04.5 hesitation REFLASH

[AFacey]

This post was taken from http://www.dieseltruckresource.com/dev/showthread.php?s=&threadid=38829&perpage=15&pagenumber=4





The hesitation will be fixed by the re-flash. It has to do with the ECM being temporarily "confused" by the missing tooth in the tone wheel. When it happens, the pilot injection is partially lost and sometimes if you get it just right the pilot injection is not given at all and that cylinder misfires. Its a very small "area" of the torque curve, so it shouldn't happen at WOT or light throttle.

 

[klenger]

I haven't noticed it, but then I tend to be pretty light on the go pedel, unless I'm towing, then I'm a lead foot.

 

[AFacey]

Klenger- From my experience, It has to be real cold outside - 30 degrees or below. You probably wouldn't notice it in sunny AZ. It has been mid 50's here in CO the last week or so and the problem is not evident.

 

[Gary - K7GLD]

sure seems odd that a "missing tone wheel tooth" would in any way be affected by temperature - unless it's like some body parts, and sorta shrivels up when exposed to the cold...

 

[klenger]

My grid heaters don't even come on in the morning any more with truck in the garage.

 

[RLighthall]

Originally posted by AFacey From my experience, It has to be real cold outside - 30 degrees or below... [/B]

AFacey,

When I posted the comment about the hesitation earlier in the week you asked me about the outide temp. Well, today it got to 58 degress where I work, and at home 60 someodd miles north it was 48. I tried accelerating under light load, heavy load, running higher RPM's w/OD locked out on the backroads - all the conditions that in colder temps temps made it go bonkers. This morning with the temps in the mid 30's it misbehaved as per normal, but later with the mild temps there wasn't even a hint of the problem. Hope the reflash comes out in time to test it while it's still cold...

 

[AFacey]

Rlighthall --- I hear ya!

 

[RobertBolinger]

It was above 60 on the way home today, and no hesitation-does seem to be temp related-I'm with RLighthall - hope we get it in time to test when it still gets cold.

 

[doldenburg]

my truck dont care, sometimes it works great then it acts up. has to be operating temp.

 

[geusterman]

Well, my heart goes out to you guys. My Jan 9 built 3500 has no hesitation from 30 to 60 degrees so far. Can't find one thing wrong with it. I LIKE it! Well, one thing. Tires keep chirping when I take off. Bigger tires should cure that ! George