Engine/Transmission (1998.5 - 2002) gutless bl##y wonder

[2-ND TIME]

Thanks

Thanks Steve will try this on the next 5 or 6 days while I am away. 1200 RPM is where I get maximum bucking from the engine. Appreciate this info, Thanks.

 

[2-ND TIME]

G/b/w

Well have info from the last days of having to suffer with this . Lift pump did get it down to 8. 5 LBS pressure at one time but the rest was at 9. 5 min pressure. At 70 MPH I was getting 2 to 4 LBS boost. most of the time went up to 6 once. 4 times at the 50 to 55 MPH I was getting 6 LBS boost. L/P was around the 10 PSI. Unable to say what pyro temps were will have to get work to be able to pay for that. It is surprising how one can go up and down hills and still be on no boost or 1 LB. Had to stop on a 8% grade and start off so was good time to see what it would do. NADA. 1st gear ran it up to 3000 and got nnooooooo boost L/P was at 11 lbs. 2nd gear about 2900 and noooo boost. 3 rd gear got boost at 2700 3/4 lbs of boost. 4 th gear laboured hard to get above the 1600 rpm were boost started to come on. Boost stayed steady at 19 once it got going and everone else was long gone. Would rather have had the Kenworth water truck with 800,000 KM's with the N-14 loaded with 2500 GAL water then it would have been faster accelerating. When it is fueling better there is less noise of the valves. Boost starts some times at 1600 in 4 th gear and sometimes at 2200 RPM up to that time it just reves and makes noise and takes about a 1000 RPM loss to shift gears. At least and over loaded box truck with clay towing backhoe up a 8% grade with doing a full shift you only loose 300 rpm and it cranks out the power. :--) Thinking about the way it operates it gets one signal from the off-idle, next signal from the speed sensor and the third is from the MAPS. For if you stick your foot in to it it does take a second to get it to start performing.

 

[Steve St.Laurent]

Well, you definately have a problem. Based on the fact that once it went to 19 psi it stayed there I don't think you have a leak in the intake system. You are not building boost anything like you should be though - your truck truly must be a dog with those numbers. It almost sounds like a stuck wastegate to me since I don't see how you could get up to 2900 rpm without any boost others. 2900 rpm should have enough airflow to be creating boost pretty much no matter what. That's where I would start anyways. Try to find a different Cummins shop than the one you tried before and print out this thread and give it to them. The info here will help them. They should be able to help you.

 

[Bob4x4]

A bad map sensor may not set a code... . with a scanner connected watch the boost seen by the ecm versus what you see on your gauge. I have had many map sensors fail this way. It will be very sluggish out of the hole then be be weak although better at a cruise rpm... ... . like a non-turbod diesel.



Bob

 

[2-ND TIME]

Thanks

Thank You Steve. Sorry, stuck wastegate I have removed it checked it out for travel and it's ability to seal seams good have pulled the line off and there was nnoooooo difference and cummins checked it out with there air system and said it was good. This is the reason that I am sure that the problem is the off-idle validation cct and the very high resistance. The ECM isn't see the off- idle and is fueling accordingly as I rev it up until it recieves a signal from the MAPs or speed sensor or both.

Bob4x4 I am on my 4th Maps and they have never made the system work when a new one is installed???? The resistance of them all measure fairly close to one an other. So am at a loss to say that one was bad???? Have talked to 8 different chrysler dealerships and they know not of this. Have talked to most of the cummins in BC and Alberta and they know little of how to fix this. What I can do when I can afford it is check the % throttle versas % ??? HP Is that the one???:{ :{ :{ Thanks still need more info please.

Read the one thread on the short on pins at the wiring harness form the ECM this should provide a premanant signal that the engine is at off - idle and fuel accordingly.

 

[A Johnson]

Some times it is the pigtail on the boost sensor. I have no explanation for it as it may ohm out good and appear to be making solid connection, yet the pins will wear in some fashion so that the signal does not get through correctly. I realize you are on your 4th MAP sensor, but if it was my engine i would change the pigtail on the wiring harness for good measure. Also has anyone checked exhaust restriction? It will act much the same as a loose CAC hose if it is too high. Not sure what the Dodge spec is for restriction, but should probably be less than 4. 5" mercury when running a catalyst, and under 3"Hg with only a muffler.



A Johnson

 

[2-ND TIME]

Maps

The exhaust pipe I took off some time age and there was no cahnge how it operated. Didn't check the actual restriction so am guilty there. Cummins makes a pigtail that one can monitor the voltage and havn't done that yet! But did measure the voltage and move things around as I could and didn't find anything wrong but will think about changing the maps connector. This is the technique that they both have been using so far and has cost me over $12,000 so, far so need to come up the answer if I can. MORE info please. Thanks.

 

[Jonweaver]

What Power ?

Get a B&D Speed Eliminator to get rid of Dodges torque management . Also

either clean your current MAP sensor or buy a new one .

 

[Lordsman]

Have you checked the fuel tank to make sure the vent cap was removed by factory during assembly. If left on there will be a vacuum created in tank which will reduce engine power because lift pump will be fighting against it.

Most caps are red, some black. http://dodgeram.org

See Fritz's Dodge Ram Tech/low power.

 

[2-ND TIME]

99 garbage

havn't found the plug that you speek of but leaving the cap off doesn't change the way it runs (usless) the MAP pins seam to be good no corrosion ( can't spell it ) and changing the Map hasn't made it run better before so not going to waste my money till get a definant answer on the junk.

WHAT JUNK!!!!!!!!!!!!!!!!!

 

[Steve St.Laurent]

An OBD II scanner will tell you exactly what all the sensors are sending to the ecm because the ECM is what's being read. You can read it live while you drive the truck. By doing that you'll know if the APPS, MAP, and IAT sensors are reading appropriately and whether there is an issue with the wiring harnesses to them.