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2009 e350 sport
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214 Posts
Discussion Starter #1
..This after the intake manifold was changed to a new one.
History: The first check engine light was for a p2237. So I thought the bank 1 sensor 1 ( pre cat ) was bad so I installed a new one. That did not solve the situation. At that time I ate my humble pie and gave the car to an independent who further diagnosed the issue to be broken or frozen levers for the intake swirl valves in the intake manifold. That repair took care of the check engine light. After a week or so of driving around the CE light came on for a code p0040 indicating that Sensor 1 on both banks were swapped. I for one thought that impossible due to the different sizes and actual physical layout of the connection at the bottom end of the car. It also appears that at the top end connections are correct. I proceeded to REinstall the oxygen sensor for the pre cat bank 1 that I had taken out. Now after this I am getting a code p0300 for random misfire. Both STFT and LTFT for Bank 2 were maxed out(25+) when looked at the freeze frame data. The car idles rough , needless to say and the live data shows bank 2 going into OL ( open loop) . I renewed the spark plugs with the same Bosch plugs( it was time anyways , 11 years and 85k miles) and when I looked at all the plugs for bank 2 , ALL THREE were black and sooty looking compared to bank 1 which was light brown( normal?) in colour. I am not getting a P0174 for lean condition in bank 2 , nor a P0171 for bank 1. The oxygen sensors voltages "appear" to be fine for bank 1 but I am suspicious of those for bank 2.
Any insight to what you think might be going on here? I plan on taking back the car to shop that did the repair for the intake manifold. I know their scan tool can go deeper than my scan tool which is more generic.
 

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Registered
2009 e350 sport
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214 Posts
Discussion Starter #2
So I Took the car to my Indy( P0300 code) and he said three coil packs were bad. For reliability sake I had him install six new ones and he says all is fine now. I will see when I pick it up in the morning.
 

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Registered
2009 e350 sport
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214 Posts
Discussion Starter #3
I got back the car today and the car is running well. In addition to the six new coils both pre cat ( upstream / B1S1, B2S1) oxygen sensors were renewed. Prior to this repair I had installed six new spark plugs.
 
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