C15 help!!

Hi everyone!! I've already tried asking in the owner operator section but no luck..... so Im gonna try it here to see if anyone experience this before..... There is something wrong with my C15 CAT motor but I dont know what is it.. Pls help me figure it out...


Yesterday it happened a couple of times when i was waiting for my load, I was just sitting in my truck idling and the truck suddenly wants to shuts off (not completely shut off) and turned back on by itself right away less than a second... and it happened while Im driving too, same thing it wants to shuts off and it comes back on by itself... other than that the truck runs perfect, it doesn't shake and no it doesn't smoke... I took it to my mechanic and they plug in the OBC to check for codes but no codes were found... have anyone experience this before?? pls give advice...

I've changed the Throttle Position sensor.... need to calibrate it though..
change all the cat filters and oil, check the wires going to the battery but no luck same thing... what else could it be and what sensor or wire can cause the truck to do that?

 

good point PeteTech.. in the moment it does it only the engine light and a oil pressure light come on and then goes off after the engine turns back on...

At the moment it happens is like suddenly there is a loud beep and RPM goes really low, both check engine and oil pressure light comes on like its about to shut off and then jump back up to normal... once in a while the RPM will go so low that the motor shuts off completely

the warning lights doesn't cycle like when I turn my keys on when the problem happens, because when I turn my key on all the lights come on, not just two..
thats why I dont thing is the ignition switch fault...
what can it be......... pls help or give advice what to look for! I've replaced the TPS already, now I just need to calibrate it... but I dont think the TPS is causing this problem or maybe Im wrong

Thanks

 

Petetech
2001 Pete 379 C15 CAT 18sp electronic engine.
I replaced the filters trying to fix the problem,
At the moment it happens is like suddenly there is a loud beep and RPM goes really low, there is NO reaction when I hit the gas pedal until it turns back on. It happens for like one or two seconds.

550hpw900l
I've tried turning off the key and turn it back on really quick, it feels kind of the same like the problem, but when I do that all the lights in the dash comes on not just two. thats why I didn't look into the ignition switch yet.

Maxeffort
The engine light comes on because the truck is about to turn off on me, engine light goes away right after the engine turns back on..
"Might be a speed timing sensor. There are two, a primary and secondary. if one cuts out it will run on the other, but the engine will will seem to lose it for a
second."
yes, the engine looses it for a second...
maxeffort do you know where are those two speed timing sensor located so I can check them out..

Thanks for all the replies!

 

PeteTech

Last six 538883
Engine serial 6NZ20129

 

I'll be heading over to St. Louis, MO tomorrow to transport some goods and I will be back on Tuesday night, so I won't be able to reply you guys until Tuesday June 17.
Thanks again for all the help and replies!! talk to you guys next week