Wastegate? boost hesitation.

[chelo]

I've noticed my sy start to hesitate a little more when in gear. For example I am entering the highways in drive (3rd) and i start to accelerate and notice my boost gauge climbs to zero and wont pass 4-5 lbs. Until i let off the gas and accelerate once again it spools up to 15lbs withouth a problem. I am currently running a manual boost controller set to 15lbs. Still using a stock turbo, stock t.c. Can it be my catalytic convertor? Wastegate? It doesn't happen all the time, but it's becoming more frequent.

 

[SeattleSy#1255]

stock WG sucks wang...i know mine was sticky and would act differently all the time. Thats the first place I'd check.

 

[chelo]

After loosing boost little by little, it finally doesn't make any more boost. Checked the wastegate rod and it was very close to where it should be. Never had problems before. Decided to check for a leaking hose and nothing. Hoses are new. Decided to go for a quick spin and it still made no boost so i decided to floor it and it made 2 to 3 lbs max and all i could hear after that was this screeching whining sound coming from the turbo and alot air being vented off from the wastegate after i let off the gas. Anyone with a similiar experience? I checked for play and it felt normal before the test drive. Seems that the turbo went south? Time to upgrade.

 

[Divergent Lightning]

If you still have a stock chip on your truck, I think I recall some sort of safety feature that doesn't let you go to full boost until you floor it a second time. This sounds like what you are experiencing.

 

[SY2932]

If you still have a stock chip on your truck, I think I recall some sort of safety feature that doesn't let you go to full boost until you floor it a second time. This sounds like what you are experiencing.

Correct, you cannot achieve full boost after you start the truck. Running an Ultimate chip eliminates this problem. From http://www.sportmachines.com/maintenance/beginner.php:
Special Features in the STG 3 bar chips:
Limit boost during first acceleration disabled,
Turns on intercooler pump when engine coolant reaches 60ºF thus eliminating the need and disadvantages of hard wiring the intercooler pump to run continuously.
RPM limit raised to 5400RPM,
Overboost fuel cut retained for safety reasons (2-3psi above boost level for that program),
EGR disabled in T3 (aggressive timing) programs, so as to not heat up intake (cruising to/from staging lanes),
Max knock retard raised (the stock amount of retard is limited to 12.66º, we raise this max to 18º).

 

[chelo]

I actually already have the ultimate chip. 50lb injectors and 3 bar map sensor. My truck seems to like the f1 t3 setting. I double checked and it was the turbo that was going bad. Truck was running excellent and spool up was amazing before this. Now it's time to shop for a real good turbo. I was still runing the stock one. I just have to wait after christmas to purchase one.