my L2 plug is simply that its only running on one rotor, which happens to be pig rich?
I wonder if all the black smoke and the carbon on my L2 plug is simply that its only running on one rotor, which happens to be pig rich?
#21
Senior Member
Join Date: May 2013
Location: Johannesburg, South Africa
Posts: 301
Likes: 0
Received 0 Likes
on
0 Posts
I would get all your injectors cleaned and checked, get new o rings and injector hats while you wait for the plugs and wires to arrive, then you know everything is good to go and if you still getting flooding on the rear rotor, I would do a compression test to see what the compression is like.
#22
Eats, Sleeps, Dreams Rotary
Thread Starter
I would get all your injectors cleaned and checked, get new o rings and injector hats while you wait for the plugs and wires to arrive, then you know everything is good to go and if you still getting flooding on the rear rotor, I would do a compression test to see what the compression is like.
I tried to use my piston comp tester but the damn hose wouldn't go into the plug holes... hehe. I would guess the compression is low but not blown.
Thread
Thread Starter
Forum
Replies
Last Post
dburks10
3rd Generation Specific (1993-2002)
15
04-05-16 03:35 PM