Turbo Overboosting Issue SOLVED

[tabraha]

Wanted to post a thread just in case anyone else runs into this problem down the road. I had a severe overboosting problem (wrapped my gauges past 50psi) and what was done to correct it.

The primary source of the problem wat the VGT Actuator (5C3Z-6F089-BA) quit functioning leaving the vanes unable to move and a worn unison ring (3C3Z-6C885-A). Turbo runs like new with normal boost and power is now restored. Glad I had the engine studded with ARP's though. I would imagine the stock head bolts would have stretched with all the pressure the turbo was putting on things.

[cowboyf250]

****. thanks for the info. my truck does this time to time. but only alil past 40psi. before the repair did it take like 20-25 seconds for the turbo start to spool upon first start up???

[swilson143]

Mine was donig similar things. Climbing hills boost would jump to 37psi and would not change unless I got my foot out of it... and it did stretch my bolts. First they put in a new unision ring and turbo center section... and I was back just weeks later for the head gaskets (and studs).

[tabraha]

Originally Posted by cowboyf250

****. thanks for the info. my truck does this time to time. but only alil past 40psi. before the repair did it take like 20-25 seconds for the turbo start to spool upon first start up???

For me it was very inconsistent at first. Sometimes it would hook up and go other times it would just not get-up-and-go and throw the boost through the roof. Sometimes it acted like it didn't want to spool up and others it would just go nuts. Here lately it just pretty much quit adjusting the vanes at all and would go straight into super high boost with any good amount of fuel.

[tabraha]

Originally Posted by swilson143

Mine was donig similar things. Climbing hills boost would jump to 37psi and would not change unless I got my foot out of it... and it did stretch my bolts. First they put in a new unision ring and turbo center section... and I was back just weeks later for the head gaskets (and studs).

Yeah I've been reading your threads. Hope they get things squared away eventually.