03 8.3L Aerbus Engine Issues

[tkoden]

I have an 03 Aerbus with 8.3L workhorse engine. When we are cruising the engine runs fine but under load it misses and runs like ****. The engine has 24k miles on it so I'm not sure where to start. I am pulling the spark plugs now to check gap but looking for other ideas. We are trying to go on a trip this weekend so any help is greatly appreciated.

[rgatijnet1]

Some coaches had a poor front end design and allowed water to be sucked in to the intake. IF your air filter is wet, this can also cause the missing.
With a little cutting, you can turn the intake horn 180 degrees and eliminate the problem for good.
Brazel's RV Performance, which does a lot of work on Workhorse 8.1L engines changes the plug gap from .060 to .045 for added performance.8.1L spark plug gap
Taylor Extreme plug wires work the best along with ACDelco 8006 heat shields.

[tkoden]

I will definitely give that a try when we head out.

Thanks

[J-Rooster]

Kirk, something else that will help is next time you fill the Bus up add 3 cans of Seafoam to 50 gallons of gas. That will clean out your fuel system! The cans are $6.94 per can at Walmart! My 8.1 Vortex wouldn't run at slower speeds under a load, a friend recommended the Seafoam treatment to me and it worked wonders! I'm just passing it on! Good Luck!

[tkoden]

When we pulled the plugs 2 of the sparkplug wire ends fell off. We are going to put new wires on it and see how it does. If it doesn't fix it we will look at the coil packs.

[usersmanual]

tkoden wrote:
I have an 03 Aerbus with 8.3L workhorse engine. When we are cruising the engine runs fine but under load it misses and runs like ****. The engine has 24k miles on it so I'm not sure where to start. I am pulling the spark plugs now to check gap but looking for other ideas. We are trying to go on a trip this weekend so any help is greatly appreciated.

there is ZERO chance its plug gap and doubfull its plugs those are iridiuum plugs good for 100000 miles

coil packs and wires have been a problem at times on the 8.1

[timmac]

Check spark plug wires, coils, spark plugs and maybe its time for a fuel filter, also how old is the fuel in gas tank, since its a 03 I would go ahead and replace the plugs, plug wires, check or replace coils and install a new fuel filter and put in 2 to 3 cans of sea foam into gas tank if the fuel is less than 6 months old.

[FunTwoDrv]

If it's a GM 8.1, check the coil packs as well as the plug wires.
good Luck,
Gary