Anone have this problem?

[Simms]

I have a friend with an 04 3500, 6-speed, with 52,000 miles.



The engine goes into default mode and will not exceed 1000 rpms until it wants too. You can be driving on the highway or shifting gears in a parking lot and it will go limp and stay at 1000 rpms. There is no rhyme or reason, it will do it 50 times on a 5 mile drive or it will not do at all for a 500 mile drive. Warm or cold engine temp. Seems to act up more so in the rain or wet conditions. It is as if the passenger reaches over and turns off the key while you are driving. The truck does not stall and will pull to 1000 rpms but no more. You can hold it to the wood, depress the clutch or shift gears, there is no cure. It will come back to life as if it never happened.



Anyone have any advise on what this possible could be?



Thanks!

 

[Bob4x4]

Have you pulled any codes?



Bob

 

[DieselFiend]

First thing I'd check is the fuel filter. Find out the last time it was changed. Even if it was just changed in the last 200 miles, I'd change it again just to rule that out. Then I'd go to the dealer for codes.

 

[TowPro]

The 1000 fixed RPM sounds like some kind of limp mode. Is this year truck "drive by wire" as far as the accelerator pedal? if so my bets are on a bad throttle position sensor. The ECM sees a reading it don't like, then sets the RPM at 1000 so you can drive it to the dealer. I bet there are codes, how about doing the on off on off 3 times thing then read the codes off the odo?



VW does the same thing.



Just an edgeamacated guess

 

[amsoilman]

I have a friend with an 04 3500, 6-speed, with 52,000 miles.



The engine goes into default mode and will not exceed 1000 rpms until it wants too. You can be driving on the highway or shifting gears in a parking lot and it will go limp and stay at 1000 rpms. There is no rhyme or reason, it will do it 50 times on a 5 mile drive or it will not do at all for a 500 mile drive. Warm or cold engine temp. Seems to act up more so in the rain or wet conditions. It is as if the passenger reaches over and turns off the key while you are driving. The truck does not stall and will pull to 1000 rpms but no more. You can hold it to the wood, depress the clutch or shift gears, there is no cure. It will come back to life as if it never happened.



Anyone have any advise on what this possible could be?



Thanks!

Sounds like a (TPS) Throttle Position Sensor to me.



Wayne

amsoilman

 

[Pawpaw]

There was a recall on 03 & 04 trucks for poor sealing at the ECM connector. Your mentioning that it seems to happen more in the wet reminded me of this.



Go to this site: http://www.dodge.com/owners/index.html



In the center of the page, under "Recalls", plug in the last 8 digits of the truck's VIN number to see if there are any outstanding recalls.



Bob

 

[NUKEMAN]

Okay, I've entered my VIN 5 times (last 8) and every time it says "Not a valid VIN". Any ideas?

 

[Bob4x4]

There was a recall on 03 & 04 trucks for poor sealing at the ECM connector. Your mentioning that it seems to happen more in the wet reminded me of this.



Go to this site: http://www.dodge.com/owners/index.html



In the center of the page, under "Recalls", plug in the last 8 digits of the truck's VIN number to see if there are any outstanding recalls.



Bob

That is PCM,on the firewall



Bob

 

[Bob4x4]

Okay, I've entered my VIN 5 times (last 8) and every time it says "Not a valid VIN". Any ideas?

Make sure you are entering all didgets correctly ie numbers not letters and vise versa where needed.



Bob

 

[K LeClair]

TPS sensor???I thought only Automatics had a throttle position sensor

 

[mberry]

I'm pretty sure all '04 and over have a TPS since they went "fly by wire".

 

[hoogkar]

Dead Pedal

I have a 2003 with HO and six speed, this has been going on for over a year and a half and has been to the dealer many times - they still have not found the problem because it is intermittent.

They have replaced the TPS unit -did not do any good! It never throws a code, I check each time it happens.



This happens to me mainly when I go into a coast mode down a hill and then try to accelerate - the pedal is dead. It has also occurred several times when I cold start the vehicle-I try to press on the pedal and it does absolutely nothing.



I have since found out that when it happens when I am moving on the road if I rapidly depress the accelerator several times or turn my exhaust brake on and off a couple times it seems to shock the system and the pedal comes back.



Still no help or cure from the dealer - they tried to put a monitor on the ecm but it would not work on the deisel. Just need to drive it till it quits - thats the DOGDE DEALER philosophy!

