Misfiring?
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I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
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From: Oceanside, CA / NW Indiana
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Joined: May 2006
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From: Ontario
Originally Posted by CoolGuy094' timestamp='1434719695' post='23653481
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Once you can identify which cylinder is the issue, then focus on that coil, injector, cable until the problem is solved.
if it's happening at 2K RPM isn't not spark blow out (unless the spark plug was in terrible shape and out of spec).
I'm wondering if a log file from the AEM will help at all, but I can't think of what light it might shed expect it's dumping fuel to compensate.
you could put the stock ECU and stock Injectors, stock O2 in and just don't go into boost and see what happens?
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No I don't have any buddies with S2's but I'll probably end up buying the coils. How do you ditch PnP cables for something better? And also you believe it's the cables being intermittently faulty even though it happens all the time but when I pull them at idle it changes the idle drastically? And if not cables you think coils? Thank you.
The PnP connectors are all typically made in China quality including the wires. All of the ones I've seen have had very poor quality wires, and the connector bodies aren't much better. I went through two sets where the connector pins were completely loose inside the connector body, sometimes resulting in the pin coming completely out of the connector body when attempting to install. One time I was having breakup issues at idle and just wiggling one of the PnP wires in the middle made it stop or start misfiring, hinting that it was the physical wire that was the issue, not the pins in the connector.
Eventually I got a set that worked fine for as long as I owned them, but I went through several sets to get there. Some will be fine, some will be terrible. Again, typical made in China quality.
Its cheap enough to just put a bottle of Techron fuel injector cleaner through your fuel system. The bottle says to dump it in with a full tank of gas, but I like to put a full bottle in when I'm around a quarter tank left and run it close to empty (which isn't exactly good for your fuel pump) but I feel like you get a higher concentration of the Techron passing through the system. If you find that its running slightly (or notably) better after the Techron, then maybe its your injectors in need of some cleaning.
You've been through a few tanks of gas while this has been happening, right? Couldn't just be bad gas or something simple like that right?
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Joined: Oct 2011
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From: dfw
so I had part throttle misfire a few years ago it was the pnp connectors. I soldered them in series with the stock connectors due to inspection purposes and it fixed my problem but to me it sounds like a coil pack get one and move it around to see if one is bad I carry a spare coil at all times. I also carry a spare diaphragm for my bov sense its shat the bed twice in 30k miles. good luck with it I also run iridum plugs I was getting rough idle cold and radio interference from the copper plugs just make sure your running the proper heat range.
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Joined: Sep 2014
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From: Oceanside, CA / NW Indiana
Originally Posted by RZA' timestamp='1434731732' post='23653700
[quote name='CoolGuy094' timestamp='1434719695' post='23653481']
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Once you can identify which cylinder is the issue, then focus on that coil, injector, cable until the problem is solved.
if it's happening at 2K RPM isn't not spark blow out (unless the spark plug was in terrible shape and out of spec).
I'm wondering if a log file from the AEM will help at all, but I can't think of what light it might shed expect it's dumping fuel to compensate.
you could put the stock ECU and stock Injectors, stock O2 in and just don't go into boost and see what happens?
[/quote]
What do you mean by removing spark I'm taking the rest out of the equation? And I dont have the stock ecu or injectors anymore.
Thread Starter
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Joined: Sep 2014
Posts: 95
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From: Oceanside, CA / NW Indiana
Originally Posted by RZA' timestamp='1434731732' post='23653700
No I don't have any buddies with S2's but I'll probably end up buying the coils. How do you ditch PnP cables for something better? And also you believe it's the cables being intermittently faulty even though it happens all the time but when I pull them at idle it changes the idle drastically? And if not cables you think coils? Thank you.
The PnP connectors are all typically made in China quality including the wires. All of the ones I've seen have had very poor quality wires, and the connector bodies aren't much better. I went through two sets where the connector pins were completely loose inside the connector body, sometimes resulting in the pin coming completely out of the connector body when attempting to install. One time I was having breakup issues at idle and just wiggling one of the PnP wires in the middle made it stop or start misfiring, hinting that it was the physical wire that was the issue, not the pins in the connector.
Eventually I got a set that worked fine for as long as I owned them, but I went through several sets to get there. Some will be fine, some will be terrible. Again, typical made in China quality.
Its cheap enough to just put a bottle of Techron fuel injector cleaner through your fuel system. The bottle says to dump it in with a full tank of gas, but I like to put a full bottle in when I'm around a quarter tank left and run it close to empty (which isn't exactly good for your fuel pump) but I feel like you get a higher concentration of the Techron passing through the system. If you find that its running slightly (or notably) better after the Techron, then maybe its your injectors in need of some cleaning.
You've been through a few tanks of gas while this has been happening, right? Couldn't just be bad gas or something simple like that right?
Joined: May 2006
Posts: 7,430
Likes: 2
From: Ontario
Originally Posted by iDomN8U' timestamp='1434734103' post='23653761
[quote name='RZA' timestamp='1434731732' post='23653700']
[quote name='CoolGuy094' timestamp='1434719695' post='23653481']
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
[quote name='CoolGuy094' timestamp='1434719695' post='23653481']
I would still consider the PnP cables to be suspect until the problem is proved to be something else...
Next thing I would try would be coil packs. Do you have any local friends with S2000's that would let you swap coil packs just to see if that's the problem? You'd hate to spend the $$$ on a new set of coil packs and that not be the issue. Just remove his four coil packs, swap them onto your car, then test drive to see if it fixed the problem. If it did, then put your four old coil packs back on the car and just swap #1 coil pack out with one of your friend's to see if the problem is still gone. If so, then #1 coil pack was the issue. If not, then move #1 to #2 and repeat until you find the bad coil pack. Careful though, it could be more than one coil pack going bad at the same time. If replacing all of them fixes it but trying to replace one-at-a-time doesn't give you the same result, then you need to go ahead and replace all of them with new ones.
Another thing that could cause this would be dirty injectors. A customer of mine struggled with a random misfire for a long time. We tried swapping coil packs and plugs and all that jazz but narrowed it down to what I thought were dirty injectors. The problem would get better after a bottle or two of Techron injector cleaner, but would eventually come back. Finally he removed his injectors and had them professionally cleaned and flow tested and that fixed his problem for good.
Good luck; these are annoying problems to deal with.
Once you can identify which cylinder is the issue, then focus on that coil, injector, cable until the problem is solved.
if it's happening at 2K RPM isn't not spark blow out (unless the spark plug was in terrible shape and out of spec).
I'm wondering if a log file from the AEM will help at all, but I can't think of what light it might shed expect it's dumping fuel to compensate.
you could put the stock ECU and stock Injectors, stock O2 in and just don't go into boost and see what happens?
[/quote]
What do you mean by removing spark I'm taking the rest out of the equation? And I dont have the stock ecu or injectors anymore.
[/quote]
What I mean is that your ruling out which one cylinder is having the issue. The only things on that cylinder are Spark plug, Coil, Injector and Cable.
Example: Car is idling a little rough. You pull injector cable on cylinder one. Car idles the same. Cylinder one is the problem, whether it's the cable, coil, plug or injector.
This is only if it's happening at idle.
Since you're not having a idle issue, then this procedure doesn't apply.
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How long has that one tank of E85 been in your car? E85 is known to absorb moisture from the air in a short amount of time. It wouldn't surprise me if its just bad gas. Are you flex fuel or do you have to run straight E85?