[[FIXED]]
Hey guys,
On my way to work the other day my 325i started sputtering while at a red light, once I crossed the street it died. I was able to limp it to a parking lot while it died a few more times. It clearly was misfiring so I started with spark plugs, once I changed them I noticed a bit of oil in two of them so I replaced the VCG. I got a code reader today and was shocked with how many errors came up. I'm sure they go hand in hand but heres what I got.
P0300- Multiple cylinder misfires
P1083- Fuel control mixture lean
P1349- Misfire cylinder 4 w/ fuel cut-off
P1351- Misfire cylinder 5 w/ fuel cut-off and ignition coil control circuit high voltage
P0171- System too lean bank 1
P0185- Fuel temp sensor b circuit malfunction
P0174- System too lean bank 2
Pending:
P1346- Misfire during start cylinder 3
After some research I figured I would first start checking for vacuum leaks.
Has anyone ever had similar issues? All of these happened at once, at least I think they did. I never had any problems with the car before. 150xxx miles.
Thanks
Update: Got the car home, rough idle dies when given power... Going to change the fuel filter next.
Solution: Upper intake boot had two major cracks, once replaced idling issue was still there. I noticed the car ran fine with the MAF unplugged, which narrowed it down for me. Replaced the MAF and we are back to running normally. Also, cleaned the ICV which may or may not have helped (who cares), it's clean now.
Last edited by ncolfer; 04-10-2018 at 08:47 PM.
You have multiple misfires, probably caused by lean fuel mixture conditions present in both banks 1&2.
I agree on the most possible cause to be an intake leak/vacuum leak.
Since it happened so suddenly, remove rubber intake boot,
squeeze and check it for hidden cracks, along with all associated hoses.
If nothing found, then a smoke test with a professional smoke machine should be performed.
Post back with what you find.
Yes,
exactly, so what is his fix-according to his diagnosis?
Btw,
Not to hurt feelings, but your friends advice totally contradicts the computers.
Clear ALL codes, then take note of new ones that reappear, after a short drive cycle.
Cleared codes, drove... they reappeared. Still haven’t gotten the correct FF. Took the ICV off today and it was making noises like it should, cleaned it anyway. There was two big cracks in my upper intake boot. Ordered a new one. Hoping that helps a bit, I don’t think it will fix everything though.
You sure are headed in the right direction for a correct diagnosis and fix,
once you replace those critical parts. Finding those cracks in the rubber boot was great,
you actually done much better than yourknowledgeable friend...lol.
Replaced the upper intake boot today, reset codes, turned it on and it ran fine no issues. Go check the engine and realize I forgot to plug the MAF back in. Plug it in... back to a bad idle.. looks like I found the problem. I'll be headed the the junkyard this week to pick up a "new" one. FF is still on it's way.
I still have some codes left to figure out,
Confirmed:
P1083 Fuel Control Mixture Lean (Bank 1 Sensor 1)
P0171 System too Lean (Bank 1)
P0174 System too Lean (Bank 2)
P0185 Fuel Temperature Sensor B Circuit Malfunction
Pending:
P1346 Misfire During Start Cylinder 3
P1351 Misfire Cylinder 5 With Fuel Cut-off
Once new boot installed,clear codes.
Lean codes should not reappear,
unless FF is obstructing fuel flow.
Or you can wait until boots and FF have been replaced
The engine computer (DME in BMWspeak) runs an overly rich fuel/air mix when the MAF is unplugged. That masks vacuum leaks. Have the intake smoke tested.
If the upper boot was broken chances are that the lower boot is also broken. The lower intake boot usually goes before the upper. Unplugging the maf makes it run better. This is a symptom of an air leak, usually the lower boot. Replacing the maf will probably not help. I would not replace the maf until you have checked the lower boot. It usually cracks on the small branch that connects to the idle control valve. If the boots are good, do a smoke test.
Sent from my SAMSUNG-SM-G870A using Tapatalk
Randy,
Thanks for the reply, when I took my ICV off to clean it I checked the lower boot and it was crack free. After I put everything back together and the realized the ICV wasn't the issue, I left the MAF unplugged and the car ran fine (no issues with idling) I just figured it was time to replace it. New MAF arrived today and everything is back to normal!
Bookmarks