Hey Sidewall,
What do think may be the culprit of why there is intermittent start-up issues ?
Does the 6.0 liter engine have an "Oil Pressure Sensor Switch" to go bad. My old '95 6.5 turbo diesel had these fail often. The oil-pressure-sensor switch shuts off fuel in the event of a roll-over accident. May this be a possible culprit ?
I have a 2007 Chevy 2500 4x4 Suburban with the 6.0 engine. I have only owned it for 1-1/2 years, and put 30k on it in that time. I use it to haul my flatbed trailer and 16-foot Stock trailer. ( it is the 'wife's' car ) What I am concerned about with this engine is that I truly believe I need to find someone who can richen-up the fuel-air ratio.
What I am feeling is a "lean-miss" on a hard long pull up a grade on the expressway. I have taken it to the best shops in my area and both the GMC dealer and GM dealer.
They all keep telling me "all-is-OK" with my engine, but they are not "Feeling-It", and I wish there was a setting on the ECU where when I set my transmission to Tow-Haul mode, that would also richen the mixture to a richer setting to squelch the lean "stumble" which is aggravating.
I drove a -95 GMC 2500 4x4 Suburban with 6.5 Turbo Diesel for 15-years and the electronic injection-pump controller (PMD - pump-driver-module) goes bad and causes stumbling and stalling and all kind of codes to be thrown, which in my opinion is "default" stuff which may not identify the "culprit."
After installing my 3-rd PMD, for 3-years following, my cruise control was intermittent, and I kept getting a check-engine light which I ignored, because I kept getting a Injection Pump code thrown. (there is nothing to rebuilding a pump except new Seals). So I take the rig to the shops, and they want $4k to replace the injection pump. B.S. to that. I finally found that the "Injection-pump" Code being thrown, was because of a Vacuum leak in the waste-gate circuit !
Why couldn't the mechanics have told me this ? ….. I am just the Consumer with the "deep-pocket"
The demise of the vehicle is that the freeze plugs began rusting trough at 280k miles, and the shop wanted $4.4k dollars to pull the engine and replace all the freeze plugs. Just before selling the vehicle, I discovered that I had a leaking vacuum line fitting supplying vacuum to the Turbo waste-gate controller. The fitting looked tight, but leaked. After correcting the vacuum leak, the engine ran like brand new, and in a 500-mile journey, the cruise control never missed a beat, and the check-engine light never came on. Simple little things ……. that an engine analyzer won't tell you. This is why a good Diagnostic Techie is hard to find, when you must go beyond the Codes.
The odometer had 295k on it when I sold it. In the 15-years of ownership I faithfully ran Marvel Mystery oil in with the fuel to assist in lubing the injection-pump, and to also keep the Optical-Sensor clean inside the injection-pump. I never had a valve-cover off of that engine nor did I ever change injectors, or glow-plugs or injection-pump.
The engine oil consumption never changed in those 15-years either, and consumed 1-quart of oil in 400-miles. A Great work truck !
I have to laugh at myself when guys tell me how wonderful their fuel mileage is with their Super-Duty diesels. It is a proven fact that is takes "X" amount of fuel to build "X" amount of Horsepower. You just cannot get 19-miles per gallon driving a 7k lb pickup pulling a 9k lb trailer up into the 6k elevation from sea-level. hahaha
Al
