2005 6.6 duramax check engine

[ceaser_22000]

I have a 2005 GMC Duramax 6.6 while recently coming home through Virginia and West Virginia on North 77 my check engine light came on after about 3 or 4 good mountain passes. Stop for the evening the next morning the engine light came off pulling through the Flatlands no check engine light I don't have a obd reader any ideas I was pulling a 40 foot fifth wheel approximately 13000 pounds.

[_40Fan]

P0087 is going to be my guess.

[lynndiwagon]

The 2005 LLY was prone to overheating and there are some fixes for it. I replaced the LLY turbo inlet with the LBZ one to let in more air. I also deleted the EGR and rerouted the PVC. All of these made a difference. As far as the code goes, I also use the Torque APP on my android phone with an inexpensive blue tooth OBDII module. I've used this many times to read and clear faults on my LML.

[Charlie_D_]

This is just and FYI to the forum but:

Buddy had an issue with a CEL engine light on a gas car. He called OnStar and they told him what the fault was. I don't remember what the code was but he scheduled an appointment with the dealer and when he got there they told him that although OnStar gave him the CEL message they would have to check it again at an extra cost before they would make any repairs. Their check agreed with OnStar.

I have no other info. from him and I don't know if this is a standard sequence by all dealers or just this one.

[greatwhitenort1]

ksss wrote:
OnStar will tell you what your code is as well if you have it. You want to make sure you check it soon as it will cycle out of the computer and it will be lost.

Even if the CEL does go out with key cycles, it is stored in the ECM until it is read & erased with a reader.

[ksss]

OnStar will tell you what your code is as well if you have it. You want to make sure you check it soon as it will cycle out of the computer and it will be lost.

[larry_barnhart]

45Ricochet wrote:

LIKE2BUILD wrote:
The 2005 Duramax had some issues with overheating due to air restrictions in the intake design. It's possible that under your towing load that air restriction came into play and the engine was running too hot.

X2
Common problem with some of them. I have forgotten the name but a company in Utah made a Induction Overhaul Kit, nice aftermarket item to fix it.
Maybe Larry Barnhart will chime in soon as I believe he has one.

I do have the air system but mine was from Arizona by killer bee. I have never had an overheating issue. I also have the scanguage11 that shows the correct water temp. I do have one issue for the last 3 trips south when towing at higher elevation going up mountains. The intake air will spike and the fan will come on at a low speed but full blast at times. engine temp will be 197 so now I wonder if an air sensor or etc is making the intake air rise in temp. this shows on the scan guage. Not really an issue but is a new problem maybe. I might look into it this summer. Never had a cel light come on to really give you any help. My truck has been maintained to extreme overkill.

chevman

[N-Trouble]

ceaser 22000 wrote:
Engine temp and transmission temp were fine. I was inquiring if any one else has had this issue and what was done for future mountain driving. Not really looking for exact codes. I will check with parts store to get codes though.

What issue? Without a code we dont know what your issue was. There are nearly a hundred different codes these trucks can throw. So your asking advice on how to fix an issue that honestly nobody knows what it is. Just speculating... Without a code everyone is shooting in the dark here.

GET A CODE READER...

[Ruralgas]

ceaser 2000:
Get yourself a Scanguage 2 (or the latest version). Plugs into the OBDI port and you can use it to read codes and then clear them. Also you can monitor up to 4 different parameters at a time; like coolant temp, trans temp, air inlet temp, and many, many more.
The factory engine coolant temp gauge is very famous for reading low as the actual temperature increases into that 210 degree plus range.
This unit is very small and the other thing is you can move to a different vehicle if your not using your truck.
I use mine in my 2005 Duramax and my 2012 Mazda. Works like charm.
Just Google Scanguage and have a look. Well worth the money.
These vehicles need a code reader or as others have said, your just chasing your rear end in circles.
Good luck.

[ceaser_22000]

Engine temp and transmission temp were fine. I was inquiring if any one else has had this issue and what was done for future mountain driving. Not really looking for exact codes. I will check with parts store to get codes though.

[ktmrfs]

and you expect us to know what the code for the light was???

Seriously, the duramax, like virtually every vehicle, may set a CEL, but if the fault goes away after a certain amount of time and drive cycles, the light may go off depending on what the code was and how it effects emissions. So, in all likelyhood that is what happened. NOW, get either a GOOD OBDII reader or a shop that can read SET AND Pending, and codes that cleared themselves. that will tell you what the code was.

If the engine was running to hot, long before it sets a CEL, it will go into LIMP mode and reduce power. I have an 04.5, same as the 05, it takes alot to actually get them to truely overheat, yes the temp will go up, but overheating takes a lot of load.

[45Ricochet]

LIKE2BUILD wrote:
The 2005 Duramax had some issues with overheating due to air restrictions in the intake design. It's possible that under your towing load that air restriction came into play and the engine was running too hot.

X2
Common problem with some of them. I have forgotten the name but a company in Utah made a Induction Overhaul Kit, nice aftermarket item to fix it.
Maybe Larry Barnhart will chime in soon as I believe he has one.

[corvettekent]

The one thing that I learned about a Duramax is that to need to be able to read and reset engine codes.

[KD4UPL]

Get Autozone to read the code for free. Then we'll all know.

[donn0128]

And Your question is?
Without reading the stored codes there is no way to know. BTW if you have an android smart phone, download the app Torque, amd buy a bluetooth ODB dongle off of ebay. That will give you way more than just a basic code reader.