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I have a 2002 kenworth with a cat 6nz C15. The concern is…

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I have a 2002 kenworth...
I have a 2002 kenworth with a cat 6nz C15. The concern is low power when pulling a hill or getting up to speed. Fuel pressure is 85 psi. Pressurized intake-no boost leaks. I think it might have few weak injectors. Only other thing I found was outside air temp is reading 32 degrees when it is about 60 outside. Will this sensor cause a derate?
Submitted: 1 year ago.Category: Medium and Heavy Trucks
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Answered in 5 minutes by:
5/3/2021
Technician: Nich1019, Cummins/Caterpillar Technician replied 1 year ago
Nich1019
Nich1019, Cummins/Caterpillar Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3,298
Experience: Expert
Verified

Hello and welcome to JustAnswer! I'm Nick and I'll be helping you out today.

No, the engine ECM does not get any readings for the outside air temperature sensor.

Have you thoroughly inspected the turbocharger? If you push throttle to 100% quickly while parked do you get a puff of black smoke? Have you monitored fuel pressure while under a load?

Also verify that your barometric pressure sensor reading is accurate.

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Customer reply replied 1 year ago
barometric is reading 14.7 key on engine off. The turbo has been replaced along with intercooler and boost sensor. This was all done at another shop. The truck has almost 900,000 miles on it and they believe it is Virgin. The truck starts good no smoke. The fuel pressure is 80-85 psi at idle and about 90 at 1500 rpm. I just changed the fuel pressure regulator and it increased the psi a few poundsI was also thinking maybe the mufflers are plugged? Is there a good way to check exhaust back pressure
Technician: Nich1019, Cummins/Caterpillar Technician replied 1 year ago

If the mufflers are just open mufflers I doubt that they are plugged. They put catalysts on the next generation of engines, I've seen those get plugged once or twice. I would check that boost pressure sensor part number, I've seen oil pressure sensors installed there and it causes low boost. Now when you're idling parked and you slam the throttle to 100% right away you should get a puff of black smoke. Try this, and also have the compression brakes come on. See how high your boost pressure goes. It should hit probably 5 to 6 lbs.

To test for a plugged exhaust you'd have to install a pressure transducer where the pyrometer sensor is and measure the pressure.

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Customer reply replied 1 year ago
I just tried slamming the throttle. They is a very faint puff of smoke very hard to notice. With the jakes on high it only builds about 2psi of boost with a 100% throttle sweep
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