I'm having issues with my 2000 Tahoe 5.3 idling at 500 when warm and about 550 when cold. Activating the AC does not change the idle RPM. Chevy says all readings are within range after cleaning the EGR and replacing the MAF. The MAP sensor tested within range, a new IAC was installed, and new intake manifold gaskets were installed when swapping the engine last month. The fuel pump was also replaced less than 35k miles ago.
The truck also wouldn't start without assistance from depressing the accelerator pedal. A mechanic replaced the fuel filter and stated that it dispelled "black" fuel when disconnected. This did not resolve the idle or start up issues, so I took the fuel pressure regulator off the swapper engine's fuel rail and installed it. This resolved the start up issues but not the low idle and shudder. I've ran fuel system cleaner through it several times and Seafoamed it tonight via the brake booster vacuum. What would cause "black" fuel and failure of the fuel pressure regulator? Obviously the fuel injectors could be screwed as well and cause the present issues if clogged. Any suggestions for cleaning?
I know I have an issue with the Evaporation Emission Canister Purge Solenoid which likes to make a loud tapping noise. There is no vacuum leak (The intake manifold was smoke tested). I'm debating on whether it's lack of needed voltage reaching the solenoid. (Solenoids generally do the tapping sound when there's a lack of voltage). I'm reading 11.85 volts when connecting into the unplugged harness with the key in the ON position. I can't find specs on this thing for comparison purposes and would appreciate some help.
Also, my TPS is reading .667 volts at idle and no short circuit reading when testing ohms. Is that a normal DC range for idle? (I have a small blip at the 2 volt range when cycling the accelerator anyway but I'm trying to figure out my idle issues before plucking and chucking various parts.)
Thanks for the help.
*Sorry for writing a book, but it is what it is.
The truck also wouldn't start without assistance from depressing the accelerator pedal. A mechanic replaced the fuel filter and stated that it dispelled "black" fuel when disconnected. This did not resolve the idle or start up issues, so I took the fuel pressure regulator off the swapper engine's fuel rail and installed it. This resolved the start up issues but not the low idle and shudder. I've ran fuel system cleaner through it several times and Seafoamed it tonight via the brake booster vacuum. What would cause "black" fuel and failure of the fuel pressure regulator? Obviously the fuel injectors could be screwed as well and cause the present issues if clogged. Any suggestions for cleaning?
I know I have an issue with the Evaporation Emission Canister Purge Solenoid which likes to make a loud tapping noise. There is no vacuum leak (The intake manifold was smoke tested). I'm debating on whether it's lack of needed voltage reaching the solenoid. (Solenoids generally do the tapping sound when there's a lack of voltage). I'm reading 11.85 volts when connecting into the unplugged harness with the key in the ON position. I can't find specs on this thing for comparison purposes and would appreciate some help.
Also, my TPS is reading .667 volts at idle and no short circuit reading when testing ohms. Is that a normal DC range for idle? (I have a small blip at the 2 volt range when cycling the accelerator anyway but I'm trying to figure out my idle issues before plucking and chucking various parts.)
Thanks for the help.
*Sorry for writing a book, but it is what it is.
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