Engine/Transmission (1998.5 - 2002) help! bucking bronk

[Agades]

I ve been fighting a slight stumble or shake problem for two months



paid $50 this morning for a tech to take my pickup for a drive and to be told my pickup is putting out too much boost for the fuel calibration (lean condition)



this does not make any sense to me. My pickup is one of the few that sucks more fuel than it should (9-16mpg)

furthermore I cannot get my pickup to shake or stumble at all when using the cruise control to increase or decrease speed. As soon as i shut off the cruise the stumble is back again.

Usually the shakes show up when accelerating in 4th to 5th gear and about 8 - 15 psi boost (not WOT). My gut feeling is APPS

Does this make sense? Is the throttle controlled by the same sensor when cruise is on? One of the vendors that I have bought aftermarket products from told me that my cruise should hold the pedal in place (vacuum controlled). Mine does not . It returns to 0. I think he is thinking of a 12 valver. :-{}

 

[kaffine krazed]

I'm not positive on the 5sp but I know on the 6sp the cruise is completly electronic. Look at the APPS if there is only 1 cable going into it then the cruise is electronic not vacuum. You can also look to see if there is a vacuum modulator for the cruise control it is located under the drivers side battery. The autos use a vacuum cruise control because the trans needs the throttle cable input.

 

[Agades]

I only have one cable and one set of wires plugged in the bottom of the housing



So the ecm takes over the fueling when cruise is on??



what controls rate of acceleration??

combination of MAP and APPS??

 

[Hohn]

I may be wrong, but is sounds like the APPS to me. I *think* that when you turn on the CC, the ECM takes over fueling/throttling control and the APPS is not in the circuit. That's why on our trucks, the pedal comes all the way back up when the CC is on. Rather than trying to hold the pedal a certain spot to maintain speed, the ECM eliminates the pedal as a factor, and controls speed via RPM input.



It's similar to a drive-by-wire setup. With the CC off, the pedal tells the computer what you want, the computer determines what you actually get. With the CC on, you have made your input in the computer's eyes, so the pedal and its associated stuff gets ignored.



Someone correct me if I am wrong...



Hohn

 

[Agades]

called the tech who worked on my pickup

he said that the voltage on the APPS was rock solid when the stumbling was occuring



my pickup is in crappie flop mode



yesterday morning got codes 0235 and 0500

these codes only show up when its really cold (below -5)

dealer cant find any problems relating to this code



any one want to buy a pickup????

 

[Agades]

did that

doesnt stumble any where near as bad

but if i hold the button it wont let it go WOT

i get about 24 psi boost versus 35psi with pedal

 

[CFAR]

Chrysler/Dodge/Plymouth P0500 No vehicle speed sensor signal detected during road load conditions



And the dealer doesn't think this could be related?



Anybody know what a 0235 code is?

 

[Agades]

the 235 code is FUEL PUMP FUEL VALVE OPEN CIRCUIT



this code only shows when below -5 degrees and the light shuts off itself once pickup is warm and cycled key a few times



the tech told me that dodge said this is normal to show up when it is really cold with the new computer flash

("yah right")



(dealer did a computer reflash to set high idle feature)

(even though they didnt need to)



crawled under the pickup last night to check wiring on the speed sensor



the tech broke the little retaining clips that hold wiring when he put in my clutch. So I fixed this hoping the wires were shaking and causing a bad connection



also cleaned IAT

also took apart and cleaned all connectors except ecm and pump

dealer put in a new pcm

checked voltage on map

tech supposedly checked voltage on APPS and rock solid

( I say supposedly because I didnt see)

sent in ufm to DD and came back OK





no 0500 code yet but pickup still shakes



I feel something is screwed up in the ecm relating to the new flash

but dodge and cummins wont even talk to me



( I am one of those savage heathens who need more power )







Oo.

MY PICKUP DID NOT SHAKE UNTIL THE DEALER PUT IN MY CON OFE AND DID THE REFLASH

this should be fixable