Troubleshooting Diesel Engine Hard Starting, Low Power and Exhaust Smoke

Top problems for diesel owners. Kent recommends starting with the basics

What is wrong with my diesel engine? This technical question wins the grand prize! It is by far the most often asked question that we have received from our customers over the years. It can not be easily answered without some troubleshooting on your part.  Whether it is hard starting or shut down, rough running, excess smoking, poor power output, or poor mileage, often times it can be more than one of these things. More often than not it turns out to be a combination of maintenance neglect that has built up over the years.

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Problem & Solution

Common among these chassis:

W115
W116
W123
W124
W126
W201

What can you do? Here are 5 key things you can do to help you narrow down the source of your engine performance problems and fix them yourself. Do not be afraid to try. The reward could be the savings of hundreds, if not thousands of dollars!

We recommend that you follow the maintenance sequence in the order listed below. This will be help you narrow down the problem or problems you are having without wasting time or spending unnecessary money.

1: START WITH A BASIC ENGINE HEALTH CHECKUP
2: PROCEED TO REGULAR SERVICE WORK
3: PERFORM PRE-GLOW SYSTEM CHECK AND CLEANING AND PERFORMANCE MODIFICATIONS
4: MOVE ON TO INJECTION PUMP AND FUEL INJECTORS

If this is a diesel you have recently purchased or one that you have no maintenance records for, I would highly recommend that you begin your fuel injection troubleshooting by removing and inspecting the fuel injectors. This is not a difficult job - but BEFORE you begin you will need some essential tools and supplies on hand.

5: FINISH UP WITH ADVANCED TROUBLESHOOTING

We have so many resources to help you will diesel engine performance problems we can not list them all here. Use our solutions finder or refined search box to search for a solution to one problem at a time. You will be then able to find more specific information on your problem. 

!!!To watch PART 2 of this video please click here !!!