westoverc1

Background:

99 mustang GT 4.6 SOHC windsor approx 90K miles.

Broke a connecting rod in #2 cylinder.
Removed engine including wiring harness three months ago.
Had #2 cylinder sleaved
Had block decked.
Had new valve installed, including new valve seals at machine shop.
Replaced #2 piston and connecting rod as well as additional connecting rod in #8 cylinder.
All new main and rod bearings.
New clutch.

My mechanic is a friend who is an ASE certified master tech from a dealer I worked at.

So we finally get everthing back together and drop the motor in and I originally got a P0355 code so I replaced the COP and still got check engine light. My mechanic originally thought it was a loose connection so I brought it to him today for a check. Upon examination he realized that it was not a short in the #5 COP. We ran a diagnostic (asked me to tap the break, turn the wheel, that sort of thing) using his code reader computer thing and it threw the following codes:

P0131 Upstream Heated Oxygen Sensor circuit out of range - Bank No. 1
P0151 Upstream Heated Oxygen Sensor circuit out of range - Bank No. 2.
P0171 System Too Lean - Bank No. 1.
P0174 System Too Lean - Bank No. 2.

It also seems (according to my mechanic) that the #1 COP isn't getting a signal. His thought was possibly because of bad ground or something like that. He's going to do some research on what those issues have in common but until then I thought I would throw this out there.

The car has a rough idle and lacks power.

Thanks in advance for any feedback.