So I got a used Evo 8 with little in the way of service history, so I've been doing all the basics so I know where it stands. Oil, tranny and tcase fluid change, etc. Went to do the spark plugs--looks like they were the stock at 45k miles. Switched to NGK BPR7EIX sparks, and also got replacement OEM spark plug wires/boots for the coil-on system.

Upon first start I hear a misfire, service engine light comes on, etc. Seems like it's limping on 2 or 3 cylinders, unsure.

Put everything back--old spark plugs and wires. Notice one of the new ones was really sooty already, so I assume misfire on that cylinder. But now, putting it all back to old parts, still the same--service engine light, limping along, etc.

I'll add that it seemed fine before, no misfires or anything. So seems directly related to something I did.

Don't know where to go now. What's the right process to troubleshoot if it's plug, wire, coil, something else? Hope it's not going to resort to a tow to a shop (nearest Evo shop is 50 miles away...), or a mobile mechanic.

Thanks for all the advice.

 

You didnt drop anything in cylinders forsure?

 

What code does it set?

 

Isn't throwing a CEL yet--only Service Engine Soon light is on. Using my OBD2 reader, it's not showing any codes. Should it be even if only the SES light is on? (if so then it's my OBD2 reader that sucks--using a Bluetooth one with Torque Pro on my Android phone)

 

Pretty sure I did not.

 

is everything hooked up correctly? cylinders 1 and 4 should be together, cylinders 2 and 3 should be together

sounds like one set of plugs isn't connected properly and isn't firing. car will run on 2 cylinders, but it won't like it

 

Looks like I figured out the issue--or I think I did. Looking at one of the coils (2 and 3), where the wire for cylinder 3 connects to it I noticed that there's no more metal contact 'sleeve' inside the plastic part, whereas the coil for 1-4 does. Maybe when I pulled it out to replace the wire, the sleeve went with it (and subsequently lost--I can't find it), so it's not making contact and therefore not making a spark to cylinder 3.

I have a coil coming from eBay I just happened to buy used since I was cheap, so I'll try replacing it. Can I get non OEM coils anywhere else? Trying to keep costs down, so if it's replacing the coils could I get something like this:

http://www.ebay.com/itm/New-Ignition-Coil-Pack-for-Mitsubishi-Lancer-Evo-5-6-8-9/182223112479?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38530%26meid%3Da93e9100dd6e4594ade3da09da0cb1dc%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D272208104417
(Unsure if there's really a big difference between OEM, cheaper ones like this, more expensive ones, etc...)

 

If you got a light you got a code.

 

You can replace the wires and also the coil boots. The boot kits come with new springs and stuff for the center.

I totally forgot there is only 2 coils. So makesure they are in the right place even though its kind hard to get them wrong.

 

Did it fix your problem? Any updates?