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+--- Thread: X15 2450 low power (/showthread.php?tid=10485)
X15 2450 low power - migueljc - 01-25-2026
hello everyone. I own a Peterbilt 22 x15 CPL5770 serial 80356908 I’m experiencing lost power and high fuel consume 5 mpg no codes no mechanical issues I suspect bad ECM any suggestions or mechanics interested on work in
RE: X15 2450 low power - tree98 - 01-25-2026
Poor fuel mileage and loss of power is extremely broad. Can you give us more details? What is the max boost in a hard pull?
When is the last time you did an EGR tuneup?
Has it had any work done to it ? New injectors installed?
Is it stock or demandated? If it's demandated you need to copy the file out and send it to Rawze for review.
RE: X15 2450 low power - migueljc - 01-25-2026
max boost around 28 I tink it is low. no recently jobs or injectors i recently bought this truck.
RE: X15 2450 low power - tree98 - 01-25-2026
Did you buy it in this condition or has it declined since you bought it?
Is it demandated?
RE: X15 2450 low power - migueljc - 01-25-2026
it have been getting worse. it’s stock. I bought from a big fleet I’m the second owner. I have noted when it lost power Iost power I have to pull out after re star the engine it improves performance a little bit unless to run at 65 mph
RE: X15 2450 low power - tree98 - 01-25-2026
Do an EGR tuneup and see if it improves. The cans probably need baked too. How many miles are on it?
RE: X15 2450 low power - migueljc - 01-25-2026
Currently 450k miles on it.
The DPF filters have been cleaned by the dealer before I bought it. KW declares.
RE: X15 2450 low power - Rawze - 01-25-2026
(01-25-2026 )migueljc Wrote: Currently 450k miles on it.
The DPF filters have been cleaned by the dealer before I bought it. KW declares.
that does not mean much of anything. They only do that so it does not fault out during a test drive.
DO an EGR tune-up... replace all related sensors, etc. .... The steakers$its are not about to do any of that.
info: https://rawze.com/forums/showthread.php?tid=842&pid=7030#pid7030
RE: X15 2450 low power - migueljc - 01-25-2026
I’m going to do the egr tune up.
I have replaced the map and exhaust gas pressure sensor already