ugly plug photos

[clinebarger]

Originally Posted by SteveSRT8
Originally Posted by clinebarger
Don't these vans have a PTO? Is the high idle working correctly?

The high idle is controlled by a black box through the diagnostic plug. Three different speeds 900, 1500, 1750 rpm selectable by the user.

The truck runs excellent and ran quite well before the plug change amazingly.


Maybe 900rpm isn't enough? Though this probably has a direct drive PTO as a 6L90E doesn't have gear reduction PTO provisions??

I'm just spitballing here Steve, But lugging an engine can cause issues assuming the operator is only using the low rpm setting?

 

[SteveSRT8]

Astonishingly the truck has a FACTORY REQUIRED plug change specified for 60k miles! News to me, as it was always 100k.

 

[cronk]

Wow, does make you wonder if there was a bad batch of plugs or something.
I took a set of AC Delco iridium plugs out of a 2.2 ecotec that had 180k miles and they were badly worn, but looked better than those.
Fyi, most of the Delco iridium are relabled NGK laser iridium, and are made in Japan.

 

[SteveSRT8]

Originally Posted by cronk
Wow, does make you wonder if there was a bad batch of plugs or something.
I took a set of AC Delco iridium plugs out of a 2.2 ecotec that had 180k miles and they were badly worn, but looked better than those.
Fyi, most of the Delco iridium are relabled NGK laser iridium, and are made in Japan.



I have also run these plugs to ridiculously excessive mileage and never had a misfire. Something is very different here.

And to clarify, the manual says 97,500 miles for replacement in the severe schedule. But we do tons of stationary operations that GM counts as 33 miles each hour. So 1500 hours is 49,500 miles additional.