I'm on a trip right now with my 5000 lbs trailer. Everything was working great then suddenly I notice a lot of black smoke going up hills. I listen to the motor and notice that the turbo wasn't making boost. It sometimes works (I can hear the turbo) but sometimes doesn't. On long hills I really have to get into the throttle to get the turbo to make any real boost. When the turbo isn't making boost I get huge black smoke.

What do you think is causing this? I still have to drive home and I want to get this fix before I head back.

Thanks

Dave

May be your wastegate silinoid is on it's way out. Check your vacuum lines and see if they are not broken/leaking anywhere. Lots of posts about wastegate noid, do a search, but possible causes are:
-wastegate 'noid.
-leaking vacuum lines
-vacuum pump going bad

If you are putting the engine under a heavy load, your vacuum might not be strong enough to keep the wastegate closed. May have been a cronic problem not noticed until the load you've just put on it.

If you have good vac and the 'noid's bad, put the vac line from the pump on the turbo and don't throttle too hard or it will make too much boost.

I'd put my money on that WG solnoid, yours is acting just like mine did when it went bad. Try a WD-40 shot till you get home

I'm on a trip right now with my 5000 lbs trailer. Everything was working great then suddenly I notice a lot of black smoke going up hills. I listen to the motor and notice that the turbo wasn't making boost. It sometimes works (I can hear the turbo) but sometimes doesn't. On long hills I really have to get into the throttle to get the turbo to make any real boost. When the turbo isn't making boost I get huge black smoke.

What do you think is causing this? I still have to drive home and I want to get this fix before I head back.

Thanks

Dave
Do you have gauges? Assuming not. Typically, you will see the boost start to drift in the early stages of WG solenoid failure prior to getting as bad as you describe. You can also attempt to remedt this with a shot of WD-40 in the vacuum line that attaches to the turbo. Sometimes this can free things up. The OE vacuum system is really not that bad, but having gauges to monitor it (among ither things) is a must.


Oh, and get some gauges!

I'm back from my trip and did get the truck fix at my friends AAMCO dealer. Everybody was right on with the solenoid. Even the GM dealer said they sell tons of these. Truck runs great again and now I get 15mpg towing vs 12mpg going there.

I feel bad for smoking everyone out going up those hills here in BC. If you where one of the few following me this weekend.. I'm sorry.

Thanks

Dave