Engine/Transmission (1998.5 - 2002) ETH fuel cut off & boost ?

[tarussell]

I need some info on what would cause a stock ETH to create more boost than usual and hit the fuel cut off point.



This has only occured when the engine has been at full throttle for a long time and the RPM's are at 3200 or just below the red line. I have pushed the engine this hard before and it would just go to 19 PSI and stay right at the 3200 mark , but recently when I am running that hard the boost gauge will go to 22 PSI and eventually hit the fuel cut off.

When this happens the truck feels very strong and will only reach 22 PSI when it is at full throttle for a long stretch of road - driving around town the boost will not get past 19 PSI like usual. After this happens the truck feels really strong in fith and sixth gears but will not go past 19 PSI .



Note : the motor is all stock and the pressure fitting is in the air horn . The truck was unloaded the few times that it has done this.

Any pointers or insight as to why the extra boost is happening would be appreciated..... TIA , Thomas

 

[rashwor]

Just guessing...

Could it be a sticky wastegate??? These trucks have the capability to build boost into the mid 30s stock. I think the only thing that keeps them from doing that is the wastegate opening at a certain psi.



Does it set any codes when it does this?

 

[tarussell]

Thanks for the reply !

I did check for codes today and found that two were set .

P 0500 = Vehicle speed sensor malfunction

P 1693 = Turbo charge control circuit malfunction



Does anyone have any idea what these two codes actually mean ? The tire size is stock and always has been .



Any help would be appreciated , TIA , Thomas

 

[Pit Bull]

My service manual states that a fault was detected by the DTC. I would take it to the dealer and have it checked out.

 

[tarussell]

After spending some time digging through the Service manual I see that there is a code of P1693(M) and the DTC * I assume that this means diagnostic trouble code ???? * brief discription says " a fault has been generated in the companion engine control module " Than there is another code P1693(M) that says it is a " Companion DTC was set in both the ECM and PCM " .



Now, up top it says that the codes with the (M) beside them indicates " Malfunction Indicator Lamp ( MIL ) illuminated during engine operation if this DTC was recorded" . I have no such light being illuminated on the control panel.



Anybody in the know got any suggestions ?????



If this is a fix that I can handle I would like to take care of it ; if not than I will go out of town for a knowledgeable dealer to get it looked at .



Thanks for any info .....

Pit - thanks for the pointer to the DTC's ... ...

Thomas