Boost going down

[pwknapp]

Alright what's the deal? Ran a load today and usual boost is 35-36 WOT with a medium load. Couldn't get it above 28 today. Is it just the fuel filter? Will be changing that in the AM. Any help would be appreciated, I'm leaving on a run to Augusta tomorrow and am somewhat concerned. (1310 mi round trip)



Thanks in advance.

 

[KYOUNG]

LOOSING BOOST

MY TRUCK STARTED TO LOSE BOOST ONCE , TURNED OUT THE RETURN LINE AT THE BANJO FITTING HAD GOTTEN WEAK. THE BANJO FITTING IS A BYPASS VALVE TO KEEP PRESSURE UP IN THE FUEL PUMP. REAL EASY TO CHANGE, ITS RIGHT ON THE TOP BACK SIDE OF PUMP

 

[The patriot]

Did you check all of your connections? Intercooler, line to wastegate?

Eric

 

[illflem]

Check all the regular places like the intake tube clamps and manifold bolts. Intercoolers have been known to spring leaks. Wastegate may not be closing all the way. A pin hole leak in the boost gauge tubing is all it takes for the gauge pressure to drop without changing engine performance.

 

[pwknapp]

Intercooler and lines all look good, wastegate line is plugged do to 16cm2. Raining pretty good here have to check the banjo bolt in the am.



Thanks and are there any other suggestions?

 

[Six_Man_Diesel]

I would say check the boots on the intercooler, I had one come loose once. Other than that, I don't know. Did it feel like you lost performance???? might be the guage line, I've had that problem also, but that was my fault.

 

[pwknapp]

Thanks everyone. Changed fuel filter , checked all boost hoses and fittings, and stretched return banjo spring a tad. Boost back up to about 32 on real wet roads . Got soaked but sure feel better about running up to Augusta and back to get a load.



Sure do appreciate all who jump in with their experience and fixes.