slight misfire when hot

[vanagonjr]

My vans seems to run just a bit off after cruising for an extended period of time, say 3 or more hours. Misfire is actually too severe a term; it just doesn't seem quite as smooth as it is in the morning. I definitely will notice how well the engine runs the next morning on a trip for example. Note, my coolant temp is fine.

Van has new NGK plugs, OEM wires, new Bosch rebuilt dizzy and a new Bosch coil, as well as recent Bosch cap and rotor, so it seems that the ignition system should be A-OK. Timing set per TenCent's method. I checked for vacuum leaks, spraying brake cleaner (although engine was cold) and did not find any - but I am still think that is a possibility.

The blue coolant temp sensor was replaced 6 years and perhaps 10-15,000 miles ago.

Any thoughts on what to check?
_________________
John - 86 Wolfsburg Westfalia "Weekender"
Flint reversed 1.8T W/Passat 5-Speed
LiMBO (late model bus club) www.limbobus.org
LiMBO is on Facebook too! https://www.facebook.com/groups/
FAQ thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=525798

[vanagonjr]

Forgot to add van/engine details

1986, 2.1, 4-speed, P/s No AC.
_________________
John - 86 Wolfsburg Westfalia "Weekender"
Flint reversed 1.8T W/Passat 5-Speed
LiMBO (late model bus club) www.limbobus.org
LiMBO is on Facebook too! https://www.facebook.com/groups/
FAQ thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=525798

[djkeev]

Check for an intake or vacuum line leak when hot.

Dave
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