Need help with P2187/P2189 and rough it idle
Thread Starter
Newbie
Joined: Aug 2015
Posts: 14
Likes: 1
From: Houston, TX
2006 ML350
Need help with P2187/P2189 and rough idle
I have an 06 ML350. Just over 100k miles.
I got the P2187/P2189 error for lean on bank 1.
I have recently replaced plugs and ignition coils. (Have been fighting misfires in various cylinders for about a year- comes and goes. Finally decided it was not plugs or ignition coils about the time I got these two errors above).
Found a cracked hose at front of filter housing. Replaced it
Also had a seal with a tear in it in the MAF where the filter housing fits. Replaced it.
Built a smoke generator to check for vacuum leaks. Found the two side flaps / ball sockets broken on the intake manifold and it leaking through both sides.
Replaced it, and gaskets.
I broke a stinking tab on the MAF putting it back on and replaced it (Bosch).
Now, the engine idles rough, but runs great when driving.
It popped the same two codes after a test drive tonight.
Also noticed if it was at idle and I pressed the accelerator, it would not lower back down on the rpms. I left it in the in position but not running a few minutes to reset the throttle / idle and that part went away.
Watching a scanner, the long term / short term fuel pressure is 25/0.
I do not have a pressure gauge to test on the rail, but can pick one up tomorrow.
Thoughts?
I can throw the smoke Gen. back in tomorrow and see if I find any other leaks. Short of that and the fuel pressure is there anything else I need to look at or test?
Any help is appreciated!
I got the P2187/P2189 error for lean on bank 1.
I have recently replaced plugs and ignition coils. (Have been fighting misfires in various cylinders for about a year- comes and goes. Finally decided it was not plugs or ignition coils about the time I got these two errors above).
Found a cracked hose at front of filter housing. Replaced it
Also had a seal with a tear in it in the MAF where the filter housing fits. Replaced it.
Built a smoke generator to check for vacuum leaks. Found the two side flaps / ball sockets broken on the intake manifold and it leaking through both sides.
Replaced it, and gaskets.
I broke a stinking tab on the MAF putting it back on and replaced it (Bosch).
Now, the engine idles rough, but runs great when driving.
It popped the same two codes after a test drive tonight.
Also noticed if it was at idle and I pressed the accelerator, it would not lower back down on the rpms. I left it in the in position but not running a few minutes to reset the throttle / idle and that part went away.
Watching a scanner, the long term / short term fuel pressure is 25/0.
I do not have a pressure gauge to test on the rail, but can pick one up tomorrow.
Thoughts?
I can throw the smoke Gen. back in tomorrow and see if I find any other leaks. Short of that and the fuel pressure is there anything else I need to look at or test?
Any help is appreciated!
Last edited by Keadlem; Jul 24, 2018 at 10:36 PM.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
The two codes you posted are not valid M/B codes. Whatever code reader you are using is converting the M/B code into their own code number.
Your problem is probably at the MAF Sensor, unmetered air entering the system.
You need a scanner to reveal the correct codes.
Your problem is probably at the MAF Sensor, unmetered air entering the system.
You need a scanner to reveal the correct codes.
Thread Starter
Newbie
Joined: Aug 2015
Posts: 14
Likes: 1
From: Houston, TX
2006 ML350
Hmm... I got the same codes on two scanners. Never had issues with accurate codes in the ML with either, but I guess it’s possible.
I downloaded the Carly app tonight that has MB specific diagnosis. It should give detailed codes. Will try it tomorrow.
The new MAF is a Bosch. What are the chances it is bad?
I downloaded the Carly app tonight that has MB specific diagnosis. It should give detailed codes. Will try it tomorrow.
The new MAF is a Bosch. What are the chances it is bad?
Thread Starter
Newbie
Joined: Aug 2015
Posts: 14
Likes: 1
From: Houston, TX
2006 ML350
Basically what I did- just with my version of the engine.
Everything seemed fine on the seals (MAF to throttle body connector, and seal for filter housing to MAF).
That said, the attachment to the throttle body (also held on with two plastic clips) seems flimsy. Baskets seem fine, but I would have expected it to be more solid than it feels. Everything seemed to go together fine though.
the MyCarly app gave a lot more detailed info than other scanners, but codes do not appear correct either.
Should I remove everything from the throttle body and put it back on to see if that clears anything up?
Anything else I should check? Thoughts are appreciated.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Whatever part you are referring to is what is causing the unmetered air to enter the intake system, as I suggested earlier.
