P2580 Turbo Speed Sensor Circuit Low

[dlmetzger]

Just got P2580 tonite. We're leaving tomorrow nite for a week with the horse trailer in tow. Does this code signal the end of our plans or can it wait? I pulled some data with a code reader.



Calc Load 28. 6%

ECT 188 F

MAP 47. 2 inHg

Eng RPM 1878

Veh Speed 34 mph

IAT 149 F

MAF 14. 967 F

TPS 33. 7%

Run Time 838 sec

Fuel Press 16038. 1 psi

Command EGR 30. 9%

EGR Error 0%

Fuel Level 78. 8%

Baro 29. 8 inHg

O2 B1 S1 -126. 210 mA

EQ Ratio 11 0. 066

O2 B1 S2 -126. 210 mA

EQ Ratio 1 0. 071

CAT Te 11 610. 8 F

CAT Te 12 646. 3 F

ECU 13. 937 V

Ambient 87 F



Any suggestions?



Thanks

 

[HBarlow]

I don't know the answer and won't even guess. I hope that is not an indication of a sooted turbo not able to spin up to full boost. Hopefully you'll hear from one of our resident Dodge-Cummins techs today.

 

[2Rowdy]

Little bump to the top for ya.

 

[kbarlow]

This is in the 2009 Service Manual. I'm guessing it should apply to the 2008



P2580-TURBOCHARGER SPEED SENSOR CIRCUIT LOW

Theory of Operation

The Turbocharger Speed Sensor is a variable reluctance speed sensor. It consists of a coil of wire and an iron core. The target on the turbocharger shaft is a ground flat surface in the center of the shaft. As the flat surface on the turbocharger shaft spins past the speed sensor, a signal is generated. The Engine Control Module (ECM) interprets this signal and converts it to a turbocharger speed reading. If this fault becomes active the ECM will light the MIL light immediately. During this time the ECM uses an estimated turbocharger speed. An engine power derate may be experienced. The ECM turns off the MIL when the diagnostic runs and passes in four consecutive drive cycles.

When Monitored:

When the key is on and the Engine Control Module (ECM) detects a valid turbocharger speed.

Set Condition:

The Engine Control Module (ECM) detects turbocharger speed detected is less than a calibration limit for a calibratable amount of time.





Possible Causes

ECM GROUNDS

(K540) TURBO SPEED SIGNAL CIRCUIT SHORTED TO OTHER CIRCUITS

(K540) TURBO SPEED SIGNAL CIRCUIT SHORTED TO GROUND

(K540) TURBO SPEED SIGNAL CIRCUIT OPEN

(A209) FUSED B+ CIRCUIT

TURBOCHARGER SPEED SENSOR

 

[dlmetzger]

Thanks kbarlow for the info on the code. I took it to the dealer this morn. Haven't heard back yet. I don't think they will solve the problem today. The write-up for the code makes me feel a little better about going on the trip if they (the dealer) doesn't find a problem.

 

[dlmetzger]

Things are not going well

The dealer said it was just a bad sensor and they'd have the part in a day or so. The trip was to take girls to 4-H regional horsemanship competition and couldn't wait. I decided to not to wait for the repair. I thought I'd try a dealer in SC if things got worse. Well things got worse. About 300 miles into the trip the "Electronic Throttle Control" light lit. The truck could barely got over the hills. We could not hear the turbo whistle climbing the hills, but it would still pull the trailer. Decided to press on (~150 miles) and then take the truck to dealer in Clemson area. About 50 miles from our destination the "Catalyst Full" message shows 80%, then 90%". Finally make it, drop the trailer and then limp to the dealer. The dealer is backed up and may not get to it for days. Truck is used to tow horse trailer (5K-9K) in our local area. It is also used for highway trips. Have not had any problems with truck before. Disappointed.

 

[sag2]

I'm not sure the speed sensor code would cause the problem your having now. But at this point your kind of stuck. Worst case you can unbolt the DPF and bolt it back up with one bolt to keep it from dragging and drive it home that way. As long as the controller does not assume the DPF is full and go into torque limit you should be OK. If you decide to do that ask the dealer to reset the regenerative filter timers so it thinks everything is clean again. Do you have a code reader that can also clear codes?

 

[dlmetzger]

SAG2,
Thanks for the rely. I didn't think the speed sensor would cause my current problems either. Thanks for tip on the DPF. Unfortunately, I think my truck 'de-rated' itself before I got the 'Catalyst Full' message.
Its at the dealer and they just got to it yesterday. They did a stationary regen and said they were awaiting a new speed sensor. The dealer tech seemed to know about the 6. 7L, but just replacing the turbo speed sensor doesn't sound like it should fix my underling problems.
Yes, I have a code reader that can clear codes.

 

[dlmetzger]

Truck is still not well

Picked up truck from dealer.



Dealer write up:

Customer states check engine light on.

C/S the vehicle has no power. Catalyst Full message.



Removed EGR and cleaned. Removed DPF and cleaned. (? I think they did stationary regen. )

Removed O2 sensor and cleaned. Cleaned cross over tube.



Parts:

1 ea. 68002434-AA sensor in 8037155

1 ea. 68005256-AA gasket th 14062002

1 ea. 6027034-AB valve non 14038024

1 ea. 68028729-AA cleaner E 1081080



The mechanic said the sensor he changed was the intake pressure sensor, not the turbo speed sensor and it is ready to go.



I drive 7 miles down the road and check engine light is on again. I check it with the code reader and its the same as the original problem, P2580 for the turbo speed sensor.



