starts fine, smooth idle 30secs, rough idle, then dies

Same symptoms on a GM SUV - it was a carboned up EGR valve. DH took it off, blew the carbon out and we repeated this about every 6 months. The valve worked like it should except got all carboned up. Is there an EGR valve on a coach?

When this happened, by the time it progressed to not running my check engine light was usually on.

april10, We had a similar problem with our Bounder, it was the spark plug wires. OEM wires lasted a long time while the replacement set died quickly. Replaced twice under the shops warranty. Cost of wires was about 150 bucks.

Thanks, I'll let my husband know.

It is a Chevy 454 engine.

Water in the fuel tank. Idle solenoid bad are the first two things that come to mind. It is also quite possible that there is electrical issues. Such as plug wires have broken down and are shorting to ground instead of through the plugs. There are literally dozens of possible causes and it will take a lot of time and patience to track them all down until you find the culprit.

Please tell us whether this is a Chevy 454, Ford 460 or other.