I’m in danger of surrendering my man-card fellas.
In the 30 years of ownership, I have officially been bamboozled by my 95 GMC K1500 4x4. After extensively researching my manual and possible causes of its poorly running issue, I am just plumb out of ideas. The next step in this mystery, is finding a way to test the back pressure via an insert I can run into my 02 sensor bung to attempt to detect a blocked or restricted catalytic converter. Two senior mechanics mentioned the symptoms sound like a blocked cat. Today, I loaded 20 gallons of fresh gas into the tank to test the Fuel Pump replacement job. The pump sounds 200% better and I am more confident that it won’t short and explode, but it still ran like garbage. There is no “check engine” lite
Work done since April 16th, 2024:
Rebuilt TBI unit with new injectors
New fuel pump
New fuel filter
New M.A.P. Sensor
New I.A.C.V.
New T.P.S.
New ignition control module on the distributor
New plugs
New cap
New rotor
New O2 sensor
New EGR valve
New EGR solenoid
No known vacuum leaks checked via the spray test.
New manifold temp sensor
New K&N air filter
I am out of ideas as is my shop manual ….
So I hit the six exhaust manifold bolts with PB Blaster to let them soak. It will be a miracle they don’t snap off. The theory is that by opening the exhaust system a little bit, if the cat is restricted, the gap will allow the engine to breath and run slightly better, although very loudly. [emoji2371]
I’m pulling at straws at this point.
I am open to any ideas or suggestions
Cheers
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