Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 08-05-2012, 03:56 PM   #1
Junior Member
jdc4x4's Avatar
Join Date: Apr 2012
Posts: 7
Vapor Lock?

I have a 2003 Holiday Rambler w22 with an 8.1L GM engine. I am driving through Oklahoma in 95-100 degree weather with the AC on. Suddenly, pushing on the gas pedal no longer gives power. When I slow down to pull over, the engine stalls. I put it in park, wait 30sec and the engine starts back up with no problem. This has happened twice in the last 100 miles. We are not yet completely broken down but, if possible, I'm trying to identify the issue before it gets worse.

I am thinking vapor lock, but, wanted to reach out to see if anyone has any ideas. I'm really hoping it's not the fuel pump..


jdc4x4 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 08-05-2012, 04:43 PM   #2
Senior Member
chuckftboy's Avatar
Fleetwood Owners Club
Holiday Rambler Owners Club
Join Date: Dec 2011
Location: North East Florida
Posts: 571
Your fuel pump should be in the tank with a fuel return line which should pretty much eliminate vapor lock. I've had that happen on my Chevy 1 ton work vans, more than once and it was fuel pump on all 3 these trucks had over 1000,000 miles on them. Good luck. I hope you don't need a fuel pump, they are not cheep

2015, HR Ambassador 38DBT / 2006 Jeep TJ Towd
340 Cummins / Freightliner Chassis
chuckftboy is offline   Reply With Quote
Old 08-05-2012, 07:04 PM   #3
Community Moderator
"007"'s Avatar

Nor'easters Club
Workhorse Chassis Owner
iRV2 No Limits Club
Join Date: Oct 2004
Posts: 24,494
Welcome to irv2 jdc4x4.
You may need a heat shield near your fuel line or return line to tank. Check lines near your exhaust pipes.
Something else if its raining could get water into your air intake horn that will put engine into a safe mode with 1/2 the power.
98KSCA, 99MACA, 03 KSCA-3740- 8.1 Chev-- ALLISON Trans, now in good hands
"007" is offline   Reply With Quote
Old 08-05-2012, 08:37 PM   #4
Senior Member
Ford Super Duty Owner
Join Date: Apr 2012
Location: Austin, TX
Posts: 1,867
We've had MPI (fuel injected) boats that love to have this problem. However, their pumps are not in the tank and their fuel systems do not recirculate.

I am, however, having the issue with a generator.

If I had a modern 8.1L, I'd see if it's setting any codes (check engine). If not setting any codes, I'd probably get a OBD-II scanner that can show me real time data. (Note, if you use an Android phone, you can do this for under $30 total... )

If vapor locked, you'd measure near zero fuel pressure.

Last way to check - and this is more dangerous: Find the schrader valve on your fuel rail. Let it stop, depress the valve. If vapor locked you'll get air. If not, you'll get fuel. Note spewing high pressure fuel on hot motors is dangerous, so the standard disclaimer of - have a mechanic do it is in order...

To gather more evidence without all of the difficulty above:
1) Switch to running your coach AC off the genset.
2) Drive in the morning or in the evening after the sun is down. Pavement temperatures right now are crazy, easily over 120 degrees.
cb1000rider is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 12:38 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.