Extreme electromagnetic interference from 2 sets of plug wires, please read!

[MarkAngelo05]

Hi,

I am experiencing a crazy amount of EMI from the last 2 sets of BRAND NEW PLUG WIRES THAT I TRIED. One set was the Ebay set of 10.5mm 7core wires, then the other set is accel thundersport 300+ wires! This is the problem,

These wires cause so much EMI that it messes with the values that my ECU sees. My logger goes crazy around 4k rpms and displays -64 timing, 0.00 airflow, and rpms just bounce around!

I put back my stock plug wires and I can magically log correctly and outputs values regularly, my car seems to run better, but at the top end it kind of bogs because my stock wires are nearly shot...

So, what is going on here? 2 sets of defective plug wires in a row??? Has anybody else experienced this before??? Thank you!

Mark

 

[luv2rallye]

This may help: http://www.dsmtuners.com/forums/showthread.php?t=147493 post 3.

 

[1gcrazy]

I HATE accel. I would have tried MSD or Champion. Or hell go back to stock....nothin wrong with OEM

 

[MarkAngelo05]

Thanks for the replies, I went to that page and I have seen that before, that Is why I went with accel.. it was 2nd on the list... with MSD Being first... I do not know what's up with these wires.. I bought them brand new... Oh! I did look around and there was a link to an article that talked about dyno testing different ignition systems and wires.. and found that msd wires caused EMI that made their engine management system misinterperet some signals... i'm calling accel/mrgasket first thing in the morning!


Mark

 

[adiffrentcity]

Are the wires touching each other? Like laying on top of each other? Ive seen problems with arc-over (admittedly in older v8s) where no wire separators were used, or worse some jerk was using wire ties (really!). Also if you push too hard when installing and kink the wires you can kill em easy. You might try testing your coils too. Iknow this is common sense stuff just trying to help.

 

[toybreaker]

That is pretty weird...

I'm wondering if there's something else contributing to the issue.

You're not running some kind of super elleventeen electrode spark plug, or a very large gap on the factory ngk's are you? An increase in secondary resistance will lead to an increase in the voltage required to ionize the air in the spark plug gap. This will increase the magnetic field generated by the wires by a corresponding amount. This can create some interesting side effects, such as you're describing.

A glaze on the plugs can do the same thing. Prolonged idling/slight amount of blow by/slightly incorrect mix/use of fuel cleaners, and etc, can lead to deposits on the plugs. If you then boost it up, you can melt those deposits into a insulating glaze that will substantially increase the voltage required to fire the plug.

Have you changed anything in your wiring harness/routing/added any tuning devices recently? Are the plug wires routed following the same routing as stock?

Other than that, I'm kind of at a loss to explain it. If stock wires cure it, a fresh set of ngk wires may be the best way to go. I'd fire in a fresh set of ngk plugs, gapped at .028", and call it done.

It may be the emi is only interfering with the logger, and not the car.

For what it's worth, I've been running the same thundersport wires for five years, (over 75k miles,) on my 1g, without any issues. (scored them at the boneyard for free )

Please, pm me your address/info, and I will sacrifice sneaky: ) a few days on a beach..I mean, come out to your location and troubleshoot this issue for you.

 

[MarkAngelo05]

Hi, thanks for your input... I had already put my stock ones back in and the car runs fine, and no sign of EMI specially for the ecu and data logs. I believe its the wire set... I am sending them back to accel. thanks!

Mark

 

[MarkAngelo05]

Howzit goin toybreaker!

Thanks for the steps... I have checked everything, even if I just leave the stock set hanging around touching eachother, it does not affect my car at all. but these accels are a different story, they make my car run like crap on the high end and cause my logger to read very awkward stuff. if you ever come to hawaii man, i'll be happy to show you around!! its an alright place man... its not all that, but if you're just a tourist or visiting, its GREAT! but to live in.... expensive and i feel stuck on an island with a load of pot holes...

mark

 

[Rice Over Wheat]

You think that's bad? I put a brand new set of Magnecors on 5 days ago and was getting random misfires. Then on the highway back from work my car start misfiring so bad that I could hardly limp off into a parking lot at 5 mph. Pop the hood and there's a popping sound around the wires as the engine runs and I kept getting serious static shocks from any metal in or around my car until I shut it off.

