Community Forums

Boatman57 · 08-18-2019, 05:56 PM

Hi all...quick question bout the Chevy 8.1...we have a 2001 Monaco lapalma,coach has 45000 miles we have put a bit. Over a thousand on it ...had no problems at all till last trip .after an hour interstate speed. Hit the mountains and first time it died we had just came off a 3 mile decline so no accelerator just brakes...at bottom hit the gas and nothing.didnt think about shifting to neutral and trying to start it...lotta stuff going on all at once..anyway pulled into emergency lane caught our breath...chrcked all gauges.hit starter came back to life...let it run for a sec. Still all gauges. We're ok .went 35 40 miles or so. Same thing....luckily we were close to home still did it 3 times in last 5 miles....anyway it was mid90s if that helps......im thinking fuel pump in tank is getting weak.does those symptoms indicate the pump in yalls opinion...tks for everyone time,and enjoy the road

Skip426 · 08-18-2019, 06:07 PM

This SOUNDS like the standard Workhorse fuel pump issue; problems hot particularly with less than 1/2 tank of fuel.

Problem is confirming ; with a pressure gauge after hours of run time .

PbdBlue · 08-18-2019, 09:56 PM

Quote:

Originally Posted by Skip426

This SOUNDS like the standard Workhorse fuel pump issue; problems hot particularly with less than 1/2 tank of fuel.

Problem is confirming ; with a pressure gauge after hours of run time .

+1. Get a fuel pressure gauge on it. It’s not an uncommon failure on early workhorses. Both my buddy’s with 200x vintage chassis’s have had to replace the fuel pump. Typically the pump develops a leak in the accordion hose that connects the pump outlet to the flange. Be aware that if you do need to replace the pump you will likely find that the pump has been superseded by a newer pump with a different electrical connection so you will need to do a little rewire at the connection.

Gary RVRoamer · 08-19-2019, 12:04 PM

Before going too far, change the fuel filter. Will give the same symptoms if partially clogged.

AKIQPilot · 08-19-2019, 12:35 PM

As Gary mentioned change the fuel filter first and see if things improve. A fuel pressure gauge is very handy and super easy to install. I have them on both of my Workhorse motorhomes.

For a 2001 WH chassis the fuel pressure should read about 54-55psi at idle or anytime you lift off the throttle and about 58-60psi when driving down the road. The '01 has an adjustable fuel pressure regulator on the fuel rail on top of the engine so you can increase or decrease this pressure to get it within spec.

vettenuts · 08-19-2019, 05:00 PM

As mentioned, there were some heat related issues with earlier Workhorse 8.1 fuel pumps. Where does the return line run on your chassis? Some have had to rerun the return line. Agree, keep your tank up above 1/2 if you can, especially when doing hills.

Arch Hoagland · 08-19-2019, 06:01 PM

Do you ever get a Check Engine Light?

Boatman57 · 08-20-2019, 02:47 PM

As far as a ck engine light,I do but it's intermittent

Arch Hoagland · 08-20-2019, 02:54 PM

Quote:

Originally Posted by Boatman57

As far as a ck engine light,I do but it's intermittent

Have you put an OBD reader on it to determine what the code is?

vettenuts · 08-20-2019, 04:32 PM

The code will remain stored as a history code until you have a predetermined number of starts. You can still pull the code(s).

elbeau54 · 08-20-2019, 08:39 PM

I have a 05 allegro bay with 8.1. where is the fuel pump located

153stars · 08-20-2019, 08:44 PM

Quote:

Originally Posted by elbeau54

I have a 05 allegro bay with 8.1. where is the fuel pump located

In the tank it's a big cartige unit, pump ,level gauge sender , pickup sock/ screen filter.

Boatman57 · 08-21-2019, 05:45 AM

Code is for an ox sensor.on lost of things to replace

vettenuts · 08-21-2019, 06:16 AM

First thing to do is clean the Mass Air Flow sensor, it is directly behind the air filter attached by a large rubber tube. Check the filter while it’s apart. Don’t assume it is the oxygen sensor that is the issue. Do you have the actual code? Some oxygen sensor codes will present due to bad wires too. There are several oxygen sensor codes.