MDEP Highlights

November 25, 2009 

Today’s MDEP Highlight demonstrates how the MDEP process can be used to diagnose a problem that may otherwise have never been found or corrected. Today’s example comes from a 2000 model year electronically controlled engine. In this case, a baseline MDEP evaluation was performed on the engine and the following recommendations were made.

“Evaluation results indicate the engine is injecting 'way' more fuel than it can burn during engine acceleration. The five gas results indicate lower than normal Nox and increased Hydrocarbon recorded during the last engine idle at 80 through 100 seconds in the five gas procedure. Recommend replacing the turbo boost sensor followed by conducting an engine diagnostic check. Recommend Installing C-Max to reduce DPM and fuel loss. “

The recommendations included “conducting an engine diagnostic check” indicating a suspicion of improper settings within the engines computer control module as well as over fueling. Action was taken to follow up with the recommendations on this engine. A mechanic was able to examine the engines computer control software and determined the software was designed for an engine with primed injection. This engine however did not have primed injection. The engines computer control software was changed to the proper version. Changing the software to the correct version dropped the DPM from 95.2% to roughly 50%. This was then followed by the installation of a C-Max unit to result in a further reduction of DPM from the 50% range to 18.8%.

Overall, this engine was able to reduce its emissions from thick black smoke at 95.2% DPM levels to barely visible levels of smoke of 18.8%. Without direction from the MDEP procedure to examine the engines computer control software the improper software version may never have been discovered resulting in poor combustion efficiency and increased emissions over the life of the engine. Increased combustion efficiency resulted in a savings of 2,800 gallons of fuel per year and a reduction of 990 pounds of DPM emitted into the environment each year.

Baseline Evaluations (Before C-Max)

Current Evaluations (After C-Max)