XChris1632X
September 3rd, 2013, 01:59 PM
I have an 02 Tahoe 5.3 that my wife drives. I bought it with 240k on the clock at a good deal. It now has 265k and is still in good shape but it has an intermittent miss that is getting worse. I am trying to get more familiar with efi live and hoping I can use it to help me diagnose the issue. I know intake gaskets are an issue on these engines and I have even had a tech write that one is leaking after my wife took it in for an oil change when I was out of town. I however, have not been able to confirm the leak with carb spray. I notice no change in idle and see no visual signs of leaking. I am getting misfire codes from cylinder 2 as well as some evap codes this latest time around (it has been missing for two years slightly).
I don't want to just start throwing parts at this or wasting a lot of time changing stuff that shouldn't be. I was hoping there were some ways I could use this to help me look at some things such as spark, fuel injectors, and 02 sensors. It will sometimes idle rough cold and other times it wont. Some times it will do it more when it heats up. It is starting to effect transmission shifting. It acts as if it wants to take it out of lock up at times. I have never got the flashing SES light but the standard CEL comes on for a couple weeks and then goes off. If I run the vehicle hard with a lot of throttle it runs good but possibly might be leaving power on the table somewhere. Part throttle is not great and seems like it is really down on power when trying to accelerate 40-60% throttle. I don't notice it when cruising steady but with slight accelerations from a cruising speed like 45 mph for example, it will stumble or buck a few times very quickly and then come back.
Hoping someone can point me in the right direction.
I don't want to just start throwing parts at this or wasting a lot of time changing stuff that shouldn't be. I was hoping there were some ways I could use this to help me look at some things such as spark, fuel injectors, and 02 sensors. It will sometimes idle rough cold and other times it wont. Some times it will do it more when it heats up. It is starting to effect transmission shifting. It acts as if it wants to take it out of lock up at times. I have never got the flashing SES light but the standard CEL comes on for a couple weeks and then goes off. If I run the vehicle hard with a lot of throttle it runs good but possibly might be leaving power on the table somewhere. Part throttle is not great and seems like it is really down on power when trying to accelerate 40-60% throttle. I don't notice it when cruising steady but with slight accelerations from a cruising speed like 45 mph for example, it will stumble or buck a few times very quickly and then come back.
Hoping someone can point me in the right direction.