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Ask go-west.. Your Own Question
go-west.., Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 1232
Experience:  Technican with 20 years experience focused on engines and electrical.
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I have a 92 peterbilt with ddec 3 Detroit. My problem is

Customer Question

I have a 92 peterbilt with ddec 3 Detroit. My problem is that over 1500 rpm my stop and check engine lights come on and engine derates. If I don't let off the throttle it will eventually die also it does not matter if I'm driving or parked
Submitted: 11 months ago.
Category: Medium and Heavy Trucks
Expert:  go-west.. replied 11 months ago.

are you able to get the blink code ?

do you have a chk eng button on your dash ??

Customer: replied 11 months ago.
It has a lot of codes do to me unpluging sencors to see which ones make both lights come on
Expert:  go-west.. replied 11 months ago.

Oil pressure

coolant temp

and low coolant sensors are the top 3 offenders that can cause this issue

Customer: replied 11 months ago.
But why only above 1500 rpm... it doesn't matter if the truck is cold or at operating temperature...
Expert:  go-west.. replied 11 months ago.

Good question

Getting the fault codes is the key

Customer: replied 11 months ago.
14. 23. 36. 41. 43. 45. 58. 63. 64. 85
Expert:  go-west.. replied 11 months ago.

14 coolant temp sensor,volt high...that will do it

23 fuel temp volts high....that might

36 oil pressure volt high...that will

41 missing trs That is a timing sensor that reads off the cam..that might me then one

43 low coolant---it will

43 oil pressure low--will

58 doesnt come up

63 and 64 dont come up

85 engine over speed--no this code is note only

Customer: replied 11 months ago.
Ok I will try some of those sencors and get back with you
Expert:  go-west.. replied 11 months ago.