New to diesels. I have a 2006 Chevy Express cargo van with a stock 6.6 Duramax. It starts and runs perfectly, but if i drive it hard it gets up to 2k rpm and starts to cut back on the power. If i don't ease up on the throttle the engine light comes on and it goes into some reduced engine power for 100kms or so then goes off. On the highway if i keep the revs down i can get right up to 140kms no problem. It only has a 130k kms on it so i think the motors still good lol. I plan to buy a code reader to check what it comes up with. Does innova make a mode that works on diesel engines cause thats the only make i can find here?

When was the last time you changed fuel filters ?

X2 filter

Good a innova 3130 code reader(250.00) and fuel filter today. It only took 20 minutes to do and she seems good once again. Thanks for the direction for the fix . Also clean MAF sensor just in case. The error code was P0087 Fyi to anybody having same issues.

Did you change both filters ?