I have a 2000 yukon denali with the 5.7 vortec, that my dad stored outside for 5 years, I am trying to get it into running shape. When I first got it, I changed spark plugs and sprayed fogging oil into the cylinders, new battery, had to put in a new starter, checked the fluids, etc. At first it smoked a bit (most likely from the fogging oil), but now its good.
However I have a new problem, it is misfiring a lot on cylinders 1 and 7 (which are on opposite ends of the same bank). It vibrates alot. Its throwing P0300 and occasionally a specific cylinder code for cylinder 7 or 1. I used a spark tester, and cylinder 1 and 7 seem to be getting spark normally, inspected the new spark plugs and confirmed they are ok, checked fuel pressure, and according to the obd2 data the vacuum level is normal.
I am going to do a compression test next but I think that maybe the valves are stuck or sticky, because i'm not sure what else it could be.
One other peculiarity is that when I turn the key to the run position the fuel pump never shuts off, I have replaced the relay and it still does this. Not sure if it is related however. I am also getting a weird reading from the sensor TID: $07 CID:$0d in torque pro which gives a current voltage of 56,320 and a max of 197.
However I have a new problem, it is misfiring a lot on cylinders 1 and 7 (which are on opposite ends of the same bank). It vibrates alot. Its throwing P0300 and occasionally a specific cylinder code for cylinder 7 or 1. I used a spark tester, and cylinder 1 and 7 seem to be getting spark normally, inspected the new spark plugs and confirmed they are ok, checked fuel pressure, and according to the obd2 data the vacuum level is normal.
I am going to do a compression test next but I think that maybe the valves are stuck or sticky, because i'm not sure what else it could be.
One other peculiarity is that when I turn the key to the run position the fuel pump never shuts off, I have replaced the relay and it still does this. Not sure if it is related however. I am also getting a weird reading from the sensor TID: $07 CID:$0d in torque pro which gives a current voltage of 56,320 and a max of 197.