2012 E550 misfire? P219F code?
03-30-2019, 03:26 PM
#1
Newbie
Thread Starter
2012 E550 misfire? P219F code?
My car has a tune and it has been driving perfectly for years. Well first problem. P219F code and slight feel of misfire and smell of fuel at idle.
My code scanner is pretty basic but it looks like a fuel trim issue from bank 1 to bank 2, but bank 1 looking like it is the problem.
I bought enough spark plugs to change the passenger side which apparently is bank 1. The old plugs were black, new plugs didnt help.
Do these cars have MAF sensor(s)? If anyone knows where they are, I will try to clean them, I couldnt find them or ANY info online.
HELP! Thank you for reading.
W212 4.6 turbo 550 tt
My code scanner is pretty basic but it looks like a fuel trim issue from bank 1 to bank 2, but bank 1 looking like it is the problem.
I bought enough spark plugs to change the passenger side which apparently is bank 1. The old plugs were black, new plugs didnt help.
Do these cars have MAF sensor(s)? If anyone knows where they are, I will try to clean them, I couldnt find them or ANY info online.
HELP! Thank you for reading.
W212 4.6 turbo 550 tt
03-31-2019, 08:17 PM
#2
MBWorld Fanatic!
I looked up that code and it seemed to relate to an imbalance related to #4 cyl. so that correlates with your comment about B1 fuel trims. But you didn't post what the real time run data was, STFT/LTFT, O2, TPS, MAP/MAF etc. as read in closed loop, or what the freeze frame data was.
Just thinking out loud....
That cylinder misfire related to fuel, spark or compression, so the logical recourse is to try to verify each, starting with the basics. If all plugs are black then the ECU is seeing high LTFT readings and adding fuel - too much fuel. Or if there is a timing or compression issue, the ECU is trying to compensate and cannot do so within range.
First, do a careful visual check, you never know what you may come across. May be something very simple.
Ensure the air cleaner is fitting ok: https://mbworld.org/forums/e-class-w...ug-change.html
What do the fuel trims do at idle vs 2500 rpm? If they even out (ideal is generally 0-3%) at higher rpm, that can indicate a vacuum leak, so then the next step is to check air cleaner, all hoses, etc. You need to really poke around those hoses to ensure there's not a crack somewhere or a broken hose.
I think on your car the MAF is located on the rear of the engine, right on the throttle body elbow. This is on my V6 but the MAF should look the same:
https://mbworld.org/forums/e-class-w...-cleaning.html
I'm kind of doubtful from the code that it's a single coil but you can swap #4 coil with another cylinder and see if the trouble code number changes or remains the same.
You can also ohm the #4 fuel injector to check resistance or an open (shorted) injector coil - offhand I don't remember the correct range, but you can ohm all injectors on that bank and compare the readings. They should all be very close. Remove each injector plug and then connect an ohmmeter to each terminal on the injector. You can check engine run voltage pulses to the injectors with either a noid light of some sort or a voltmeter probed into the control wire to the injector (probed at the connector). You want to verify that the injector(s) are each getting control from the ECM so that they are working. I like an oscilloscope for this because a voltmeter can have a hard time indicating control pulses in milliseconds. But noid lights are available or you can make your own which is what I have done. Just simple LED light that can be attached to the injector connector.
You can check relative compression but I don't think you have an amp clamp or oscilloscope, so you can use standard method of using a compression gauge. Remove the fuel pump fuse and crank the engine with throttle wide open. I'm thinking it should be in the 150-170 psi range but again, you can check compression on that bank - all cylinders should all be within 10% or so of each other.
The code also relates to crank and cam position sensor readings but for this you would need either a better scantool or an oscilloscope to compare readings of each sensor. I think though that you would see a different code in addition to the P219 code.
Don't overlook the O2 sensor readings - they are wideband so that voltage should be in the 2-2.5v range. Narrowband O2 switch constantly between 0-1v. Bad readings will throw off STFT, then LTFT which will throw a code.
That's a start I guess. I'm not a turbo guy - I know how they work and are connected but there may be additional diagnostics related to the turbo side of the street.
