Fault Codes P2187 and P2189
07-04-2012, 05:29 PM
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2006 C230 Sport
Fault Codes P2187 and P2189
So, I have been dealing with this issue for some time where the car drives like gold for a week or so then starts with the intermittent rough idle, and the CEL comes on after setting P2187 and P2189. This all started when I got the car back from the dealership a few months ago (see my Perfect Storm post).
These codes are usually attributed to a bad MAF sensor if the fuel pressure is good. If the fuel pressure is high then its usually a bad fuel pressure regulator, which in my case means a 250.00 - 450.00 fuel pump assembly since my car has a unitized pump, sending unit, filter, and a non-serviceable fuel pressure regulator all wrapped up into one component inside my fuel tank.
Anyhow, I went to pop off the engine cover, and noticed that the MAF wasn't fully seated in the air box, but didn't think much of it.
I checked the fuel pressure and it was at 380kpa (54.9xx psi) which I have gathered is at the high end of the specification (330kpa - 380kpa). So I went and bought a mass airflow sensor, plugs, and coil boots. I am sort of old school when it comes to maintenance, so I started with the tune up. I popped off the coils and no. 6 coil boot was fried... and I mean fried! It was burned up. I pulled the plug out only to discover that it was loose in the head - no ratchet needed to extract the plug.
Upon inspection, I noticed that the ground side of the electrode was completely missing.
I pulled the rest of the plugs without incident, and everything else looks fine. So I finished the tune up, reset the codes, slapped the car back together, and test drove it before installing the MAF sensor. The car is driving better than ever. The CEL is staying out for now, and I am beginning to wonder if the combination of broken plug, bad coil boot, and faulty air box installation was setting these codes as phantom codes.
I think I am going to drive it for a week to see if the CEL comes back on - I'll post my results here. I checked with Carquest and they have assured me that that special order MAF sensor was returnable without a restocking fee. Those guys are awesome...
These codes are usually attributed to a bad MAF sensor if the fuel pressure is good. If the fuel pressure is high then its usually a bad fuel pressure regulator, which in my case means a 250.00 - 450.00 fuel pump assembly since my car has a unitized pump, sending unit, filter, and a non-serviceable fuel pressure regulator all wrapped up into one component inside my fuel tank.
Anyhow, I went to pop off the engine cover, and noticed that the MAF wasn't fully seated in the air box, but didn't think much of it.
I checked the fuel pressure and it was at 380kpa (54.9xx psi) which I have gathered is at the high end of the specification (330kpa - 380kpa). So I went and bought a mass airflow sensor, plugs, and coil boots. I am sort of old school when it comes to maintenance, so I started with the tune up. I popped off the coils and no. 6 coil boot was fried... and I mean fried! It was burned up. I pulled the plug out only to discover that it was loose in the head - no ratchet needed to extract the plug.
Upon inspection, I noticed that the ground side of the electrode was completely missing.
I pulled the rest of the plugs without incident, and everything else looks fine. So I finished the tune up, reset the codes, slapped the car back together, and test drove it before installing the MAF sensor. The car is driving better than ever. The CEL is staying out for now, and I am beginning to wonder if the combination of broken plug, bad coil boot, and faulty air box installation was setting these codes as phantom codes.
I think I am going to drive it for a week to see if the CEL comes back on - I'll post my results here. I checked with Carquest and they have assured me that that special order MAF sensor was returnable without a restocking fee. Those guys are awesome...
04-16-2014, 08:00 AM
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2006 C230 Sport
I know this is an old post...but I have a 2006 C230 Sport and have been popping P2187 and P2189.
I have replaced the MAF Sensor (Bosch) and replaced the Fuel Filter (KL82).
I have only put on about 30 miles on the engine with the codes gone however, I feel I haven't put enough mileage on the engine to see if these codes reappear.
The issue I still have though is that the engine has intermittent rough idle.
The plugs have been changed out about 6 months ago where I too had one of my plugs with a missing electrode.
Curious if you fixed your issues. As well, I've read there could be an issue with my intake manifold...? How would anyone diagnose if they have an issue with their intake manifold.
I have replaced the MAF Sensor (Bosch) and replaced the Fuel Filter (KL82).
I have only put on about 30 miles on the engine with the codes gone however, I feel I haven't put enough mileage on the engine to see if these codes reappear.
The issue I still have though is that the engine has intermittent rough idle.
The plugs have been changed out about 6 months ago where I too had one of my plugs with a missing electrode.
Curious if you fixed your issues. As well, I've read there could be an issue with my intake manifold...? How would anyone diagnose if they have an issue with their intake manifold.
