Midfield pair Ace Malo and Kameli Kuruyabaki were the dangermen, reserve hooker Joe Edwards was strong and winger Joseph Gilford scored a stunning individual five-pointer.
Despite flanker Cade Robinson being sinbinned for a late shoulder charge, Kaierau kept chancing their arm and when reserve forward Nemia Adrole palmed off two tacklers to score, they closed the gap to 31-26 with 14 minutes left.
Finally galvanised, Taihape immediately replied as Flaws went over in the far corner for his second try, then reserve Cyrus Paringatai and lock Johnson Hiroa scored off a good chip-and-chase and barge over maul respectively.
Kaierau coach Keith Savell was pleased his side showed heart and did not just give up.
"We asked them to show a bit of pride in the jersey at halftime, and they did that.
"But 30 minutes is not enough to win a game of rugby.
"They were flat when they started and line speed dropped away - we let them have easy yards."
With five regulars away, Taihape coach Kerry Whale was not happy with his team having another lapse in concentration. "That was our doing - we fell off. We put those four [Kaierau] players up on the whiteboard - we knew we had to look after them."
Having completed the first round with a 6-1 record and the only side to beat leaders Integrity Motors Pirates, Taihape are still in the strongest position this incarnation of the team has accomplished and Whale said they should kick on.
"This was about getting enough [competition] points - we've done okay with that.
"We move into the second phase so hopefully, the latter rounds, training takes us through these next couple of months."
After being under pressure from early penalties, Taihape got the ball through the hands and although passing was sometimes inaccurate, Flaws spied the gap and smashed through to score after 11 minutes. Getting back to the line, Taihape spread to each sideline, drew Kaierau in, and Transom jogged over untouched.
Gilbert and Iorns then combined like midfielders to put Transom over for this second.
Iorns was living out wide and after good follow-up from lock Hoani Woodhead, hooker Rimu Wipaki went through the gate at the tryline for 26-0.
The procession continued as Horton entered the backline and put winger Paora McCarthy over cleanly three minutes before the oranges.
But Kaierau came roaring back after halftime while Taihape suddenly couldn't get any traction with the ball, as the home side went wide from the scrum and fullback Hoani Pahl-Long slipped past returning reserve Luke Whale to score in the corner.
Malo, Joe Edwards, halfback Josh Edwards and then Malo again combined to get Kuruyabaki free to score just three minutes later, and then Taihape kicked out on the full to offer up another chance. Gilford got the ball with seemingly nothing on, yet pivoted back inside and found space, before going wide again and just running right through Taihape for a great solo try.
Despite losing ground, first-five Te Rui Wirihana linked with Malo and although it appeared Wirihana then passed the wrong way to his support, Adrole simply swatted away his tacklers for 31-26. Taihape immediately counter-attacked as Paringatai charged straight and Flaws followed up out wide to regain the impetus at 36-26 with 11 minutes left.
-PGG Wrightson/Ballance Taihape 46 (Taylor Transom 2, Jaye Flaws 2, Paora McCarthy, Rimu Wipaki, Cyrus Paringatai, Johnson Hiroa tries, Transom 3 con) bt Wanganui Car Centre Kaierau 26 (Hoani Pahl-Long, Kameli Kuruyabaki, Joseph Gifford, Nemia Adrole tries, Ace Malo 3 con). HT: 31-0.