 

[Pawpaw]

That is PCM,on the firewall



Bob

My quick search on the subject confirms your statement, but that just leaves me confused... '04's don't have a PCM, but were included in that recall.



I took my truck in for that & the transmission line recall at the same time.



Bob

 

[Bob4x4]

My quick search on the subject confirms your statement, but that just leaves me confused... '04's don't have a PCM, but were included in that recall.



I took my truck in for that & the transmission line recall at the same time.



Bob

600 series don't... ... ... ... ... ...



Bob

 

[Pawpaw]

600 series don't... ... ... ... ... ...



Bob

Neither does my early 04 305/555.



Bob



(Do you feel like you're talking to yourself, Bob? )

 

[jelag]

rhooqkamp..... your describing an exhaust brake that is stuck on... ... are you sure your's isn't stuck in the on position when this happens...



Our trucks are fly by wire... . I've not see one with a bad TPS that didn't throw a code... . I have seen the cam position senor give some problems and the truck go into a limp in mode like is suggested... . and not throw a code... .

 

[DShehi]

Limp mode

I have a 2003 3500 HO auto 4x4. In the past three years it has gone into limp mode at least 1/2 dozen times. Other times is will have a loss of power. By this I mean, pulling my antique tractor (10,500lb est) up a multimile grade leaving Camp Verde, sometimes I go up at 40mph and other time at 60mph. My limp mode/loss of power, problem has always been leaving Camp Verde pulling up the multimile interstate highway grade. Topwards the top it will go into limp mode, leaves no codes the dealer can find. Last time for limp mode was a year ago, then I pulled my RV 3500 miles without a problem. As I only use my 3500 for pulling my RV and hauling my antique tractor around northern Az. Only 30,000 miles on my truck.



Don Shehi

Camp Verde, Az

 

[amsoilman]

I don't think "Limp" mode would give you 40 MPH, especialy with a load!



My . 02 worth



Wayne

 

[Bob4x4]

I have a 2003 3500 HO auto 4x4. In the past three years it has gone into limp mode at least 1/2 dozen times. Other times is will have a loss of power. By this I mean, pulling my antique tractor (10,500lb est) up a multimile grade leaving Camp Verde, sometimes I go up at 40mph and other time at 60mph. My limp mode/loss of power, problem has always been leaving Camp Verde pulling up the multimile interstate highway grade. Topwards the top it will go into limp mode, leaves no codes the dealer can find. Last time for limp mode was a year ago, then I pulled my RV 3500 miles without a problem. As I only use my 3500 for pulling my RV and hauling my antique tractor around northern Az. Only 30,000 miles on my truck.



Don Shehi

Camp Verde, Az

If in fact your truck leaves no trace for the dealer to find (which I doubt) I would replace the fuel pump. I have seen many fade before going belly up. When the truck derates it will leave a freeze frame in most reported cases I see.



Bob

 

[betterthanstock]

I have a 2003 with HO and six speed, this has been going on for over a year and a half and has been to the dealer many times - they still have not found the problem because it is intermittent.

They have replaced the TPS unit -did not do any good! It never throws a code, I check each time it happens.



This happens to me mainly when I go into a coast mode down a hill and then try to accelerate - the pedal is dead. It has also occurred several times when I cold start the vehicle-I try to press on the pedal and it does absolutely nothing.



I have since found out that when it happens when I am moving on the road if I rapidly depress the accelerator several times or turn my exhaust brake on and off a couple times it seems to shock the system and the pedal comes back.



Still no help or cure from the dealer - they tried to put a monitor on the ecm but it would not work on the deisel. Just need to drive it till it quits - thats the DOGDE DEALER philosophy!

I would insist that they replace the ECM in your case. Way back when computer controlled cars first came out, my sister had a car with the same problem. Towed it to the dealer and replaced some stuff, then it happened again. My dad insisted they replace the computer. The guy said they never fail, but then finally after 3 tows and mention of the lemon law, he swapped a new ECM and it went trouble free for a quarter million miles.



All it takes is one intermittent transistor in the logic part of the ECM, and it freezes, not knowing what to do.



I know they make the computer to be such an expensive part, but it's not. It's just one flexible PCB bent (U-shape) inside the aluminum case, with a few microprocessors, memory, and some power transistors for the injectors, and I think some foam to keep it from rubbing and shorting out the components. $200 tops.