I am a proponent of making a moderate investment in diagnostic tools that can help you learn about how things work and avoid shop time and cost where reasonably possible.
Just thinking out loud....
That cylinder misfire related to fuel, spark or compression, so the logical recourse is to try to verify each, starting with the basics. If all plugs are black then the ECU is seeing high LTFT readings and adding fuel - too much fuel. Or if there is a timing or compression issue, the ECU is trying to compensate and cannot do so within range.
First, do a careful visual check, you never know what you may come across. May be something very simple.
Ensure the air cleaner is fitting ok: https://mbworld.org/forums/e-class-w...ug-change.html
What do the fuel trims do at idle vs 2500 rpm? If they even out (ideal is generally 0-3%) at higher rpm, that can indicate a vacuum leak, so then the next step is to check air cleaner, all hoses, etc. You need to really poke around those hoses to ensure there's not a crack somewhere or a broken hose.
I think on your car the MAF is located on the rear of the engine, right on the throttle body elbow. This is on my V6 but the MAF should look the same:
https://mbworld.org/forums/e-class-w...-cleaning.html
I'm kind of doubtful from the code that it's a single coil but you can swap #4 coil with another cylinder and see if the trouble code number changes or remains the same.
You can also ohm the #4 fuel injector to check resistance or an open (shorted) injector coil - offhand I don't remember the correct range, but you can ohm all injectors on that bank and compare the readings. They should all be very close. Remove each injector plug and then connect an ohmmeter to each terminal on the injector. You can check engine run voltage pulses to the injectors with either a noid light of some sort or a voltmeter probed into the control wire to the injector (probed at the connector). You want to verify that the injector(s) are each getting control from the ECM so that they are working. I like an oscilloscope for this because a voltmeter can have a hard time indicating control pulses in milliseconds. But noid lights are available or you can make your own which is what I have done. Just simple LED light that can be attached to the injector connector.
You can check relative compression but I don't think you have an amp clamp or oscilloscope, so you can use standard method of using a compression gauge. Remove the fuel pump fuse and crank the engine with throttle wide open. I'm thinking it should be in the 150-170 psi range but again, you can check compression on that bank - all cylinders should all be within 10% or so of each other.
The code also relates to crank and cam position sensor readings but for this you would need either a better scantool or an oscilloscope to compare readings of each sensor. I think though that you would see a different code in addition to the P219 code.
Don't overlook the O2 sensor readings - they are wideband so that voltage should be in the 2-2.5v range. Narrowband O2 switch constantly between 0-1v. Bad readings will throw off STFT, then LTFT which will throw a code.
That's a start I guess. I'm not a turbo guy - I know how they work and are connected but there may be additional diagnostics related to the turbo side of the street.
I am a proponent of making a moderate investment in diagnostic tools that can help you learn about how things work and avoid shop time and cost where reasonably possible.
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Johnny Rad (03-31-2019)
04-01-2019, 07:55 AM
#3
Newbie
Thread Starter
Thank you for the reply.
Update, since it was a bank1 rich error, I got my hands on a limited scanner and it wouldnt show me primary o2 sensor signal, but it would show me the secondary o2 which was rich. So I unplugged the primary o2 sensor and the fuel trims went to zero and the car started running good again. So I am assuming I have a bad primary o2 sensor. So I will order one up and see what happens.
Update, since it was a bank1 rich error, I got my hands on a limited scanner and it wouldnt show me primary o2 sensor signal, but it would show me the secondary o2 which was rich. So I unplugged the primary o2 sensor and the fuel trims went to zero and the car started running good again. So I am assuming I have a bad primary o2 sensor. So I will order one up and see what happens.
04-01-2019, 09:31 AM
#4
MBWorld Fanatic!
Sounds like an easy fix, good deal.
I would suggest checking voltage at the connector to the O2 to verify bad sensor or possible wiring issue before getting a new sensor. But on the average it seems the sensor is at fault.
I would suggest checking voltage at the connector to the O2 to verify bad sensor or possible wiring issue before getting a new sensor. But on the average it seems the sensor is at fault.
