bull30

I've been getting the P1145 code on my 2003 996tt. I erase the fault and it comes back about every 3 days. Yesterday I also got a P0135 code for the 1st time at the same time as the P1145. I have attached a pic of the FRA & RKAT readings but need someone with experience to interpret.

Macster

P1145 - Oxygen Sensor Ahead of TWC, Bank 1 - Above Limit

P0135 - Oxygen Sensor Heater in front of TWC, Bank 1.

I can't recall if it was a P0135 or a P0134 my 2003 Turbo was triggering on a drive back from the mid-west in Jan. of 2015 but when I got back home I had all 4 sensors replaced.

Not only did the engine run a bit better the error code was gone. Might add the times the CEL came on with the error code the engine never manifested any untoward behavior.

P1145 is a bit tricky... That it shows up after some few days is normal.

Possible fault causes:
Valve lift.
Exhaust leak affecting the O2 sensor after the TWC.
Oxygen sensor.

There is a pretty involved test to eliminate (or confirm) a valve lift fault is causing the code.

Have you modified the exhaust? Has the exhaust system been off the car recently? When it was last off were the metal turbo to exhaust manifold o-rings replaced?

Given you have the P0135 error code you might just throw 4 new sensors at both error codes. And of course, if there is any possibility of an exhaust leak address that too.

Carlo_Carrera

Could also be a cracked cam solenoid bracket on bank 2.