I have a 2005 Fleetwood Excursion on a Freightliner XC chassis with a 350 hp Cat C7. I drove it about 40 miles two weeks ago and it ran fine, accelerated good and ran 55-60 on the highway no problem. Yesterday I started it up tried to back out of my driveway and it would not make it up the small grade. It started easy, idles good, and will rev up when in neutral, but when in gear, forward or reverse, the throttle pedal goes down and nothing. I thought maybe it was fuel filters so I changed them this morning, no change. Any help would be greatly appreciated.

I had a MH in my CG with the similar problem on a Cat engine. I forget now which sensor's plug (near the fan) was dirty and cleaning it solved his problem. May take hooking it up to a computer to see which sensor is not working correctly or try cleaning all of the two wire connectors you can get to.A Cat/Allison will do the same thing until it warms up but doubt it's cold enough for it to do that. Worth giving it more time to warm up and see if it will accelerate after a couple minutes.

No code-check engine? Are you sure a brake isn't dragging? Maybe time to buy a Silver Leaf setup for your laptop.

I cannot rev my engine if there is not enough air pressure.

When was the last time you changed the Fuel Filters?

Sounds like it is receiving some information from one of the sensors that is putting the engine in to limp mode.

Cat C7 starts, idles, but won't rev up in gear.

Rolandh
Explorer
Jun 16, 2024
Randy. Were you able to fix this problem as I have one that has the same issue?
- bid_time
  Nomad II
  Jun 17, 2024
  Randy hasn’t been on here in almost 10 years so it isn’t likely he is going to respond to your inquiry. However, if you would have read down through a few posts you would have found that Randy changed the air filter and it solved his problem.
  - Rolandh
    Explorer
    Jun 22, 2024
    Thank you. I asked the question before I signed up so I couldn’t see dates or other post
msmith1199
Explorer II
Jun 22, 2015
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FIRE_UP
Explorer
Jun 22, 2015
I'm not overly trusting in those filter minders. We had them on all our fire trucks and, just like when I changed it on our motor home, they all read the same thing when we changed them on the fire trucks after quite a few miles. Mine on our coach, was never changed prior to 50K miles and, it read about half way. I changed the air filter, and reset it and, it read about half way. So, it's simply a "catastrophic" reading that I will have to pay attention to.
Scott
Randy_A
Explorer
Jun 22, 2015
Air filter minder was getting down to the last open yellow line, but I recall that when I replaced the air filter 3 years ago I reset the minder and it almost immediately when back toward that area. The filters I get from Freightliner are Racor. I haven't cut it open, and probably won't, but it does feel heavy and dust flies when I bounce it on the concrete shop floor. I travel from PA to WY and back each summer and PA to FL and back each winter. I don't drive on any dirt roads by choice, maybe some dirt driveways, but very limited, have been forced to use a few dirt construction zones in WY, but again very limited. Who knows where that much dirt came from, but it works now. I do need to reset that filter minder and see what it does this time.
Diplomat_St_Poo
Explorer
Jun 22, 2015
It was a few years ago so I an not sure what our air filter minder said. Although I would have thought the Cat Service would have checked it and they didn't mention the air cleaner at all.
wolfe10
Explorer
Jun 22, 2015
Yes, what was your AIR FILTER MINDER reading when this occurred?
RayChez
Explorer
Jun 22, 2015
Racor sells the best filters for those cat engines. I have been very happy with the more power I got when I switched from the Napa air filters.
SCVJeff
Explorer
Jun 22, 2015
Out of curiosity, do you have a back pressure gauge on the intake, and what did it say?
Diplomat_St_Poo
Explorer
Jun 22, 2015
Excellent news Randy A.
When it happened to us the cat service centre we limped into did not solve it either. They pulled the codes, they said low fuel pressure, changed fuel filters but it didn't help. My husband and I talked it out while camped overnight in their parking lot. Husband pulled out the filter the next morning, run perfect.
Had to search around a few places for a replacement (cat service didn't have one). Finally found a cleanable one. Back to full power :)

Thanks for the follow-up.
wolfe10
Explorer
Jun 21, 2015
Randy,

Cut the old filter open. Look for excessive dirt or signs that it got wet. Water is a real killer of paper filters (doesn't matter if gas or diesel).