Runs rough under load

[IrishRover]

Greetings,

I have a 2007 Adventurer with a Workhorse chassis. My main issue is when on the highway and putting the engine under a load (going up a hill) as the downshifting occurs and I then feed in the gas pedal, I am getting a popping and bucking going on until I ease off on the gas pedal.

My repair guy suggested I may have a bad fuel filter which I am willing to try. The problem I have is where is it located, or where can I get a service manual depicting same.

The RV has 30,000 miles on it and the tech did not figure I ws due for a "tune-up". But something is definitely not right.

The VIN starts 5B4MPA......

All your helpful suggestions will be warmly received.

Thanks

IrishRover

[ralph0808]

Mine was doing same thing and replaced my air flter. Engine runs better and improved mpg about .5 per gal. But it did stop all the popping an sputtering. But the guys on the workhorse site will have many suggestions for you. Good Luck!!

Ralph

[edgray]

IrishRover:

Your W-24 chassis will have a fuel filter located inside the driver side frame rail just above the rear axle. It is "most likely" to be the infamous "3 fittings" filter which is NOT available at normal parts houses. Unfortunately, the original style filter is also not too likely to be in stock at a Workhorse dealer, either. They now offer part # W8006869 which is an adapter and filter that allows you to buy readily available filters in the future. I suggest you contact your nearest Workhorse ASC or call one of this sites sponsors, either Brazel or Redlands, and ask them to ship the adapter kit & filter to you.

FWIW, I doubt the filter is the cause of your mis-fire under load. Any competent shop with an OBD II tool should be able to identify which spark plug and/or wire is causing the problem. Good luck.
Ed

[max49]

Yea I'd bet on Classic burnt wire syndrome. Check SP wires, I'd suggest checking #5,6,7,8 in that order. Just pull the cap off, if it does'nt fall apart, put it back and go to the next one.

[bachler]

On my gas unit I changed the fuel Filter every 25000. miles, Think about . At 10 MPG that is 2500 gallons you put through that 1 1/2" by 2 1/2 " filter . Change it..... On the gas I allways carried one with. I have pulled to the side of the Road and changed the Fuel filter many times.. It's no big deal..

[WeatherTodd]

get with OEMY... he has a nice kit for the fuel filter.

[RottenRalph]

I had a miss under load that turned out to be a spark plug and wire at 35,000 miles on the odometer.

[WeatherTodd]

keep in mind the ethanol fuels are harder on ignition parts... 100k platinum plugs in our service trucks are lucky to make it to 60k.

[Ustamiata]

Almost certainly spark plug wires. Try racing wires from Summit -- they will take the heat.

[Duner]

IrishRover,

I've had two occasions of burnt spark plug wires. The wires burn off right at the connection point to the tip of the spark plug. The burnt wires are almost always the 2nd to the rear or the rear plug on either side of the engine. I burnt mine when climbing some long steep grades, but the missing and surging showed up on the next trip when I hit a really rough RR-xing and that's when the wire physically fell apart. They can be burnt but the gap is so close together that the engine seems to run ok most of the time.

After the second episode, Workhorse, installed their "vent kit" under warranty. About the same time I bought the UltraPower which helps the engine run a bit leaner and cooler at the exhaust manifolds. I also installed the Taylor plug wires. Since then, I've put 40,000 miles on the coach with no more troubles.

On these 8.1engines, a lot of motorhome builders don't provide good air flow around the engine compartment. When I was at the WH factory, the service manager told me that Winnie's problem is they have a flat vertical surface at the rear above the engine. As a result, the engine doesn't get enough air flow at lower speeds under heavy load.

Good luck getting your's running good again,
Bill

PS: I suggest changing the fuel filter too as preventive maintenance. The fuel filter adapter from OEM Enginnering works like a champ!

Here's the pictures of the vent kit passenger side (drivers side, not shown but looks the same):

[Bruce C]

Have to agree. IMO burnt plug wires. But filter would be a wise idea to prevent future troubles.

Quote:

Originally Posted by edgray IrishRover: Your W-24 chassis will have a fuel filter located inside the driver side frame rail just above the rear axle. It is "most likely" to be the infamous "3 fittings" filter which is NOT available at normal parts houses. Unfortunately, the original style filter is also not too likely to be in stock at a Workhorse dealer, either. They now offer part # W8006869 which is an adapter and filter that allows you to buy readily available filters in the future. I suggest you contact your nearest Workhorse ASC or call one of this sites sponsors, either Brazel or Redlands, and ask them to ship the adapter kit & filter to you. FWIW, I doubt the filter is the cause of your mis-fire under load. Any competent shop with an OBD II tool should be able to identify which spark plug and/or wire is causing the problem. Good luck. Ed

[edgray]

Quote:

Originally Posted by Bruce C Have to agree. IMO burnt plug wires. But filter would be a wise idea to prevent future troubles.

In my earlier post I inadvertantly listed the WRONG part # for the Workhorse filter adapter kit. Sorry!

The correct # is : W8006889

As others have suggested, you may also find the appropriate style filter on Oemy's website : www.oemys-performance.com , however I think you will find he no longer offers the adapter kit previously sold by OEM.

Hopefully Dale will chime in here and give us an update on what he currently has available regarding fuel filters / adapters for the later model chassis.

Ed

[IrishRover]

Thanks one and all for your assistance in this matter. I have ordered the fuel filter adapter kit. Does anyone know the replacement spark plug wires for the W24 8.1L engine?

Regards

IrishRover

[George Z]

Quote:

Originally Posted by IrishRover Thanks one and all for your assistance in this matter. I have ordered the fuel filter adapter kit. Does anyone know the replacement spark plug wires for the W24 8.1L engine? Regards IrishRover

Got my wires from www.oemys-performance.com
Gave him a call and they were shipped the same day. Great service and competitive pricing.