Limp Home Mode

[coolio4433]

Good to know. Thanks Bill.

I won't worry too much about the code then, and when my custom tune is ready it sounds like I shouldn't have this problem anyways.

[88Racing]

Originally Posted by Power Hungry

I had addressed this in an earlier thread, but can't seem to find it at the moment.

Anyway, from what we've seen this phenomenon seems to happen immediately after programming a truck and driving it for the first time, especially under hard acceleration. The PCM triggers the P061B DTC, pops the "wrench" on the dash, and the engine goes limp. After cycling the key, the problem usually doesn't reoccur until the next programming session.

As near as I can tell, the PCM is detecting a disparity in calculated torque versus a preset estimated torque table witch triggers the P061B DTC. Why this usually only happens once is still a bit of a mystery and there are minor corrections we can make to eliminate this issue entirely.

It should be noted that we only ever see this problem on vehicles with CAIs and usually only when running canned tunes, although some earlier custom tunes may exhibit this issue as well.

As mentioned, any custom files with this issue can be modified to resolve this issue. Just let me or Corey know and we'll get it on the rebuild list.

Take care.

That's probably why we say not to hammer it and be nice when running L2 canned tune and a cai.

Lars

[MercedesTech]

Originally Posted by Power Hungry

I had addressed this in an earlier thread, but can't seem to find it at the moment.

Anyway, from what we've seen this phenomenon seems to happen immediately after programming a truck and driving it for the first time, especially under hard acceleration. The PCM triggers the P061B DTC, pops the "wrench" on the dash, and the engine goes limp. After cycling the key, the problem usually doesn't reoccur until the next programming session.

As near as I can tell, the PCM is detecting a disparity in calculated torque versus a preset estimated torque table witch triggers the P061B DTC. Why this usually only happens once is still a bit of a mystery and there are minor corrections we can make to eliminate this issue entirely.

It should be noted that we only ever see this problem on vehicles with CAIs and usually only when running canned tunes, although some earlier custom tunes may exhibit this issue as well.

As mentioned, any custom files with this issue can be modified to resolve this issue. Just let me or Corey know and we'll get it on the rebuild list.

Take care.

Bill, How ya been ? Its been a long time since we last talked. Hope everything is going well with you and yours.


I was probably one of the first people to report this problem to you. It happened with my canned tuned, and then continue to happen with my custom tunes. I do NOT have CAI. But, I have learned to live with it, as it is really no big deal. When you first load a custom tune, realize it will go into limp home mode. I always set my custom tunes in large open parking lots. Once it is loaded, I drive off. Within a few minutes the wrench is thrown. I put it in park, go into diagnostics on the Gryphon. I clear any and all trouble codes. Turn off truck. Restart truck and you will be good to go. It has taken me one or two times to get it, but that is why I advise any tune change to happen in a large open lot. That way you have plenty of room to test drive it after each loading session. Just my 2 cents.

If there is a way to fix this, I would be interested in it.

[Power Hungry]

MT,

There is a fix for your situation. I'll get you a new rebuild the first of the week and that should take care of your issues.

[MercedesTech]

Bill, I went out of town and business had just been booming, and crazy, and just too much going on. Seems like I got some things back under control, and everything is back to the normal smooth everyday stuff.

Anyway, was there any update ? What do I need to do on my end ?? Thanks a lot.

[Power Hungry]

James,

Update loaded. Make sure you are using the latest version of Pegasus (v2.01.0594) before you update.

Let me know if there are any further issues.

Take care.