Det Sensor Question

[Sled169]

Another 09 D8 with scuffed PTO side piston

The CEL on my 09 D8 came on the other day about a 1/4 miles from the trailer. I did not try to count it, it seems to just be flashing constantly. I can shut down and restart and it goes away until I try to get over about 6000 RPMs then it runs like crap and the light comes on again.

I found that the DET sensor was loose in the head and that the threads are striped out. I am going to try and drill it out and Heli Coil it back on so that it will stay tight. Will the DET sensor being loose cause it to go into limp, and throw a code like that?

 

[Butta]

For your own education, I'd pull the exhaust valves and take a peek at the pistons. 4 bolts and they both will be out, and you'll at least have some confidence in the integrity of the motor if it all looks good. I bet you'll see some suffing, though....

 

[Sled169]

Found a couple issues, the det sensor was loose, i was able to get it to tighen down, and with all this talk about scuffing, the gizmo and burn downs I decided I better take a look at my pistons and see just how things are looking.

PTO Side looks like it has scuffing, Mag side looks OK.

Next step I pulled the head and check the cylinders, they look good, PTO side has one small spot it that scuffed but I can't feel it will my finger nail it all feels smooth. So I think it is ok.

Guess I will put in a set of pistons and see what happens next.

 

[theshadowrider]

How much scuffing is normal or is scuffing normal? What did you decide to do? I checked mine and its has rub marks. Not sure I would call them scuffs but it its wearing through the coating. Not as bad as these pictures but similar. If you replaced you pistons, take a picture of them once they are out. I

 

[Sled169]

I pulled it down and sent the all the parts out to be looked at by someone who knows more about it than I do.

Although the scuffing does not look to bad when you first look in there, any sign of marks is an indication that you have had a problem at some point. If it were me I would tear it down all the way and check the cylinders below the exhaust port. Mine did not look like ther was anything wrong from the top, even after I had the head off it all looked ok, but when I pulled the cylinder off I found where the scuffing ofn the pistons happend at.

It is best to take care of it early, if you let it go any longer it could go from a $500 repair, (set of pistons and a hone job) to $1500 repair (set of pistons and a new cylinder) or worse if something goes through the cases.