I have been getting a funny turbo surge for a little while now and it has seemingly gotten worse lately. Here's what i know...

**Turbo surges pretty quickly...faster than auto enginuity can map the spikes and drops in boost pressure, which makes it hard to read all the sensors and see if any of the readings are spiking and dropping in the same pattern.

**If i modulate the actuator and close the veins it does not surge. If i modulate the actuator and open the veins it does not surge.

**EBP sensor is brand new and the SS tube cleaned, went out on a limb even though it has been flashed with the latest...

**2 new injectors, all 8 at 100% on the contribution test.

**Took the turbo off and scrubbed it about 6 months ago

**Cleaned the EGR valve last month...replaced my EGR valve with a buddies who has no surging...my truck still surges

Took it to a nearby diesel shop and he said he thought it might be a bad HPOP (which is only about 6 months old). However the oil pressure was steady with no spikes or drops, and with the truck not surging with the veins open or closed it's hard to imagine its an oil pressure problem...

I need some help

 

Maybe give the turbo a cleaning? To me it sounds like it's probably surging while the veins are trying to adjust. Just a guess from a rather inept individual though

 

there is a simular thread going right now.
disconnet the ebp and see if the issue goes away. if so suspect possible concern with vgt accuator and or connector.
disconnect the icp sensor and see if it goes away. if it does plug it back in and moniter ipr with eot at or greater the 185* at idle with a/c off ipr should be around 24%.
if its much higher suspect a leak in the high pressure system causing your concern.

 

I have seen turbo surges not repaired after a turbo recondition due to 3 things...first, the turbo wasn't cleaned properly, second, the unison ring is worn out on the hole for the actuator lever, third, the actuator rack mechanism inside the turbo is worn.

The third one was hard to find, but after studying it, I found that with the turbo apart and inspecting the shaft, there was too much freeplay in the mechanism before the piston of the mechanism actuated the shaft/lever.

Like cheezit said though, an EBP or ICP issue can also cause surging. Really depends on how the problem sounds and feels to put my finger on it.

 

Slightly off topic: Is there a maximum boost pressure that the MAP will read?

 

sure is. its the max you turbo will put out.

 

Thanks guys, i will plug up in the morning and see what i can uncover. But since i've got a couple of you guys' attention...especially since some of you(techs) see these things often. Where are some common places for a leak in the high pressure system? I had it replaced about 6 months ago so there is a possibility something was not put back together correctly...

 

by high pressure system do you mean boost or oil?
most boost leaks are at the blue boots
most oil leaks are dummy plugs and stc fittings.

 

EBP sensor unplug did it...guess i will try for another cleaning...especially since i found the in depth cleaning guide after i cleaned mine. If not i guess the actuator is the next suspect. I thought i read somewhere that the latest ford flash overlooked the EBP sensor...

 

you issue is the vgt silenoid. IMO anyway.