2001 Dodge Ram 2500 V10 Misfire Counter

[Piekar]

I can't get the misfire counter to show any misfires. Anyone run in to this before? On the misfire counter page there is a PID "ADAP DONE LEARN" and it reads NO. I haven't been able to find any info on how to perform this, or how to change it Yes.

Thanks for your help!

[Witsend]

If there is something wrong with the vehicle that makes it stay in open loop mode or crankshaft position is not learned, and cam crank sync has not been established, it won't count misfires?

[Piekar]

I have no fault codes stored in the vehicle, and the computer does go in to closed loop. The "CURRENT SYNC" PID reads "OK".

[Billcmat]

Dodge Profile Relearn

On a hot engine, drive it to 60 mph and decal to 40, NO BRAKE APPLY!
May take 2-3 times doing this and the learn PID will change to YES.

Then misfires will count up. If you learn it with a miss, it will not show it. If already missing, find that first before the relearn.

[Witsend]

That's good information but pretty Sh@tty that after clearing codes on an old Dodge that it likely will lose all it's misfire history and ability to detect a misfire on a currently misfiring cylinder.

[Piekar]

Thanks! I'll give that a shot. I've had to do that on many different Fords before, maybe it'll work for this dodge.

[Piekar]

I never got the PID to change, and still doesn't pickup any misfires. The truck was not misfiring during the decels.

[Scott_65]

I have had some vehicles that had a tendency to only count electrical misfires. If it was a mechanical issue, it wouldn't be counted. I don't know which vehicles specifically, but something to consider. Perhaps try a compression test and see if you have a mechanical issue somewhere. If so, that will locate your cylinder and probably also explain why it wasn't counting them.

I know that most, if not all, new-ish computerized ignition systems use the crank sensor to count revolutions and determine misfires based on the exact timing of when the crankshaft slows down. It simply lines that up with which cylinder should have been firing at that instant. Based on that setup, it should count misfires regardless of cause, which most late models do. But I don't believe all systems worked this way in the past.

[Skip]

Chrysler looks at the rotational speed of the crankshaft under power. The PCM takes a snap shot of the ckp sensor pattern when in fuel cut off decal and stores it. That is called the Adaptive Numerator. If this is not learned, it can not see a miss. At the bottom of the Misfire Counter test screen is the PID to tell you if it learned or not.

[Piekar]

I see the PID and its says, NO. What is the learn procedure? I have done close 50 decels from 60 to 40 with no change.

[Witsend]

I wouldn't waste my time waiting forever and a day. Clean the throttle body, Check the long fuel trims ,Check the fuel quality , spray or smoke check the intake, check the fuel pressure ,check the fuel pressure holds and regulator not weeping gasoline into the vacuum hose, check the EGR valve for leakage, Relative compression check with the inductive amp probe. Dampen the wires, and coil and check for arcing in the dark while someone brake torques The Turd.

[Piekar]

I'm trying to learn something new, something that might save me time and frustration in the future.

[sbreland73]

I'm trying to learn something new, something that might save me time and frustration in the future.

I agree, stick to the issue you have at hand, leave the blanket methods for those not in the know. If you are having difficulty with the re-learn, there could be some problem that is preventing that process from occurring. Some enable criteria not being met perhaps.

[Witsend]

I'm trying to learn something new, something that might save me time and frustration in the future.

Higher education for a good technician to become closer to a engineer takes time and money that your customer who is driving a 15 year old Dodge, likely does not want to pay for, unless it is your own personal vehicle or you aren't charging the full time

http://www.dodgetalk.com/forums/showthread.php?t=282003

[Piekar]

Nobody said anything about the customer. Also, nobody said anything about getting a degree in engineering. The truck has been fixed for a while, just needed a ignition coil. All I asked for, was to get my misfire counter on my Verus working.