I since put my 3 yr old NGK wires back in and the car runs great again. Part of it might be from the shit poor design of Magnecors where they don't have a 90* bend like other wires. Instead you have to bend them to an angle with the boot, making them easy to pop out and tilt off center from the tension in the wire. What a rip off those things were.

 

[toybreaker]

I've been seeing more and more problems with plug wires on these cars.

I've had pretty good luck with the factory wires on all but the most modified cars.

Some care during the service/replacement of the plugs and wires will pay great divedends in the longetivity of whatever wire you choose.

Always twist the boot back and forth to break the boots' grasp on the plug porcelien, before trying to remove the wire. If you just try and yoke them off, you'll probably damage the wire internally, or even pull the end off.

Don't bend the wire sharply anywhere along it's length. Once they've been in service and taken a set, it's really easy to damage them by bending them too sharply during maintainence.

The actual conductor on many aftermarket wires is an incredibally small wire, wound spirally around a core. Bending/kinking the plug wire sharply can break the spiral wire, resulting in significantly increased resistance.

The actual conductor in the factory wires is (effectively) a string that has been coated with carbon. After they've been in service, they kind of take a set. Bending the wire against it's natural set can break the carbon coating/kink the string, resulting in a little higher resistance in that spot. Add that up each time the wire is flexed hard, and you can see slowly increasing resistance, and the resulting misfire under load that makes you change the wires before their time.

When installing a fresh set of wires, a few minutes spent on the details will ensure a longer, more trouble free worklife.

Always, put some silicone di-electric grease on the inside of both rubber boots before installing the wires. (I usually just put a little on a small screwdriver and wipe it around inside the boot.) This will allow the wires to slide onto their terminals easier, and more completely. It will also allow you to get them back off within a few months when you're changing the spark plugs out. You can get the silicone di-electric grease in little packets at the chain stores, or tubes at Napa.

Also, on the thicker, aftermarket wires, be carefull how you you install them. They probably won't fit in the factory wire guides well. Do NOT force them to fit, as you will probably damage the conductor wire inside, at the very least you will damage the outer insulation. Many chain stores sell oversized separators, and these can be used to get a nice, clean routing.

I haven't had any luck either with the "fit's-all" boot design, like Rice Over Wheat just experienced. There's just no way to make them work well, tease: but they fit an alfa romeo just fine )

Be especially carefull around the fuel pressure regulator/fuel rail on the 1g's. I've seen a couple cars where the wires are just run down thru the gap, and not restrained/isolated from all the sharp edges, (like the spring clamps on the fpr hoses.) I really like the rubber block that came stock in this location. If you can re-use it, I strongly recommend that you do so. At the very least, you can put some plastic split wire loom over the wires, to keep from slicing the soft silicone open on all the sharp stuff in that area.

If you do a nice install and routing job, and put some care into removing and installing them during service work, a good set of wires will give excellent service.

 

[MarkAngelo05]

Thanks for your input! I sent them in to accel to get them diagnosed and hopefuly send me a new set. Also, I have noticed that all the aftermarket wires that i've tried that have caused me problems with EMI are significantly longer than the stock OEM replacements. Maybe that has added a factor in experiencing problems with EMI. I am usually very careful when installing or removing plug wires, as I know they can be very fragile. And yes, the use of Silicon Dielectric Grease is a must.. A couple times I didn't have that and my plug wires got damaged when removing them because they get stuck!

DOES ANYONE KNOW IF THE NGK BLUES ARE THE SAME LENGTH AS OEM REPLACEMENTS?? If so, then I'll probably go with those when all else fails.

THANKS!!

Mark Padilla

 

[MarkAngelo05]

HERE's an UPDATE, ACCEL was pretty quick! I got my wires on monday!! They shipped me a brand new set! So far so good, no problems with my logger and no stutter during acceleration. I also put in some new BPR7ES plugs gapped to .028

THE PLUGS I HAD IN THERE WERE FROM ROAD RACE ENGINEERING.. They were BP7ES plugs. what's the difference between the R and the non R plugs? also I ran these plugs for about 8k miles, and the gap was way off already.. originally gapped at .028, they ended up at around .034 specially the #4 cylinder was pretty huge...

Mark