Problem relearning fuel tables?

[Dirmaid]

Ok, the other day I performed a tune up on my 01 ranger and since I have a remote start system I pulled the battery leads while I worked. When I hooked them back up, it cranked fine but idled a bit high (1100). Not really the issue but felt as if i should say it. I went for a test drive and all was fine. However, full throttle is extremely lean according to my wide band. I had my tune dialed in to 12.9-13.1 at WOT, but now I'm lucky to see as low as 13.9. On average it is showing around 14.2 at WOT and has no where near as much pull as it used to. It's kind of worrying since the only thing that changed was new plugs/wires and a disconnected battery. I drove it for a half tank thinking it only needed to relearn itself, but wot afr is still the same. Next step i took was a new tune. I added 5% fuel at wot, but i'm still showing extremely lean after 3/4 of a tank on the new tune. Part throttle (in this case 50-80%) is 12.5-12.9 though, but as soon as it gets to full it goes lean again. Also, the truck seems to randomly go rich while I'm driving perfectly sanely. Normal driving afr is still 14.7-14.8 but every now and then (i cant replicate it on demand) it will creep down to 14.2, then back up to 14.7.

Additional info: 2001 ranger 4.0 sohc, sniper tuner, using the same wideband for all runs, didn't touch anything that would affect afr during tune up.

Any help/suggestions would be helpful.

 

[adsm08]

I would start by getting the tune out, getting the program back to stock, and see how it does there. If the AFR stays normal with the factory program then you know you have a software issue. If it still does the same thing you have a truck issue.

 

[Dirmaid]

Alright, I put the stock tune back on and drove it around long enough to get the p1000 out of the system and its doing the same thing. I have noticed, however, that if i ease into full throttle it stays rich in open loop all the way to almost full throttle. once its at wot, it runs lean. I put the tuner on it to see if it was seeing wot and the first pull it maxed to 50%, but every time after that it saw 100% and was still lean

 

[Dirmaid]

Just incase someone else has this issue, the AFRs normalled back out, but it took about a full tank and of half of mixed driving conditions. I'm not sure why since the only thing it should need to relearn in fuel trims at low throttle, but hey it works now.