so the Check engin light comes on randomly now and when i scan it this is what comes up... any ideas to what this is? the light does not come on all the time

 

Boost circuit problem. Disagreement between demanded boost and actual boost.

Likely causes (in order):

1. Wastegate solenoid
2. Vacuum pump
3. Vacuum pot on turbo
4. Vacuum lines leaking
5. Boost leak
6. 2 bar map sensor failure
7. Turbo failure

I'd check all my connections for corrosion and broken/cut wires before starting to throw parts at it.

Then move on to checking the vacuum pump output.

Then check the wastegate solenoid with the key on to make sure it allows vacuum through with power on.

Then on to test the vacuum pot on the turbo and the vacuum lines.

A mityvac hand vacuum pump and a vac gauge are your best friends when checking out the vacuum system....

 

replace the sensor, get a turbo master and throw the vaccum pump in the trash.

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when you clear it hw fast does it come back?

 

With all due respect, 99% of the time that code is caused by the wastegate solenoid failing, not the 2 bar map sensor.

A TM is a good idea, but it's going to cost you some MPG.

For MPG, the vacuum system is King.

For towing, simplicity, reliability and performance, the TM is King (unless you can tune your own boost tables that is..... )

I suggest the OP choose which way he wants to go based on his own personal needs....

 

yea i understand that, i would clear the code and see how fast it comes back
turbomaster=$110
vaccum crap= $200+
"the best reason to have the vaccum system in a 6.5 is to throw it away"- Bill Heath

 

thanks guys ill looks at it and see how it all looks it, the light only came one once when i was flooring it up a steep hill.. and has not come back on since and i go up the hill every day..

side note... i have been looking at the turbomaster and.. is it realy that much of a diff in just daily driving?

 

From a guy who has one on his 98 K2500 with a factory GM8 Turbo for "just" daily driving:

No.

Now if you're going to tow or turn up the fuel delivery (more HP);

Yes, totally worth it for EGT control.


It is a simpler system and from a maintenance and reliability point; worth it.

You spend 100 bucks for a turbo master and never have to replace it. You can spend more than that on a vacuum pump and it will probably last another 5-10 years. Then there a 55 dollar vacuum solenoid that lasts on average 5-10 years, and a wastage vacuum pot that can go (100-150 bucks, maybe more), or you could loose the vacuum lines and have to replace them.

 

my truck didnt have any ***** until i put that TM on. you feel it instantly like your driving a new truck.

 

Then your stock vacuum system wasn't up to snuff when you swapped.

Made virtually no diff on my truck in daily driving other than egt control.

All the turbo master does is keep the psi up where the vacuum system drops it to 0 as soon as it can.

What you may have felt is the bit of extra fuel the PCM was adding because the added boost forced it into a different fuel scheduling in the look up tables....That's all a TM does, keep the boost up in all situations to enable more fuel.

Air isn't power; fuel is.

More air means, well, just more air.

Now, once I reflashed my PCM to take advantage of the added air it started to come alive....not a monster, but noticeable.

I could have done the same thing by reworking the vacuum tables in the PCM. I was pinched for time when mine went on so I didn't have the luxury of playing with tables for a month or two to get it where I wanted it.

But hey, if you slap on a TM and it feels more powerful to you I guess its worth the cash....

 

did you take it to the dealer to have the PCM reflashed after the TM?