Power loss

[Trainedpro]

Have 96 6.5 Suburban, after approximately 1 hour of driving I have a huge power loss. Engine still Makes RPM's my truck doesn't increase it's speed.
Any thoughts.


Already installed remote PMD + New PMD
Boost gauge (makes plenty of boost)
Nick

 

[Gunner0812]

Have 96 6.5 Suburban, after approximately 1 hour of driving I have a huge power loss. Engine still Makes RPM's my truck doesn't increase it's speed.
Any thoughts.


Already installed remote PMD + New PMD
Boost gauge (makes plenty of boost)
Nick

Might be the turbo but it should smoke lot if it is. Can you get yours hands on a OBD 2 scanner?

 

[Trainedpro]

I've gotten a few P0236 codes but my turbo is building 12-14psi of boost.
6 months ago I had no boost due to my vacuum pump and I still had more power than I do now.
Big issue is the temp spikes 10 degrees just driving and overheats when towing.
I was thinking I was loosing a cylinder or two but not sure.

 

[JMJNet]

I've gotten a few P0236 codes but my turbo is building 12-14psi of boost.
6 months ago I had no boost due to my vacuum pump and I still had more power than I do now.
Big issue is the temp spikes 10 degrees just driving and overheats when towing.
I was thinking I was loosing a cylinder or two but not sure.

Please DO the diagnostic checklist!!! and create your own thread for that.

 

[ak diesel driver]

I've gotten a few P0236 codes but my turbo is building 12-14psi of boost.
6 months ago I had no boost due to my vacuum pump and I still had more power than I do now.
Big issue is the temp spikes 10 degrees just driving and overheats when towing.
I was thinking I was loosing a cylinder or two but not sure.

If I recall correctly the pcm will only tolerate 12lb sustained boost then I think it defuels to lower boost. Anyone else know more about that.

 

[Turbine Doc]

TP we can help you better if you have your own thread, rather than have you post in middle of an existing thread.

 

[Turbine Doc]

If I recall correctly the pcm will only tolerate 12lb sustained boost then I think it defuels to lower boost. Anyone else know more about that.

Correct AKDD

If coding from a boost code 0236, it can defuel if corrective action by PCM (lower boost) does not clear the code, high IAT will also cause a defuel. But what we don't know at this point, are you setting 236 before or after your issue?

Possibly you a bad (high) MAP(boost) sensor, that sets defuel for overboost. (need more info)

Do you have a scan tool that allows you to see what IAT you are seeing, and what boost is being seen at PCM. You said 10F higher temp, what is going higher, water temp ???

Fill out the diagnostic sheet as best you can we need more info before making a effective call

 

[buddy]

Is the tranny fluid full when hot? Defueling sounds like RPMs would go down, unless its also downshifting? What speeds are you talking about.

 

[Burning oil]

Is the tranny fluid full when hot? Defueling sounds like RPMs would go down, unless its also downshifting? What speeds are you talking about.

I was thinking trans also.