THE “FAILING” INJECTOR MYTH
It’s one of those experiences that diesel owners prefer to avoid. Having to choose between an expensive repair or operating at impaired efficiency. A diagnosis of a “failing” injector can total thousands of dollars in replacement costs. However, a closer look at the problem reveals an interesting insight.
Oil is exposed to temperatures much higher than reported on your engine temperature gauge. With enough heat and friction, the oil breaks down and leaves a gummy residue on the inside of the injector. This “gumminess” can cause a slight hesitation in the piston or spring release which can cause a diagnosis computer to trigger a “failed injector” code. This gummy, sticky, friction is called stiction.
More times than not, mechanics will suggest replacing the injectors after the failure code is triggered. This is where the myth comes into play. While it is true that a replacement will solve the problem of a HEUI injector not performing correctly due to stiction, it is often unnecessary. Why replace an injector that is designed to go 1,000,000 miles? The elements of an injector are well crafted and can perform for the life of the engine. It is the stiction that is causing the failure, not the malfunctioning of the injector elements. Thus the “failing” injector myth.
While many drivers prefer fuel additives to improve performance, the stiction build up that is causing an injector to fail requires a deep cleaning oil additive. This is often counter-intuitive to diesel owners who only consider the injector to be part of the fuel system, not the oil system.
Common symptoms of stiction begin to occur well before your mechanic runs the diagnostics on your engine. If you are experiencing hard starts, especially on cold mornings, stiction might be starting to build up. If your diesel hesitates to accelerate, has been losing its power, or you have been noticing a decrease in fuel economy, you could very well be facing a stiction problem.
CHRIS GABRELCIK is certified with STLE as a CLS and OMA. He personally developed and tested a product designed to remove stiction called Hot Shot’s Secret Stiction Eliminator.