Bank 1 Misfires; complete stall in 2-3 mins

[stuco]

2003 E53 M62 (170K miles)
Engine idles really rough for 2-3 minutes before completely stalling.

Background: I just replaced timing chain, guides and cover gaskets using 3 sources and meticously validated timing and torques. Car ran well for a week although a little lumpy at idle.

One morning on startup, it idled really rough, brakes are stiff to press and SES light is flashing. Grabbed the 5 codes which indicated multiple misfires with fuel shutoff on cylinders 1-4 (P0363, P1343, P1345, P1347, P1349). I have the Diagnostic Report and a couple of short-lived logs from OBDFusion available at the following Dropbox link:
https://www.dropbox.com/sh/44qzf65rb...9w43Ra8ja?dl=0

So far, have switched and replaced Cam Position Sensors, replaced all spark plugs and tried spraying MAF cleaner in common points (intake boot, throttle body, both intake manifold, vacuum hoses) with no apparent change. Have not done a smoke test yet, because I am curious why it's reporting codes only on 1 bank.

Thanks in advance for the help, I just don't want to throw any more $$$ at the problem with guesses.

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[andrewwynn]

Pull MAF plug and see if it will run smoothly. If you have a different similar car (friend etc) you can borrow MAF see if you can or even buy a cheap knock off for testing. My gut-o-meter is saying MAF


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[stuco]

Thanks for your reply. I knew that the MAF wiring from the connector to the engine wiring harness might have be suspect, because the outer shielding is cracked. Upon closer inspection, it appears that the wiring is intact, so short circuits can be ruled out.

I decided to clear the codes and unplug the MAF connector. Now the car cranks, but will not start (no new codes yet). Plugged the MAF back in - same result. Feverishly searching the forums; I don't know what I could have done to cause this new development.

New files in Dropbox if anyone's interested:
https://www.dropbox.com/sh/44qzf65rb...9w43Ra8ja?dl=0

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[bcredliner]

Good practice with auto repairs is there are no coincidences. Since you worked on it 3 weeks ago, exhaustingly check your work before branching out. Hopefully, it is not something internal coming loose. MAF would be a coincidence. However, MAF is easy to clean. Use MAF cleaner only and be sure to spray the wires that are not obvious. That said, bad MAF should show misfires on both banks.

[andrewwynn]

Somebody on xout recently had very very similar problems after a rebuild.

The end solution was he had intake and exhaust cam sensor plugs swapped.


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[upallnight]

Originally Posted by stuco

Thanks for your reply. I knew that the MAF wiring from the connector to the engine wiring harness might have be suspect, because the outer shielding is cracked. Upon closer inspection, it appears that the wiring is intact, so short circuits can be ruled out.

I decided to clear the codes and unplug the MAF connector. Now the car cranks, but will not start (no new codes yet). Plugged the MAF back in - same result. Feverishly searching the forums; I don't know what I could have done to cause this new development.

New files in Dropbox if anyone's interested:
https://www.dropbox.com/sh/44qzf65rb...9w43Ra8ja?dl=0

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Backyard mechanic trying to save some money by changing the timing chain himself with no experience in perform this service and most likely not having the correct tools to perform this service. I say start with that scenario and go from there.

You may also want to look at your intake air sensor. We're sitting at about 30C, you must be in the frozen Tundra to be seeing an intake air temp of -40C.