VIKING_MECHANIC
GMT 400 obsessed Swede.
Alright, so for the last few weeks, I've been having issues with my C1500 running. I can feel it shuddering, sometimes I can barely feel it and other times It feels like the entire truck is shaking.
So I look at the live data to see what is going on and this is what I see:
Okay, so one bank is running lean and other is running rich. Got it but not really helping me figure this out. I ended up replacing the MAF because I will sometime get a "no signal/low voltage" code. Usually cleaning the MAF and the codes go away. I figured it was time to replace it because I was thinking the ECU wasn't getting the correct information and was adjusting the air/fuel accordingly. I replace it about a week ago and I'm still having this issue.
I got home from work today, and checked the fuel pressure. From what I understand, the operating range for these Vortec engines is 62-66PSI. I turned the key on and the system primed to 60PSI. I started the engine and it fell to 50PSI and held there while running. I tried the test a few different times and every time it would prime to 60 and drop to 50 when running.
Do these pumps show any sign of early failure? I don't think this is because of a clogged filter/strainer or a restriction in the line as it happens rather randomly. I have noticed though it will seem to favor to do this in the morning when the air is cool and dense. And with the engine running both lean and rich at the same time, I'm at a loss on that.
What's you guys' take on this?
So I look at the live data to see what is going on and this is what I see:
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Okay, so one bank is running lean and other is running rich. Got it but not really helping me figure this out. I ended up replacing the MAF because I will sometime get a "no signal/low voltage" code. Usually cleaning the MAF and the codes go away. I figured it was time to replace it because I was thinking the ECU wasn't getting the correct information and was adjusting the air/fuel accordingly. I replace it about a week ago and I'm still having this issue.
I got home from work today, and checked the fuel pressure. From what I understand, the operating range for these Vortec engines is 62-66PSI. I turned the key on and the system primed to 60PSI. I started the engine and it fell to 50PSI and held there while running. I tried the test a few different times and every time it would prime to 60 and drop to 50 when running.
Do these pumps show any sign of early failure? I don't think this is because of a clogged filter/strainer or a restriction in the line as it happens rather randomly. I have noticed though it will seem to favor to do this in the morning when the air is cool and dense. And with the engine running both lean and rich at the same time, I'm at a loss on that.
What's you guys' take on this?