cm 870 hiccups

[akwman]

Hello All , I have an 07 kw t800 with the 565 870 . The air cleaners are external and mounted near the windows ,so you hear lots of air being sucked in . Oddly enough this thing it sounds like it hiccups occasionally .The air intake sound stops for a second . Has anyone experienced this before ? . It can happen at any time , usually in a turn or under load . Just odd . There is no power loss .I am not sure what it is .

[hhow55]

You likely have an egr cooler, that is plugged with soot.

[akwman]

(06-08-2019 )hhow55 Wrote:  You likely have an egr cooler, that is plugged with soot.

I am not so sure , I have encountered that situation on another truck with the egr. Significant loss of power, black smoke intense .

[Rtrucking]

I know on my cm870 in my Pete it used to bark through the air filter when shifting because the turbo let off pressure on it, wouldn't do it all the time just once in a while and when I put the bigger intake on it the barking stopped when shifting

[Rawze]

if the turbo is over-working itself because you have CAC or other air leakage (or exhaust restriction)related issues, it will "caugh/bark".

It is also bad for the turbo for it to do this.

what is your boost pressure(s) looking like under different driving conditions?

[akwman]

Thank you . I am not sure what the next step is . Probably a visit to someone who knows way more than me about this thing .

[trucklogger2]

One area you may want to check out is fuel and timing actuators. Check plugs for moisture and search on this site for checking tolerances and cleaning actuators.