Missing, rough idle after setting a few days (2 Viewers)

[girupb]

We took a few days off to vacation and when I got home I started the LX to get it out of the garage and it had a very rough idle and seemed to be missing. I reved it slightly a couple times and it smoothed up and runs great.

My only guess was hydraulic lifters bleeding down but the 80 has solid lifters. What do you guys suspect?
250k on the odometer. Runs good, power seems normal. HG shows no signs of giving up. Coolant looks fine and the overflow reservoir stays pretty steady.
It does get lousy mileage but I run the school commute every morning and then to work. Maybe 4 miles total and all of it up or down hill averaging 15-20 mph with heavy 285s

 

[baldilocks]

Sounds like you have a healthy Landcruiser that hicupped. What do you consider lousy gas mileage?

 

[Tedward]

It farts one time and its got Chron's Disease?

That's all, I have nothing helpful other than 15 to 20 mpg is darn good.

 

[Adatemp1980]

my '97 LX with 238K does the same after sitting a few days...Im no mechanic but always just assumed maybe alittle oil was getting past valve seals while sitting and causes the few seconds of rough running? Otherwise truck runs great

 

[martinakl]

my '97 LX with 238K does the same after sitting a few days...Im no mechanic but always just assumed maybe alittle oil was getting past valve seals while sitting and causes the few seconds of rough running? Otherwise truck runs great

Mine does it after sitting for awhile too. 97 LX with 183K miles. Once I give a little gas, it goes away. Runs perfect other than that.

Might be related, might not but:
I recently changed my spark plugs and noticed small amount of oil above the threads on a couple of the plugs. Tells me it's time for some new spark plug tube seals. Going to get that done soon.

My 7 year old battery is also probably ready to be replaced.

 

[girupb]

Sounds like you have a healthy Landcruiser that hicupped. What do you consider lousy gas mileage?

I get 8-9mpg with the normal commuting. Closer to 12 on the highway.

 

[baldilocks]

How old are the O2 sensors? They can become a culprit prior to being bad enough to set off a CEL.

 

[LC4LIFE]

a little oil was getting past valve seals while sitting

^this^

 

[Cass007]

my '97 LX with 238K does the same after sitting a few days...Im no mechanic but always just assumed maybe alittle oil was getting past valve seals while sitting and causes the few seconds of rough running? Otherwise truck runs great

Same for both of my 97s. They let out a little white smoke upon startup after sitting a while, but the idle smooths out in 20-30 seconds.

 

[girupb]

How old are the O2 sensors? They can become a culprit prior to being bad enough to set off a CEL.

I put Denso O2 sensors in about 3 years or 15k miles ago.