Thanks, this is most helpful! The car actually passed emissions
testing today, and I'll probably plan on replacing the EGR valve soon.







On Tue, 22 Dec 2009 08:46:29 -0500, "Oppie" >
wrote:

>Let's go with the EGR valve possibly sticking open. Any gross vacuum leak,
>including excess EGR flow, will cause the RPMs to kick up.
>
>The fact that you had a loose battery cable probably lost some of the
>adaptive settings in the ECU. This is re-learned as you drive (the 'drive
>cycle') and may correct any problems after 50-100 miles.
>EGR related codes (most codes for that matter) are not set in memory until
>the engine is at normal operating temperature...coolant level, thermostat
>and coolant temperature sensor (CTS) are responsible for this. For that
>matter, an open CTS circuit often causes high idle and rich fuel mix. Check
>that the CTS cable is not pinched or loose at the sensor. I've seen worn
>motor mounts that allow the engine to twist and put tension on loose
>harnesses.
>
>"Buzz" > wrote in message
>news
>> My '96 SL single cam has 185K on the clock, and has been running fine.
>> A few weeks ago I changed the oil and hosed off the motor with a
>> garden hose. Then the "Service Engine" light came on, but it was
>> running fine. A few days later it went off, and my buddy at work
>> hooked up his code readed and said it had a EGR related code in the
>> memory.
>> I drove it a couple of weeks, and light stayed off. It wouldn't start
>> the other day, and wiggling the battery terminals got it to start, so
>> I drove it home and cleaned the terminals, which really didn't look
>> bad at all, but I polished them bright with a wire wheel.
>>
>> The next time I drove it after the terminal cleaning, the engine had a
>> high idle, and would race up to 3000 RPM when I would clutch it
>> between gears. the idle would eventully settle down to 750 RPM.
>> Drove it to work today, and it still would race up between gears,
>> almost like I wasn't letting off the gas pedal when shifting. When I
>> would put it in neutral coasting up to a stop, the engine would be at
>> 2000 RPM, then slowly drop to a 750 RPM idle. No check engine light
>> is coming on at this time.
>>
>> What could be causing this?