I replaced the alternator in the wife's 2002 Escape, and when it's cold, the idle is erratic for about a minute on start-up. This effects charging during this time, and the ABS light flashes on.

I disconnected the battery while I did the R&R, so it should have cleared everything, and I'm not getting any codes.

I haven't had the battery load tested yet, but there are no real signs of a bad cell.

It always starts right up, and after the initial "wavering", the idle smooths out, and the vehicle drives fine.

Any thoughts?

Thanks,

 

I presume this started right after the repair, but didn't do it prior? I doubt it's the alternator repair itself. You may have knocked something loose doing the fix. A vaccum line, the secondary air pump (if this car has one), or an O2 sensor wire.
Most of my cars idle or sound a bit wacky for the first 30-90 seconds on cold start. It's caused (on mine) by the air being injected into the exhaust by the SAI pump to pre-heat the CATS.
I think all modern cars have a system like this.

 

You cannot clear codes on an OBDII SYSTEM BY DISCONNECTING THE BATTERY.
What does happen when disconnecting the battery is the adaptive memory is lost and the vehicle has to be driven through some drive cycles to relearn . Be patient and it should clear up if there are no further problems.
Why did you need to replace the alternator?

 

Re: TMcNasty, if you're familiar with this repair, there are no other engine systems that are at risk with this procedure. The alternator is accessed by going in through the wheel well, pulling the splash shields, and ultimately the right side drive axle. If I was going to inadvertantly cause an issue, it'd be with the brakes, suspension, or drive. It's one of Ford's "better ideas".
Re: hanky, I wasn't trying to clear codes, but the adaptive memory. As I'm sure you know, this is a good idea any time one replaces a malfunctioning electrical or emissions piece.
I did the R&R back in November, and the issue has persisted when it was cold.
This is quite certainly not normal, and there is no reason to expect that it'll just clear up on its own.
Just an FYI, I maintain a minimum of 6 (mostly Ford) vehicles, from this Escape to a 7 series BMW and a Ford diesel van.
I've been wrenching since the late 60's, and worked at my Dad's Ford dealership back in the 70's, so I have a pretty good understanding of how these things work.
If this was a simple fix, I'd have it by now.
I'll also add that I do have a code reader, and the diagnostic know how, which is why I asked for input from someone who may have had the same experience.
Thanks for your input.

 

Just out of curiosity, what kind of data stream readings are you getting when cold, then warm/hot over 140 degrees or when the idle evens out?
You may find a clue to assist in your diagnosis.