TweetyBird

My truck was suffering from power loss, Big Time. The smarty jr on economy smoked like crazy, so I put it back to stock. No power whatsoever and it threw a 0299 low boost code. I took it to the dealer, and they put on a new turbo under warranty, and a new turbo sensor. They checked the intercooler, and it was ok. It still lacks power, they said there was an exhaust restriction. They said they would not touch that part because it has an aftermarket exhaust (MBRP 5" Cat Back). So I do not think it is the cat back, it is only a few months old. It must be the converter? Today I put the smarty jr back on, in tow mode it smoked like crazy, on economy it also smoked a lot. Any suggestions?

OOPS

Leave the cat on, pull the muffler off, and see how it runs. Some of the baffles in the muffler could have broken loose and are causing a restriction. If it still runs the same, it is the cat.

D-Roc

What's a catalytic converter? I don't think I have one of those....

NickBeek

A guy I know with an '07 5.9 had similar issues, the dealer found the wastegate was bad. I'm not sure if the waste gate comes with a new turbo or they may have swapped your old one in. Worth asking the question of them. I don't see the cat getting clogged, but anything is possible.

TweetyBird

Yeah, it came with a new wastegate........

torquefan

Have seen and repaired several plugged cats on 12 valves, but never yet seen it on any 24 valve trucks. Simply monitoring the maximum boost pressure on a test drive before and after dropping the downpipe from the turbo will tell the story.

TweetyBird

It had good boost with the down pipe off, but low boost when the exhaust was hooked back up...

OOPS

Well now you know that there is a restriction in the exhaust system. do what I said and work on back.