6.9 Stumble at idle and hard hot start

[Rolo]

I couldn't find an existing thread on this so apologies if already discussed.  My 6.9 was running great and then it died while driving off from my mechanic.  He turned up the idle screw and it stopped dying.  But since that episode, car has an intermittant stumble at idle in Drive and is very hard to start when hot.  I also get a very slight miss fire when accelerating off the line.  Miss fire disappears under throttle at speed.  MPG has fallen to 9 mpg when driving in town.  Still okay on the highway.

One thing I asked him to check when he had it was getting full throttle.  Car was a little weak at full throttle.

Car has fairly new distributer, plus about 15,000 miles on the sprak plugs, and fairly new injectors and like I said was running great before the visit to the mechanic.  Any thoughts on the cause?

[daantjie]

Usually hard hot start points to shot fuel accumulator.

[Randys01]

Sounds like the mechanic's visit was a turning moment in what was an otherwise nice running car.
Has he inadvertantly knocked something off/broken something.?
What was the scope of work? You said he needed to check full throttle......there's ample scope in this simple job to disrupt some vacuum lines.
You are going to have to revisit his steps and eliminate  both electrical issue and vacuum.
Ensure/double check  that everything is correctly and firmly fastened....
In partic make sure the distrib button is on squarely and firmly..plugs on firmly on at both ends etc etc

[Rolo]

Thanks for asking.  He adjusted the throttle linkage.

[Randys01]

If all he did was to adjust the throttle and the car was running fine b4 it went in and played up on the way out then something has been disconnected inadvertantly in the process.
If you are not confident  in ratting it down then take the car back.

[raueda1]

Thanks for asking.  He adjusted the throttle linkage.

Seems like something missing in this story.   Randys01 is almost certainly right about knocking something loose IMO (and he knows way more than I do!).  But back to the beginning.  You say car was running well before except for being weak at full throttle?  Was this something that happened all of a sudden and the original reason to go in? In any case, before going back, I'd pull off the air cleaner and take a close look at everything.  The cause may be obvious.  Finally, did he work on anything other than the throttle?  If so he may have reconnected something wrong.  You may also want to have a look at THIS old thread. Cheers,