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I have an 03 C4500 with the 8.1. It's developed this issue where it will stall under a certain throttle load, not really dependant on RPM, but load. Needless to say, we can't duplicate it in the rack, only going down the road. :favorites68: Engine just cuts out, I still have full power. When this happens, I can cut the key off, turn it back to RUN and it picks right back up. Unfortunately, last time this happened, it loaded up and when I cut the ignition on, it blew the side of the muffler out :D I've been thinking fuel, as it acts like it can't supply enough fuel for the demand, but I'm second-guessing myself since the muffler blowout, because if the fuel cut out and made it shut off, how would the cylinders load up with fuel?

I put a gauge on it, it's showing right at 55 key on engine off, and around 50 at idle, and jumps up to as much as 65-70 when I gun it. I plan on taping gauge to windshield and going down the road, but haven't yet as it's dark and foggy here. Also, I know these things were prone to crank sensor failures, so that's on the table as well.

Any ideas?
 

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I have an 03 C4500 with the 8.1. It's developed this issue where it will stall under a certain throttle load, not really dependant on RPM, but load. Needless to say, we can't duplicate it in the rack, only going down the road. :favorites68: Engine just cuts out, I still have full power. When this happens, I can cut the key off, turn it back to RUN and it picks right back up. Unfortunately, last time this happened, it loaded up and when I cut the ignition on, it blew the side of the muffler out :D I've been thinking fuel, as it acts like it can't supply enough fuel for the demand, but I'm second-guessing myself since the muffler blowout, because if the fuel cut out and made it shut off, how would the cylinders load up with fuel?

I put a gauge on it, it's showing right at 55 key on engine off, and around 50 at idle, and jumps up to as much as 65-70 when I gun it. I plan on taping gauge to windshield and going down the road, but haven't yet as it's dark and foggy here. Also, I know these things were prone to crank sensor failures, so that's on the table as well.

Any ideas?
Mines c5500 8.1 gas 05 yr same pressure reading already replaced crankshaft sensor wires n plugs filters the maf i cleaned it looked good what was your solution
 
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