Dealer is closed. They are open on Saturday, but don't know if I want to take it to them again. Was planning on leaving Sunday.



I have 33k miles on truck and it had been good to me. Now it's not being so good and I can't seem to find a good dealer mechanic to fix it.

 

[HBarlow]

I am sorry to read your report above. I have not been in that situation but have experienced taking my previous '06 to a dealer with a driveability issue and having a dumb and untrained tech advise me to run injector cleaner in the fuel tank. I read on the TDR, purchased a FCA from a Cummins dealer, and had my mechanic buddy install it. That cured my problem. Injector cleaner my axx.

Sadly lots of dealerships employ techs who masquerade as diesel mechanics but really know very little about them beyond recognizing the components and being able to remove and replace them or remove and clean them in your case. Some of these guys can only read codes and perform the steps directed by the Dodge literature.

I'm sure you are very disappointed and frustrated right now as your vacation days tick away and your family vacation erodes away each day . . . with a shiny new truck in the driveway.

Sag2 posted advice in answer to a question I asked about two or three years ago that I consider very useful in a situation like yours. I asked how to know if a dealer tech is qualified to work on my truck engine and sag2 explained that there are four levels of training and testing to obtain Dodge certification on the Cummins diesel engine. He advised to ask a dealership if they have a Level IV trained and certified Cummins diesel tech. The dealer where I bought my truck (300 miles away) has one but I have not needed him with my '08 C&C.

In fairness, there are older experienced diesel techs at some dealerships that are real mechanics who can diagnose and repair and also understand modern engines and computerized testing and diagnosis. Some have not bothered to complete Dodge certification and don't need to but real mechanics like them are few and far between.

TDR member Mike Mullenax who works at a Dodge dealer in Athens, TX is one of the good ones. He is older and experienced and can diagnose and repair our trucks. I took my truck across Texas a year or two ago to have him run a software upgrade. If you can get in touch with Mike Mullenax he can give you good advice.

I wish you luck.

Afterthought:

Your initial CEL and code referred to a turbo issue. I wonder why the dealer parts changer didn't remove and clean the turbo? I am certainly not a mechanic and do not claim the ability to diagnose or repair these engines but I would suspect a turbo related issue.

 

[dlmetzger]

Harvey,

I was a little surprised that they didn't do something to the turbo considering the error code.



sag2,

You asked if I had a code reader that could erase messages. I do. I'm leaving tomorrow (Sunday) and just want to make it back to Florida. The DPF is clean (hopefully), should I just erase the P2580 code every 50 miles or so until I get home? I think I'll also break the DPF inlet connection so it doesn't get full.

 

[kbarlow]

Cousin Harvey,



Thats not entirely correct. Just last week I had the Diesel Tech at our local 5 star dealer change the rear diff fluid. On reading the bill I noticed a charge for limited slip additive. After asking the service writer to show me in the manual were it says to use the additive, he could not. He then phoned and found that I was right. He told me that they have been doing this since 2003 when American Axle was first used in our trucks.



Sorry for hijacking the thread.



Cheers Ken

 

[HBarlow]

Thanks, cousin. I guess some of them can't read well or correctly follow written instructions either. And that's often what a customer gets for his $100 US an hour for dealer service. Don't know what it is in Canada now but probably similar. It's a damned shame but it is often the truth. Some techs are lazy and don't care, some dealers are too cheap to help them financially attend the Dodge training that is available.

 

[sag2]

Harvey,

I was a little surprised that they didn't do something to the turbo considering the error code.



sag2,

You asked if I had a code reader that could erase messages. I do. I'm leaving tomorrow (Sunday) and just want to make it back to Florida. The DPF is clean (hopefully), should I just erase the P2580 code every 50 miles or so until I get home? I think I'll also break the DPF inlet connection so it doesn't get full.

Yes, if your lucky they actually repaired the problem. Clear the code if it appears and see how long it takes to return. Also stop by a Napa and pick up a can of CRC diesel fuel therapy. If you have an injector that is a little dirty it might clean it up. Good luck on the way home.

 

[dlmetzger]

Made it back home

Arrived home late Sunday nite. At the start of the trip, I had disconnected the DPF inlet and erased the error code (P2580) at every fuel stop.



Took the truck to the local dealer on Monday morning. They replaced the turbo speed sensor and the gasket at the DPF inlet (the gasket was sticking out when I re-tighten the flange). Drove it home today (10 miles) and no codes. Hope it is fixed. Only time will tell.

 

[dlmetzger]

My mistake

Well the truck has been code free for a couple of weeks now. I reread the above posts and realized I made a big mistake. kbarlow had posted detailed information about DTC P2580. At the time I quickly scanned it for what I wanted to hear: "If this fault becomes active the ECM will light the MIL light immediately. During this time the ECM uses an estimated turbocharger speed. " With this, I thought the engine would continue to function.
What I missed was this valuable piece of information:
"An engine power derate may be experienced. "
I had enough information to make a good decision, but rushed and only looked for what I wanted to see.
I could have delayed one day for the local dealer to replace the sensor, not had any problems on the trip and dealt with the wifes complaints about the delayed start.
Instead, I rushed and I had to deal with a disabled truck and my wifes complaints about a ruined vacation.

 

[HBarlow]

It's very easy to quickly read something with several details when you've got troubles and pressures to deal with and fail to absorb and understand all the details. Hindsight often provides complete clarity to a situation like this.

Three cheers for my Canadian "cousin" kbarlow for initially having the correct information. It's unfortunate that none of us paid sufficient attention to his detailed post.

We all learn from an experience like this but only fellow TDR member dlmetzger was really inconvenienced by it.