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Misfire in multiple cylinders, need advice.

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Old 04-18-2023, 03:58 PM
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Default Misfire in multiple cylinders, need advice.

Hello hope y'all are having a good day. My car is a 2004 Allroad with 2.7t and 138,000 miles. I am at least the third owner, and from what I know, it has k04, tune, egr and pcv delete (no catch can, the pcv breathers are just open). I am good friends with the previous owners cousin, but while it is not impossible to get new info, it is not happening as fast I'd like. I've put about 2,000 miles on since buying it and have done the oil change along with the passenger side valve cover gasket. I don't know of the maintenance history beyond that and I plan on doing the timing belt, water pump, and thermostat this weekend.

I drove it around a couple days ago for about an hour and then another hour the next morning. I had the heater and heated seats turned all the way up (was cutting weight for a bjj tournament). I went to the store and the car sat for about 15-20 minutes. When I started it back up, it sounded like a v8 and smelled like unburnt gas, there was also some slight white smoke. I got it towed home and pulled codes. It came up with p0036, p0056, p0300, p0301, p0302, p0304, and p0306. It had an intermittent check engine light, but I was told that this was because of the egr delete. I then cleaned the maf and ran it without a filter which did nothing. I pulled the cylinder 2 spark plug which had a black tip and smelled like gas. I smelled the dipstick, oil cap, and inside where the oil cap goes, which all smelled like gas as well.

Has anyone else had similar problems? Any help or advice would be very well appreciated.
Old 05-31-2023, 03:23 AM
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Pull all plugs and if they all smell gassy then u have fuel but not spark or intermittent spark causing the miss. If u are getting misses for all cylinders I would start by checking the plugs and coils are firing 1st. Then if you have a compression tester while the plugs are out check compression this will tell u right off if the motor is dead or still good. If all good with compression I would move to looking at timing possibly jumped a tooth. Then I would look at ecm pulse to make sure the spark is firing at the correct time but this will play into timing as well.

This is the basics as far as tunes and deletes I tend to stay away from cars that have been moded due to what the PO did and not knowing what was all done.
Old 05-31-2023, 03:27 AM
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U also stated white smoke in the tail. U may have blown a H.G try to boroscope the heads but then again the white smoke could also be from the unburnt gas as well. Start with the basics spark air fuel compression then work your way out to sensors wiring and things around it.
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