P0299 Turbo Boost Low

[Mark Rinker]

Driver called - was experiencing sluggish performance pulling hills with ~7K# sheet steel on gooseneck and K3500 dually. Said he was also seeing black smoke intermittantly, and had a SES light on...

Stopped and changed fuel filter, no improvement. Stopped at a GM dealer, pulled code, changed air filter. Initial test drive seemed better, continued to delivery point but the problem re-occurred intermittantly, and eventually the SES illuminated again.

Returned to the small town WI dealer, pulled the same code, and was informed that our 'turbo must be bad' and they'd have to tear into it to find out more.

"No *&^%'in way...its something simple" was my response to the driver. I was in Cali pulling a boat with the other truck. "Keep looking..." Pretty soon, a hissing sound led to a loose intercooler hose (bottom). It wasn't all the way off - but close enough to leak under acceleration in the hills.

Keep it simple. Often times, it is. :)

[Runaway_Dmax]

I hear ya. My VW wasn't performing right after I got it back from being repaired from a deer crash. No Lights or Codes but felt like it had no boost.

Got it in a warm shop to look it over and found an intercooler hose loose and a waste gate line not connected. Found out that the waste gate was dumping all the boost.

After that performace came back, yeah my VW is a diesel ;).

Sometimes it is simple! Good to hear Mark.

[More Power]

If a loose intercooler hose connection developed on its own with a properly tightened clamp assy, GM has a special sealant they recommend for helping to make a more permanent repair. One could assume that since they developed/recommend a specific sealant, that they have seen a few trucks with this problem. ;)

Back in the early days of the LB7, there were occasional owner reports of loose intercooler clamps. In most of these instances, the problem was incomplete tightening at the factory, and it was pretty easy to solve. :)

Jim

[Mark Rinker]

Do you have a part# for the sealant?