Community Forums

PapaD · 11-30-2010, 07:04 PM

I just took my 2005 WH 8.1 on a trip. On the way I noticed the mileage dropping from about 6.5/7 MPG to 6.3/5.5. I also noticed a loss of power. I could press the accelerator but until the Allison down shifted it would not pick up speed. I also notice climbing hill speed and power decreased. As I was 300 miles from home, I chose to leave the MH with a mechanic and drive back home in my towed. I have some ideas what may be causing the loss of power and mileage but I want to hear other suggestions. I previously changed the air filter and rechecked it so I don't think this is the problem, although it does sound like the symptoms of a bad air filter.

Thanks, and Merry Christmas

PapaD

RV Mech Tech · 11-30-2010, 07:15 PM

PapaD - when is the last time you changed the fuel filter ? - have the mechanic check the fuel pressure -a plugged fuel filter will decrease the fuel pressure and starve the engine - resulting in loss of acceleration and power.

UFO Pilot · 11-30-2010, 07:44 PM

I would suspect a plugged fuel filter or burnt plug wires.

edgray · 11-30-2010, 08:14 PM

Have you had the brake recall completed yet?

Arch Hoagland · 12-01-2010, 12:08 AM

How many miles are on your coach?

As edgray asked, have you had the brake recall done yet? You might be seeing the brakes not releasing correctly.

I carry an infrared gun and check my tires and brakes at every stop, looking for abnormal high temps.
Let us know what they find out with your coach...

Jackm · 12-01-2010, 03:30 AM

At 7 mpg, those little filters sure filter a lot of gas. However, if you haven't had the brake recall done yet, I would guess that some of the calipers are locking up. If this is the case, you'll feel lots of heat from the wheel(s) and a creaking sound as the rotors contract and expand. It isn't pretty.

Jack

PapaD · 12-01-2010, 12:04 PM

My MH has 24500 miles. The brakes has been done on one wheel only. I had an issue in the summer with overheating on that wheel. I still need to have the total recall performed. I could feel the engine cut out once in a while. Also the MH was not running up to par when I drove it to the mechanic. The fuel filter has not been changed to my knowledge and is what I suspect is the culprit. That is the first thing I am having done.

RV Mech Tech · 12-01-2010, 04:00 PM

PapaD - usually a plugged fuel filter is unlikely at that low mileage unless you have contaminated gas but if that were the case then the engine would not perform at all and even stall and backfire but have the filter checked as a precaution - if something is wrong with the gas and the lack of power is a fuel problem the engine may have started to ping and then the power (engine) control computer may be cutting back the timing on the engine to prevent damage and in severe cases the check engine light will come on- since you did not ention anything about the check light coming on you may have to have the engine computer scanned to find out what's wrong - let us know what you find.

Brazel's RV Performance · 12-01-2010, 04:23 PM

Have them check the plug wires, and not just stare at them; have them pull each off and verify that the boot is not burnt internally...did it feel like it was missing at all?

PapaD · 12-01-2010, 06:40 PM

It is possible the engine had a skip. I can't be certain if it was electrical or fuel causing the roughness. Once it was up to speed (65/70) it seemed to run fair but not much in the acceleration after pushing the pedel further and the mileage did increase a little before I arrived but that could be due to running at slower speeds.

Thanks for all the help and suggestions

PapaD · 12-05-2010, 07:17 PM

Just wanted to let everyone know, I had the fuel filter changed and new plugs installed. I picked up my MH Saturday and drove it home (300 miles) Sunday. I had more power than I remember ever having and the mileage has gone back to 6.5 to 7 MPG. Sometimes as high as 8.5. Seems this was the culprit.

Thanks again for all the input and assistance.

Merry Christmas!

**JohnRR** · 12-05-2010, 07:31 PM

Thank you for the update, sounds like I'll change my fuel filter while it's sitting this winter before I have any complaints just to be sure. I just turned 25K last week or so but it seems to run good but what do I know I've only had it for 6K miles and a couple of months.

RV Mech Tech · 12-06-2010, 10:33 AM

PapaD - glad to hear the problem was something minor and didn't cost mega $$$$$ - it sounds like the filter was just starting to plug up - when the filter is almost 100 % plugged up the O2 (oxygen) sensor(s) in the exhaust system will sense an increase in the oxygen in the exhaust (lack of fuel will cause this and an over rich mixture will decrease the oxygen reading) and this will turn on the computer or 'check engine' light -sounds like you caught it just in time.