Cummins Fault- PITA

[HMCSW]

So we get the fault code SPN 103 ( slow turbo) a lot. We NEVER idle at long time because that is one of the causes. Never the less it comes a goes from time to time. Anybody else get this? We took the coach to Frieghtliner for the 6,000 service and the light went out just as we pulled into their shop. It came back on on our way home.

[EA37TS]

Which Cummins engine and have you signed up for DTNA and checked their resources?

[HMCSW]

Originally Posted by ea37ts

which cummins engine and have you signed up for dtna and checked their resources?

6.7: 360hp

[HMCSW]

Originally Posted by EA37TS

Which Cummins engine and have you signed up for DTNA and checked their resources?

6.7 360HP. Not DTNA but have through Frieghtliner. Have taken it in and code cleared once. The code came up before I left the dealer parking lot when we purchased. That is when they said to make sure never to idle below 1100 RPM as it will through the code. Nothing they can do if the fault clears before I get there. Taking it in this week but just checking to see if other have the same issue. It is related to the DEF and needing the turbo to spin above a minimum.

[TurnerFam]

it sounds to me like a simply 'ground' issue, or similar problem that can only happen at certain times - our 6.7l ISB 300hp with turbo never had this issue in over 110,000 miles, and with many times idling for long periods for various reasons. I would suspect the 'sensor' might be suspect, possibly not always having the 'ground' it expects.

[EA37TS]

Originally Posted by HMCSW

6.7 360HP. Not DTNA but have through Frieghtliner. Have taken it in and code cleared once. The code came up before I left the dealer parking lot when we purchased. That is when they said to make sure never to idle below 1100 RPM as it will through the code. Nothing they can do if the fault clears before I get there. Taking it in this week but just checking to see if other have the same issue. It is related to the DEF and needing the turbo to spin above a minimum.

I have the 6.7 360hp and I idle at 800 and have never thrown a code. Find someone that knows what they are talking about. My rig has over 10k and I have never got a turbo code.

[HMCSW]

Originally Posted by EA37TS

Which Cummins engine and have you signed up for DTNA and checked their resources?

Spoke with Cummins: said basically ignore the fault as it will self clear after a couple trips. They can't really know why it trips unless the code is active when I role into a shop and the shops in Portland are two weeks out. They said since it has happened 6-8 times since March it is not likely anything to worry about. It can only be a couple things other than the idle: faulty sensor or turbo.

[powerboatr]

slow turbo seems ambiguous
could be the vane actuator is not getting enough oil pressure to change its position when throttle is demanded
the variable vanes can stick from soot of corrosion ..how many hrs are on the engine and did it sit long time in a humid salty area?

how does it behave on highway at speed

either way...dont settle until its fixed correctly
the DONT let it idle statement is hoooooey

the engine will ramp up rpms if idling and temps get out of whack


be the squeaky wheel and have it corrected.

[HMCSW]

Originally Posted by powerboatr

slow turbo seems ambiguous
could be the vane actuator is not getting enough oil pressure to change its position when throttle is demanded
the variable vanes can stick from soot of corrosion ..how many hrs are on the engine and did it sit long time in a humid salty area?

how does it behave on highway at speed

either way...dont settle until its fixed correctly
the DONT let it idle statement is hoooooey

the engine will ramp up rpms if idling and temps get out of whack


be the squeaky wheel and have it corrected.

No salt water or anything like that. Most likely sensor or the ECM but since it is sporadic and it runs fine just need to have the fault code active at the time I pull into the shop. Your short bus a SOC?

[m1noel]

Have never seen that one, 20K miles now.

[HMCSW]

All fixed... Frieghtliner took care of it: Called the shop (Oasis) Thursday morning, dropped the coach off Thursday afternoon. Picked it up Friday morning. Faulty Speed Sensor replaced.

[powerboatr]

Originally Posted by HMCSW

All fixed... Frieghtliner took care of it: Called the shop (Oasis) Thursday morning, dropped the coach off Thursday afternoon. Picked it up Friday morning. Faulty Speed Sensor replaced.

EXCELLENT

[simidrm]

Not sure if this is still an active conversation but if your getting a slow turbo code I would suspect the turbo speed sensor or the turbo actuator, just a FYI but there is a tsb out on this problem that if your vehicle is in the recall Cummins will replace the sensor or actuator under warranty, there is also a tsb out for the scr system to be inspected or replaced if in the recall the scr system is what uses the def

[HMCSW]

Originally Posted by simidrm

Not sure if this is still an active conversation but if your getting a slow turbo code I would suspect the turbo speed sensor or the turbo actuator, just a FYI but there is a tsb out on this problem that if your vehicle is in the recall Cummins will replace the sensor or actuator under warranty, there is also a tsb out for the scr system to be inspected or replaced if in the recall the scr system is what uses the def

Thanks. Frieghtliner replaced the failed sensor and it has been fine since.