Misfires

[slickdawg]

2010 sho with 188,000+ miles. Not often but on Rsre occasions it has a misfire on one bank. Turn the car off, wait a minute and restart runs fine. Anyone else have this?

 

[Irish Pride]

Moved to proper location.

 

[Texas Marauder]

Original coils? When were spark plugs changed?

Are you using a scan tool to actually see misfire counts on each cylinder?

 

[slickdawg]

Not original coils and plugs were changed about 10000 miles ago. Doesn't do it all the time just rarely, about 4 times in the last 2 years. Scan tool is just a reader.

 

[kryptto]

If you have the old coils, put it in the bank having issues see what happens.

 

[Texas Marauder]

The misfires are only on bank 1, the rear bank? All 3 cylinders, not necessarily at the same time? I'd swap the coils bank to bank and see if the misfire follows.

It could be injectors. A buddy of mine has an Expedition that misfires on cyl 4. Plugs are new, swapping coils makes no difference. Relative compression is even on all 6 cylinders. That leads me to an injector problem.

Maybe try a bottle of Lucas Deep Clean Fuel System Cleaner.

https://www.amazon.com/dp/B003JTYGPO