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Hi, I'm a new BMW owner. Just purchased a 325ci about three months ago and I've been working my way through getting all the error codes corrected. I have a very strange combination of error codes that appear in the computer every time I start the car. I've cleaned the idle air control, DISA and MAF and verified that these are not the problem. I've replaced the Themostat and it's housing with an official OEM, replaced one of the ignition coils and have moved the new one around to different locations, which doesn't change the codes. I'm wondering if a temperature sensor could be causing these errors, or perhaps I need to look somewhere that I'm not thinking of.

The codes come up in this order, I've been monitoring their order for some time.
First - I get P0174, P0171 and P1619 - so Bank 1 and Bank 2 System too lean, and the P1619 indicates a thermostat sensor or temp sensor.

If I don't immediately clear those then it will be followed by P1352, P1351, P1349 and sometimes P0161 (However I haven't seen the 0161 for a while)

P13xx - missfires for cylinders 6,5,4 in order
P0161 - O2 sensor bank 2 sensor 2 - but only sometimes and only if all the other errors are thrown and I don't clear the codes right away.

So I'm getting missfires after the thermo sensor and lean conditions, and the car will run rough I assume because the computer is trying to correct for the missfires. If I clear the codes then the car will immediately run perfect and I won't throw any more errors until the next time I turn the car off and start it back up again. And it doesn't matter if the car is cool, or at running temp... but pretty much every time I start the car, I have to clear the codes, and then I once drove it across the state, 150miles without turning it off, and it ran perfect the entire trip and only threw the codes again when I have to start the car after we stopped for lunch.

If I don't clear the codes the engine starts to sputter and drives rough, indicating that there's a very bad mixture of O2 and gas so it's running too rich causing the exhaust to backfire...

Any suggestions what my next step should be????
Temp sensor - or exhaust problem????
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