Engine/Transmission (1998.5 - 2002) intermittent loss of boost

[whogan]

I have a problem. An under load intermittent no/low boost but with a P1693 DTC showing. No engine trouble light. No air leaks found. Runs good with good power. Removed Edge EZ, same problem running stock. Problem occurs under load, towing. Boost goes away, egts go up and remain for about ten miles on fairly level terrain. Had to drive 40 mph in 4th gear to keep egts down then suddenly boost returned. Your help is appreciated.

Thanks

 

[SUrich]

Is it still the stock turbo? Do you hear any athor noises like your exh. brake is on?

 

[KCraft]

do you have dead pedal???

 

[whogan]

Thanks for the response. No, everything else appears to be ok. Turbo is stock with no apparent problems there.

 

[SUrich]

It almost sounds like the wastegate is sticking open after it starts to open. Unplug you boost press sensor that will trick the ecm not to go into limpmode then get a pair of pinch off plairs and pinch off the wastegate hose on the turbo then go drive it. This will eliminate theactuation of the wastegate and will tell you if the wastegate is sticking or not. If it is sticking I think the only rapair for that is to replace the turbo.

 

[whogan]

Thanks to everyone for the help.