Ive got some MSD plug wires and it seems like they are causing and issue with the spark. Has anyone ever heard of this? If so is there a way to correct it in the tune?

Thanks.

 

If the wires are causing issues with the spark, why not return the wires? Tuning to fix spark plug wires just doesn't feel right to me...

 

Well I bought them off a member here and they were not on the car when it was tuned. Im thinking that the lower resistance could be causing something with the timing that was not there when the car was tuned. Maybe Im crazy I dont know.

 

Check to see if you have them fully seated.

OR

You can pull them off and check their resistance. They should all measure around the same ohms

OR

You cracked the porcelain on one of the plugs during your "change".



But, no, plug wires will not affect your timing.


Elmer

 

How much resistance should they typically run? Im guessing if one has far more than another it would cause a problem going from the coil to the plug. I just put new plugs in so they should be good. Ill check the resistance and the seat and see what I come up with.

 

Measure it and write it down. Do that for all 8. If you have one that is reading crazy bad from the other 7, that's the culprit. You are looking for an anomaly from the rest. Resistance varies by wire type and brand.


Don't assume that any of the new plugs you have are not cracked. It's pretty easy to crack the top of the plug.


Elmer

 

I know a cracked plug can make your car run like @ss. I just went through that whole ball of wax about 3 weeks ago. I just get wierd things happening every now and then. I had a miss fire at about 5500rpm once and couldnt figure out whym Well I guess Im gonna have to buy a new ohm meter since my last one was stolen so I know WTF is goin on.

 

Its not arc-ing off the header is it? Anylight show under the hood when it is dark out?

 

Not sure Ill have to check. I dont typically open my hood while its running and dark out since I cant see in there. This is a good question though never though of that.

 

Aftermarket wires are a joke. We have seen all kinds of intermitant codes from MSD wires. I would just leave them stock since there is not really any good reason to replace them.

 

I have MSD wires and no issues with a dyno run. Friend with C5 also has MSD wires and his dyno run/tune went smooth also.
Tom Wong has mentioned that the MSD coils messed with his Mustang Dyno though..

 

No need to spend big bucks on a multimeter...$20.00 at your local Sears and fits in most toolbox drawers.
http://www.craftsman.com/shc/s/p_101...ord=multimeter

 

Dude, that's an understatement! I tried all kinds of wires and had major issues with the twin turboed Camaro. I ended up getting a stock set of GM wires and had absolutely no problems with them.

Elmer

 

I've had MSD Wires on my last (5) cars including my C6 for three years now and I've never had a problem with them on the street or the Dyno. Your wires may be faulty, but I have a feeling it is probably something else.

 

if its missfiring then sure it would cause drivability issues. know car should be tuned if it has ignition issues of course i would just swap back and move on.

 

Guess its not the wires. Thanks for the input guys. Im gonna be doing a coil pack relocation in the next few months anyway so it wont be an issue.

 

I've got MSD wires in 2 of my cars including my C6 with no issues.

 

If you have access to a scanner, look at the misfire monitor. It could save you alot of time and ag. Keep it simple, it will give you the cylinder. Then swap out 2 wires and see if the miss moves with the wire, if not try it with 2 plugs. Quick and easy.

 

I'm not so sure you aren't on to something here. My car has had intermittent driveability issues that caused me to replace the plugs last week. I noticed while I was doing the change that the MSD wires did not snap solidly into place. Once they were seated they still wiggled around and I could feel play in the connection at the plug tip.

 

After buying a new optistart which came with a new connection harness which runs from top of motor under the plastic cover to the optistart.As I was unplugging the new harness connection from top of motor I noticed it was hard to unplug.I finally pulled it off.But after I went to plug in the new connection I noticed it wasn't lining up correctly.The plastic tabs that help line it up were on the wrong side...So I looked at the old one I took off the car and it was wrong also.I'm pretty sure this 1995 corvette has never had a tune up with 50,000 miles on it. I looked into the original connector and one of the four pins was pushed all the way back due to it being forced on. I was thinking how many Lt1 vetts have this issue.I wanted to share it.I took the new connector and took a box knife and cut to plastic tab off and then it fit perfectly into the boot.This wire runs the the top of your optistart.So having a one wire not connecting good will make your car run bad or skip. This is just a added problem of the optistart problems.But sometimes missed due to using the existing harness and not using the new one.I wanted to post what I found.This could have been a problem straight from the factory or from a bad replacement part.But like I said, its looks like nothing ever got replaced on the car. I replaced the optispark,harmonic balancer, water pump and spark plugs and wires. Check your connection harness under the plastic cover above your valve covers. This connection could be incorrect but still pushed in. Unconnected it and look inside and make sure it being lined up correctly and you can see all four connector wires inside. I hope this helps my fellow corvette owners. As we share it shows we care. Drive safe!