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I have a Cat 3126 8yl that is very slow to make boost. It's…

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I have a Cat 3126...
I have a Cat 3126 8yl that is very slow to make boost. It's in motorhome and normally it will make full boost (28psi) before the trans shifts into second gear. The exhaust temps are high when at part throttle (the sensor is after the exhaust brake and was reading 1150deg. F). I have replaced the fuel filters, oil and filter. I checked the wastegate and exhaust brake and they are fine. The intake system is pulling about 10". Any ideas?
Submitted: 3 years ago.Category: Medium and Heavy Trucks
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Answered in 2 minutes by:
6/19/2015
Technician: Cat Man, Cat Engine Expert replied 3 years ago
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 9,451
Experience: I am ASE Master Truck Certified.
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Hi. Thanks for asking your question! I will try and help you out.
Does the yellow check engine light come on when this happens?
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