Best place in Raleigh to diagnose/resolve misfire issue? (Probable exhaust valves)
 

Hi Carolinas -
EDIT 2 - SOLVED: the issue turned out to be overly tight exhaust valves on #2. I adjusted myself and the car drives fantastic. I also took the car to Engine Experts in Raleigh to double-check everything and they confirmed they are no longer able to reproduce any issues.

EDIT: I purchased a new leak down tester and pulled the valve cover this weekend to run another full test. My results showed a 28% leak on cylinder #2 compared to an 8-15% result on other cylinders (results were 89, 72, 85, 92 psi with 100 psi input). I could certainly hear most of the leak coming through the cylinder head itself, but I also noticed some faint noise in the tail pipe vs. nothing on cylinders 1, 3 & 4. To me this continues to point to exhaust valves or a combination of exhaust valves, head gasket and/or piston rings.

All the exhaust valves needed to be adjusted but the valves on #2 were also exceptionally tight (smallest feeler gauge wouldn't even fit). I adjusted the valves but I haven't had an opportunity to re-install everything yet as I consider my options. I'm still eager to find a shop to work with in Raleigh. I have a call out to Engine Experts but after my call with them it would seem they specialize in sourcing and swapping in motors vs. diagnostics and machine shop work.

Original: I've been hunting down a misfire issues on cylinder #2 for a while now and I think I've tracked it down to a burnt/bent exhaust valve. I've run compression and leak-down tests with mixed results (showing cylinder #2 is slightly lower than the rest) but leak-down proved kind of inconclusive (the tester I purchased is basically a paper weight with gauges). Has anyone in the area had a good/bad experience with any local mechanics in this area? I'm not beyond having the top end rebuilt if that's what's necessary but I'm looking for the best shop in town to do that work.

Sent PM.

I should add that I'm decently proficient working on cars (outside of full engine/transmission repair) and that I've already swapped coils, plugs and injectors and the misfire returns. I also noticed that the exhaust sounds a little "fluttery" or pulsates at idle and tried the paper test which, unless I'm mistaken as it's hard to see on the youtube videos I've referenced, is sucking the paper back into the exhaust as it idles, indicating a problem with exhaust valves. The misfire only occurs on startup/idle and rarely, if ever under load.

Other interesting things to note:

• oil on spark plug threads on #2 (but not the others). When I swapped plug with #4 and rechecked after about 100 miles, the swapped plug also has oil on threads.
• Flashpro data logs show that the knock sensor is indicating #2 typically has a higher knock count (7-10 on a 30 minute drive, vs. 1-2 on other cylinders)

I edited my first post but also putting this here:
I purchased a new leak down tester and pulled the valve cover this weekend to run another full test. My results showed a 28% leak on cylinder #2 compared to an 8-15% result on other cylinders (results were 89, 72, 85, 92 psi with 100 psi input). I could certainly hear most of the leak coming through the cylinder head itself, but I also noticed some faint noise in the tail pipe vs. nothing on cylinders 1, 3 & 4. To me this continues to point to exhaust valves or a combination of exhaust valves, head gasket and/or piston rings.

All the exhaust valves needed to be adjusted but the valves on #2 were also exceptionally tight (smallest feeler gauge wouldn't even fit). I adjusted the valves but I haven't had an opportunity to re-install everything yet as I consider my options. I'm still eager to find a shop to work with in Raleigh. I have a call out to Engine Experts but after my call with them it would seem they specialize in sourcing and swapping in motors vs. diagnostics and machine shop work.

FINAL UPDATE: Solved

I've been CEL free for ~1500 miles now. Tight exhaust valves was the primary culprit.

Oil on the top half of the plug and/or on the coil means your plug tube seals are leaking. It's $9.80 for a pack of 4 from Beck Arnley on amazon and will take you longer to pull the valve cover than it will to replace the seals.