I just finished redoing entire fuel system, which included all high, mid and low pressure hoses, new (to me) fuel pump and to top it all, Sea Foam flush of fule lines and injectors.
Long story short, car started right up, throttle response is excellent, idle is stable at 500 rpm, so new pump and cleaning helped a lot.
No funny part is rather distinctive clunk, coming from time to time from under the car. It can be hears frequently, but sometimes it would disappear for few seconds. It reminds me of loose flywheel bolt, catching block on my dad's X-Type. Exhaust is off right now and I think motor has a slight miss, after cleaning, so maybe it is occasional backfire, yet it sounds so metallic and crisp...I am lost, will investigate further tomorrow.

 

Check the transmission mount, they're notorious for going bad.

 

You mean the one in the rear? I checked it and it seems fine, hanging on spring, half way down. I will hook pipes back up and hear if it gets better. I doubt I could have damaged any motor internals by Sea Foam and by taking off and cleaning oil pan.

 

Turned out to be a backfire in the right bank. It cleared up after few starts.
I am still getting used to engine starting like new Honda and revving up in slit second!!! Damn, what a difference

P.S. some pics + junk I pulled.
P.P.S. just noticed that right side O2 sensor was unhooked and both motor mounts not bolted down... damn I am flaky or where!?