Donny

I just replaced my battery and the first thing I noticed was this strange drop in RPMs. Normally the tach would hover around the 1k range. Now I often drop down as low as 600rpms and the car almost putters like it might stall. Here is a quick video I shot this morning. What are the thoughts? Has anyone had this problem before?


http://www.youtube.com/watch?v=RSDa3iHBhbY

evilempire18

iTrader: (3)

never happened prior to the battery replacement? how many miles did you drive it after?

Donny

Drove about 25 miles, never happened prior. Has anyone seen this before?

Berts24

iTrader: (3)

I've seen it before but never on an evo and never after replacing a battery

4g63Moon

iTrader: (9)

Thats weird I replaced mine and never had that problem. tell us what the problem was if you find out!

evilempire18

iTrader: (3)

I would continue with the drive cycle (75-100miles) and let the computer relearn itself and see what happens.

Donny

Will do, I'll keep everyone posted. Thanks for the feedback

compscibOi

iTrader: (19)

Was that a warm start?


when you disconnect the battery, start it up and let it struggle for about 15 minutes. The ECU will relearn how to idle.

I'm betting this is what the issue is. Start it, let it idle for 15 minutes then drive around... report back

nonschlont

iTrader: (3)

+1 Usually u could just let it idle for ~10 mins. and it should re-learn... Never seen this becasue of a battery replacement, but when u disconnect the battery cable, it resets the ecu.

compscibOi

iTrader: (19)

^ yep

nonschlont

iTrader: (3)

ya beat me to it...

clubEVO93

iTrader: (8)

Ive had the same problem. It always does it when idling. drops to about 650 rpms and then picks back up.