FYI - Gen 2 running rough and stumbling - needed a new battery

[twinbopilot]

My '98 started to idle rough and act like it had a bad COP or clogged fuel filter but no codes showed up, and no CE light. The next evening the car wouldn't start due to a weak battery. Battery showed 13.8 volts on my meter. Took the battery in, had it tested, and the report off the machine said it was only producing 430 CCA instead of the 850 its rated for. So I had them install a new battery, and my rough running, stumbling problem went away. Just a thought for the next time your engine starts to run rough with no apparent reason...obviously the bad battery was somehow reducing the voltage available to the car's system. I always thought if your alternator was good, your engine should run fine, even with a weak battery. I've read about the same weak battery/rough running issue in the LS forum but I experienced it in real life on my Mark VIII!

 

[87TTOPGT420]

by unhooking the battery you cleared any code it may have had when it was running rough and in turn could have corrected the error wouldnt be suprised if it came back

 

[twinbopilot]

I checked for codes BEFORE the old battery was removed and replaced, but I see your point now.

 

[dcrews]

One thing about getting your battery tested....

When you go to a parts store with the battery, aways have them test it inside on the "big" machine.

The hand-held machines most stores use can be "fooled" into producing in-accurate results.

I'm a manager for a parts store, and run into this all the time with my new employees. If you don't enter the settings correctly (especially temperature), it could throw a 'bad battery' even if it's good, and vice versa.

The 'big' tester inside doesn't need that information. As long as the CCA is inputed correctly, it will produce an accurate result.

Just an FYI for anyone who thinks they may need a battery, since it is gettin cold outside.