Lol I wasn't trying to find excuses. It's definitely an easy job. I sprayed around with throttle body cleaner and there was no change in idle.
I disconnected and re-connected the battery.
1. Day before: It was about 38F and the car ran fine over 8 miles of 45mph roads and freeways.
2. Yesterday: It was about 35-36F. It ran fine for a mile on the 45mph road, stumbled as I was merging onto the freeway, very minor stumbling when going from 55mph to 70mph. The car ran fine later when I was putzing around on 35-45mph roads and on the 4 miles freeway drive back home.
With the AMM plugged in, no error codes. With the AMM off, its 1-2-1. Does the B-cam/loping have anything to do with cold weather?
The car will be going into storage end of this week.
Here comes a long post.
The B cam loping has everything to do with the cold weather. It will always lump and sound like it has a fat cam anytime it's below maybe ~40F. It's nothing to worry about and sounds kind of neat IMO. At least that's the case with LH2.4.
Your symptoms actually remind me exactly of 2 failures I've had/seen of an in tank pump failure. When they fail, they are a huge restriction to the main pump and make it work wayyy harder. After driving for a few miles, depending on climate, vehicle, and main pump health, the car will begin to stumble. I have read people saying you can drive with a bad tank pump indefinitely, and that can be true.
Case 1: My 93 240 left me stumbling and stranded when I was in the high altitudes of Yellowstone as well as Denver, where fuel evaporates much more easily due to lower pressures.
Case 2: My 90 740 had a 100% seized in tank pump, and a noisy main pump. However, this car never showed any issues whatsoever! Needless to say I replaced both pumps and associated filters anyway.
Case 3: My buddy bought a 90 (91?) 740 turbo with a 'bad fuel pump' (they ALWAYS blame the main pump!) but I cycled the key 5 times and it came to life and drove us 1+ hrs before stumbling and dying. I'd let it sit for 5 minutes, then drive a few more miles, and finally it got bad enough to not start very easily. We believe the tank pump is dead in this vehicle. In order to get home, we installed the brand new Bosch main pump that came with the car and low and behold, it stumbled after 10 minutes of driving, but got us home and never died.
So to me it really seems dependent upon the vehicle. Sometimes you're lucky sometimes you're not.
Again I don't think it's likely that your car was just fine before mods and now isn't fine because of parts failure like the pump, but it's definitely worth checking to be sure.