About 140 miles after this repair, I was merging onto a highway and the vehicle suddenly lost power under high load conditions. The CEL also came on. I managed to limp back to the shop and scanned the vehicle - this led to discovering the P061A22 and P000277 fault codes. After reviewing the freeze frame data and confirming that my low pressure fuel supply was adequate and within specs, I concluded that the high pressure fuel pump (HPFP) was not functioning correctly under certain conditions.
I was advised that this is not an uncommon issue with the M271 Evo engines. I ordered a replacement pump (reman) from a MB dealer (mbpartspros.com), a new clic-r collar clamp for the low pressure line and the 5 intake manifold gaskets. Supposedly, it is possible to perform this replacement without removing the intake manifold but it would be a major pain. The job bills out at 3.6 hr and since I am not feeling so lucky with this car, I took my sweet time and it took me about 4 hours to do the job.
Here are some pictures of the process:
a) Intake Manifold and HPFP removed:
b) Old Pump vs New (Reman) MB Pump. Note: I am aware that the end-piece of the old HPFP was still in the engine when I took this picture:
c) New (reman) HPFP installed, intake manifold still removed. It was a major pain to engage the clic-r collar clamp once the high-pressure line was already in place. I can't imagine how tough it would be to do this job without removing the manifold:
Between the cam adjuster repair, new spark plugs + ignition coils and this HPFP repair, I have over $2600 invested into getting this car to pass smog and be ready for sale. Can I interest anyone in a well-reconditioned C250?
I was advised that this is not an uncommon issue with the M271 Evo engines. I ordered a replacement pump (reman) from a MB dealer (mbpartspros.com), a new clic-r collar clamp for the low pressure line and the 5 intake manifold gaskets. Supposedly, it is possible to perform this replacement without removing the intake manifold but it would be a major pain. The job bills out at 3.6 hr and since I am not feeling so lucky with this car, I took my sweet time and it took me about 4 hours to do the job.
Here are some pictures of the process:
a) Intake Manifold and HPFP removed:
b) Old Pump vs New (Reman) MB Pump. Note: I am aware that the end-piece of the old HPFP was still in the engine when I took this picture:
c) New (reman) HPFP installed, intake manifold still removed. It was a major pain to engage the clic-r collar clamp once the high-pressure line was already in place. I can't imagine how tough it would be to do this job without removing the manifold:
Between the cam adjuster repair, new spark plugs + ignition coils and this HPFP repair, I have over $2600 invested into getting this car to pass smog and be ready for sale. Can I interest anyone in a well-reconditioned C250?
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