2000 XJ - stalling issue

[JeepsterXJ]

My battery died while I was putting in a new trackbar. Charged it up a little, and went to start it. Strong cranking, but no start. Took me giving it some gas to get it to fire.

It idles fine now - unless you are at 0mph. You can be going along at 1mph, but once you come to a complete stop, it goes down to 200rpm and will eventually stall.

I have another 2000XJ I can swap parts from, but don't want to do it blind if you guys have an idea on what I should zero in on.

[jneary]

sounds like the pcm lost its memory from the dead battery. just statr it and keep it running, slowly decreasing the idle ant it should relearn

[JeepsterXJ]

Alright, and if I sound all antsy about a simple problem, its because I'm going to drive this 5 hours tomorrow in this is bad timing for an issue!

[jneary]

it should be ok, if it was fine before the battery was replaced

[JeepsterXJ]

Thanks jneary. I put my spare ECU from off the shelf. No issue (except the CEL turned on, I assume from the foreign computer). Put in old computer. Light goes out, idles, take a test drive, all fine. Thing was just messing with me I guess.

[bmfm64]

put a full charge on the battery... low battery messes with sensors and such.

[birchlakeXJ]

What you describe could easily be a marginal battery. Have it load tested. It's the only conclusive way to deteremine battery condition.