back firing under load

going to have to suspect an EGR valve full of carbon...take it off and spray it with brake cleaner or buy another one~

under load, Jim? a romantic thought to condemn the ignition...sad the EGR is not working correctly....touchy technology at the outset...add use and carbon becomes tough to get any answers out of this criminal~...a nice Idea, to "cool down" the combustion with it's own exhaust, but when not doin' it right makes waste of an otherwise perfectly good motor~

the onboard diagnostics will have something to report...get the diagnostic info please....get your own OBD-II scanner...this might help to pinpoint the culprit~

wow. Jim, thought for sure this had a troublesome TPS that would send errant signals to the ECU causin' the backfire but sounds like yours doesn't have one, but the ole' fashion cable type throttle?---my bad~

the report would wring-up a TPS (maybe) as this being the only connection between you and the computer will see a lot of use and hopefully took the time to make it an optical device rather than a "feather weight" sweep~.....fail....

...at these prices would be kind of a fool to NOT go for it, even if this WEAR item isn't worn yet~

Sorry to bother you guys but has he checked his fuel pressure? and is this an actual BACKFIRE? I get these descriptions sometimes and go drive it and find it is better described a little different. Have replaced loads of egr valves, but never a thermactor diverter. Lots of exhaust check valves though. I know, I know- must see to appreciate. hope a few other ideas help.

I have a same motor home and same problem what did you find out what was wrong with it