Temp issue on new motor?
 

I had posted about installing a rebuilt to 3.6 LN block into my car. I thought I had all the bases covered. New 170 degree stat, new pump, improved engine compartment fan, Center Front radiator, new hoses. This week end we had the first temp over ninety. In a twenty minute traffic drive the engine temp was over 200 sitting in traffic, easily 1/2 way between 180 and 225 lines on the gauge out side air was 98. Maybe this is normal but I've never had a temp more than a line thickness over the 180 mark.

It gets worse, on the way home I threw a P2098 code. Bank 2 sensor 2 lean trim mix.
Snap shot
Bank 1 sensor 1, 15%
Bank 2 sensor 1, 14.7%
Bank 1 sensor 2, 5%
Bank 2 sensor 2 -3.1%
water temp 198
2980 RPM
Throttle actual 12%

Reset the code and checked the bank 2 sensor and cable with no real issue. I ran 50 miles the next afternoon in 95 degree temp no traffic I had a couple of times were there was a hesitation but it did not set a code . I ran 75 mile this morning. Cooler in traffic and the temp outside was only 80. No hesitation no code still.

Do I have a temperature problems or a sensor failing? If its Temperature what do I do additionally That I already did not do.

You burped the coolant tank after the engine install? Checked that the radiator fans run at the right time?

Who did the ECU flash and did they have the engine with all its mods when they built it? The only guy I know who does this has a dyno and a programmer. He says it sometimes takes 2 months to get the settings right alternating between dyno runs, test settings and real world drives.

All radiators cleaned and intakes screened? AFR dyno tuned to make sure you are in the sweet spot across rev range? Larger 3.6 oil cooler?

Thats the only extra modification I did not do. I have the stock 3.2 cooler on top the engine I guess I'll need to remote an oil cooler as well. Thank for the reply.

Right now the new motor has 2800 miles on it I've have 3 track day and an AX. All driving in mild temps (70's)and this was the first in heavy traffic (90'S).

Would a bad O2 sensor cause a high engine temp Bank 2 sensor 2 is a flat line. I forgot that Dyno scan on my PC has scope functions. That sensor gives me about 2 sin waves when you burp the throttle then goes flat again. about .108 volts The trim is about 15% max. all the other are 5 to 60% .047 to .78 volts