drove car across country now running rough??
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Joined: Jul 2007
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From: PHX, AZ USA
2003 C320 Sport
drove car across country now running rough??
I drove my c320 from Nashville, TN to Phoenix, AZ and now it is idling rough. It seems to run fine when I'm giving it gas only rough while idling at stop lights. Would the climate change cause this? Does it need to be tuned for Phoenix's climate?
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
No - the vehicle adjusts itself for altitude change. It has an aneroid arrangement.
Last edited by Glyn M Ruck; Sep 27, 2008 at 02:07 AM.
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From: Nuevo México
2005 C230K Sport Sedan, 6 speed manual
The elevation in Phoenix is only about 1300 ft. above mean sea level, so it isn't really that high. However, many of the mountains you crossed in New México and Arizona are very high.
I also suspect gasoline problems. A few thoughts:
1. Gasoline purchased in New México tends to be low octane. The entire state is at high elevation, so the octane demands are low. Premium gas is often only 89 to 91 octane, and regular is around 84 to 86 octane. I think this also applies to mountainous areas of Arizona.
2. Temperatures in the mountains are now getting cool, and you may have bought some winter formulated gasoline. Winter gas normally has a lower flash-point than summer gas. Vapor pressure may also be different (could cause "bubbling" in the injection system). Therefore it may run poorly at hotter temperatures.
3. If you travelled the normal route, you came through Flagstaff (elevation 7000+ ft.) and descended into Phoenix (elevation ~1300 ft.) in about 100 miles. Your car feels like it has fallen off a cliff. There are huge differences in temperature, barometric pressure, and demands on your fuel.
Run some Phoenix gasoline (Top-Tier, please) and Techron through your fuel system and see if it readjusts, before you panic.
I also suspect gasoline problems. A few thoughts:
1. Gasoline purchased in New México tends to be low octane. The entire state is at high elevation, so the octane demands are low. Premium gas is often only 89 to 91 octane, and regular is around 84 to 86 octane. I think this also applies to mountainous areas of Arizona.
2. Temperatures in the mountains are now getting cool, and you may have bought some winter formulated gasoline. Winter gas normally has a lower flash-point than summer gas. Vapor pressure may also be different (could cause "bubbling" in the injection system). Therefore it may run poorly at hotter temperatures.
3. If you travelled the normal route, you came through Flagstaff (elevation 7000+ ft.) and descended into Phoenix (elevation ~1300 ft.) in about 100 miles. Your car feels like it has fallen off a cliff. There are huge differences in temperature, barometric pressure, and demands on your fuel.
Run some Phoenix gasoline (Top-Tier, please) and Techron through your fuel system and see if it readjusts, before you panic.
Last edited by alpinweiss; Sep 27, 2008 at 08:09 PM.
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From: Sacramento/San Gabriel/Riverside
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um.. let's say i'm at a stoplight, and i just stay there in D, but braking. rough idling, but stays at 500 RPM. i'll look at it tomorrow in-depth, but that's all i can say for now
