potential engine shake fix...at Idle High fuel trim

[BG1988]

if your engine has a random strong shake at idle


check your spark plug cables

Found 2 loose cables not plugged in all the way..

Long term fuel trim is now corrected... highest i have seen is 6+ and +3 on average... which is good enough

instead of +12 to +15


my MPG has also been restored as well i was struggling to get more then 13MPG on my 6.0L back to 18 to 20mpg

 

[OR VietVet]

Were these wires OE, installed by you or installed by a shop? Glad it got figured out.

 

[BG1988]

Were these wires OE, installed by you or installed by a shop? Glad it got figured out.

it was having the issue before putting new plugs in/wires but the idle speed is 100% stable now before it would drop a few RPM like if the timing was off i.e 593-614 idle rpm (it would fire late...). I was chasing a non existent vacuum leak...


#4 and #6 had the incorrectly seated cables, this could explain the extra O2 detected by the O2 sensors.... I know a lot of people a chasing a so called vacuum leak...


have not had an issue with it surging when starting ... sometimes it would go to 2k rpm 1000-1100 should be typical on a cold start

 

[OR VietVet]

Plug wires, push and then click and a slight shake to double check. Once I push and feel the click, I push again to a-n-a-l check.

 

[BG1988]

Plug wires, push and then click and a slight shake to double check. Once I push and feel the click, I push again to a-n-a-l check.

i actually checked them a few times before maybe i was being too gentle as not to damage them