engine revs on its own! why?

[PaulBarker]

first off, my truck is totally stock right now. i have done nothing to it at this moment. 6900miles on it



ok, with the e-brake on and with the auto transmission set to 2nd gear. when i hit about 2000 to 2500 rpms and let off of the gas pedal the engine would rev up two times on its own. then the e-brake would come on and the engine would idle back down normally. it does not do it with the e-brake off. why? i have not tried it in any other gear. this happened earlier today. i now there are a few dodge mech on here, what do you think. it is definitely electronic and not over fueling. so is that normal.

 

[RVanWagnen]

not trying to hijack your thread, but mine is a 6spd manual, and when your trying to go in a hurry between shifts why does the motor rev up higher even though your off the gas for a second?

 

[mattymac]

not trying to hijack your thread, but mine is a 6spd manual, and when your trying to go in a hurry between shifts why does the motor rev up higher even though your off the gas for a second?

Since your loading the motor more by driving faster things such as, rail pressure, and duration are increaced and mainly the extra rail pressure cant bleed off quick enough so the injectors squirt an extra bit of fuel into the cyls causing the post rev.



on the earlier trucks (03-04 non 325 hp motors) This was a programming issue where the trucks would raise or at least hold RPM durring shifts.

 

[PaulBarker]

but it only does it if the e-brake is on. so i believe it is eletronic problem and it doent feel like over fueling

 

[Drdorian]

ok, with the e-brake on and with the auto transmission set to 2nd gear. when i hit about 2000 to 2500 rpms and let off of the gas pedal the engine would rev up two times on its own. then the e-brake would come on and the engine would idle back down normally. it does not do it with the e-brake off. why?

PaulBarker, what is the increase in RPM's that you are seeing?



The issue sounds like the torque converter locking up. In order for the exhaust brake to work the torque converter needs to be locked, if there's a slight speed mis-match you may be feeling, and seeing, the converter lock up.

 

[PaulBarker]

about 250 to 400 rpms, i dont believe it is from the tc locking up and forcing the engine to rev up twice. it feels and sounds like i was to push the gas pedel let off push it again and let off, than the e-brake would kick in.