I have 98 ram 2500 5.9 24v cummins. Very new to diesels.  I have no tachometer and rough downshift between 20-30 mph. I replaced tps. Cam .crank sensors. Really getting frustrated now. I have new ecm. New pcm. Please help. I have tons of money I to this truck I love it but always fix g it and don't know a lot about them . I'm getting codes for crank sensor and tps . Also my a/c blower loses power sometimes not sure if it has a short or what but I been on Google for weeks and just started forum for fist time I'm lost when come to electrical . Thank you. 

First off list all your error codes.

 

As for the blower motor. There is a fuse in the PDC and then there is a fuse in the cab plus the relay in the PDC for the blower.

Now it is pulling up p1764 gov. Press. Sensor low. I replaced it once lest than 5000 miles..

P1762 gov. Press. Offset.

P0751 shift solenoid performance or stuck off. 

P1693 diagnostic trouble code detected in pcm/ companion module

P0336 crank sensor A circuit range/performance.

 

Nevermind your listing of definitions... Now read the diagnostic info for each one.

 

 

Hey Mopar1973Man, in a situation like this could it be a problem in the main electrical supply as a common denominator causing all these error codes to show at one time? I'm thinking bad lift pump, for example, placing an excess load on the electrical system. I cannot see all these parts going bad or going out at the same time and thats tipping my thoughts. 

          Markw, don't throw any more parts at it till we get a chance to get you on the right track. A lot of people know a lot more than I do around here so all I can say is check all your body grounds and positive connections. Clean everything engine grounds, battery posts/clamps. sand any terminals nice and clean. Test the level of A C noise emitted by the alternator. You need a good Fluke volt meter to do that. Check the ground under the drivers side battery, that one's known to corrode. Also read all the articles under second gen engine electrical grounds etc. There is one on how to easily test for the A C volts noise or ripple.

 

Question....1)  is your lift pump powered by the factory lift pump connection or connector coming off of the ECM? 

 

              ....2) .What lift pump are you running?

Edited July 8, 20186 yr by JAG1

In take pump is stock I just replaced this 

I don't have any idea what lift pump brand that is. It could be drawing too much juice thru the ECM. In all brands the lift pump power needs to come off the battery thereby getting the damaging electrical load off the ECM. This is done thru a relay in which the ECM lift pump connection becomes only the trigger for a relay to connect to the battery.

That's an Airtex E7153 fuel pump.   It's rated at 55 GPH at 15-30 PSI and it draws 6.5 AMPS.

1 hour ago, IBMobile said:

That's an Airtex E7153 fuel pump.   It's rated at 55 GPH at 15-30 PSI and it draws 6.5 AMPS.

 

That bad news... AirTex does fine for pressure typically but the volume rating is poor.What happen is idle pressure is good and high but under heavy load it still fails low below 10 PSI typically. Then that power requirement is placed on the ECM directly without a lift pump relay to protect the ECM from direct short or locked rotor. 

Ok so I check and cleaned all grounds replace a couple connectors. Still same issue . I did a fuel press. Test on the fuel filter casing . Banjo bolt from filter to pump and it read zero even when running . First time i did a test like that but is it even possible to start in no pressure at all . 

40 minutes ago, Markw said:

I did a fuel press. Test on the fuel filter casing . Banjo bolt from filter to pump and it read zero even when running . First time i did a test like that but is it even possible to start in no pressure at all

 

Yes, they will start and run with ZERO fuel pressure. It's possible the fuel pump already cooked the ECM in the past. You'll need to test the power and see if the pump is getting power when you bump the starter. 

 

Grounds have nothing to do with the transmission issue. Most like governor pressure sensor and solenoid are bad but you have to read the articles and do the testing to find out. 

Yes because the injection pump can still draw fuel from the tank and keep running , but your causing death to your injection pump by starving it. It needs a minimum of 14 all the time to stay cool and get lubrication. Thats why important to have a fuel pressure gauge and shut it down if too low.

 

If the lift pump shows no fuel pressure who knows if it is causing an electrical overload affecting the rest of the sensors in the system or if it has failed mechanically.

 

I mentioned grounds to help batteries to absorb A/C ripple that may affect the system. Correct me if I'm wrong here.

 

 

 

 

 

Edited July 8, 20186 yr by JAG1

Believe it or not bumping the starter is how I have to start the truck I have a brand new PCM brand new ECM less than a thousand miles on PCM and less than 500 miles on the ECM

I have a gauge on there already I just thought it was broke I just bought the truck couple thousand miles ago replacing little by little I got 6,000 in this truck already on top of what I paid for it and I had shops do half of the work to it because I don't have that much time but it's starting to get to where I can't afford to send it in anymore and I can get the parts cheaper online and what they sell them to me for in the store

. Mark, We are all hoping you find the problem and that you become a long time member of our forum. The articles section is an area that will help you enormously as it sounds like your fuel system needs a lot of changes with right lift pump, pressure gauge, bigger fuel lines etc. Not to mention the electrical upgrades we all have recently discovered by reading W-Ts' articles on grounding issues. Mopar1973 man has helped loads of people around here getting us all on the right track with our second gens.

Thank you 

 

If you have no fuel pressure maybe try hot wiring the lift pump to see if it does indeed work.  Also, no matter the outcome of all your issues I suggest adding 2 stroke oil (TCW3) to your fuel (1 ounce per gallon).

 

You just have trust these guys here. They really know what they are talking about and follow ALL their advise.  They will definitely get you up and running.

 

L8tr

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