2004 (early production without HO motor) Ram 2500 Cummins Turbo Diesel regular cab, 4x4 with automatic trans. Currently has 236K. Bought the truck with 220k and was told from the previous owner that he did injectors, and lift pump at 200k. I did fuel filter with an oil change at 230k. It's been running great for the 16k I've had it until last week.

I drove the truck to work about 30 miles to work with no problems. I went out for lunch and when I started the truck and put my foot on the brake to shift into reverse, it stalled. It's never done that before. I was suspicious... I got about 2 miles from my office and when I approached a stop light and hit the brakes, it stalled again. It started right up and I drove another half mile when at another light, it stalled again upon hitting the brakes. I started it again and pulled into he pizza shop parking lot. I put it in park and listened to the motor. It was louder than usual with a prominent diesel "clackety clack".

I had my lunch and came back to the truck about 30 minutes later. It started easily but now had a CEL. I gingerly drove it home about 30 miles. The idle remained noisy and rough. The engine sound was loudest at lower RPMs and got quieter as the motor revved up a bit. Above 1200 RPM it sounded normal. Above 1450 RPM it was quiet without any typical diesel clackety clack. At 1500 RPM it lost power quickly.

When I got home I pulled the code P0088 Fuel Rail/System Pressure - Too High

I did some reading up and was directed to the Fuel Control Actuator (FCA). I inspected mine and saw that the female connector on the back of the FCA was broken off. The pins were still there and connected to the plug but I figured, this thing is obviously busted so it could very well be my problem. I ordered a new one, installed it and the truck ran. I took it for a 3 mile test ride and had no CELs and seemed to fixed..... There was one funny thing I noticed though. The interior lights were dimming for a few seconds and then would go bright again for a few seconds and then dim again, and on and on. It was as though some heavy electrical draw was kicking on and off such as the grid heater. I don't know if the truck always did this and I just didn't notice or if it started recently.

The next evening, I jumped in the truck to go out for some food and one mile down the road it started losing power and stalling. I limped it home and it was still doing the lights dimming thing. It did not throw a CEL. I parked it for the evening.

Today I cleaned up all the battery connections. I removed each terminal, brushed it well, removed any corrosion which there was little of really only on the passenger side battery negative terminal. Connected everything back up. Didn't fix my issue. I did notice that the thick red lead coming off the alternator is corroded green and the insulation is starting to crack.

I checked the grounds I could see and they looked fine. The ones that go to the fenders all look completely clean and solid. I took a quick look at the battery crossover cable and it looked fine.. no obvious breaks.

I thought that maybe air got into the system when I replaced the FCA so I read up on how to bleed the system. It's a "self-bleeding" system and all you have to do is turn the key to crank for a split second (not enough to start the truck but just enough to engage the starter for a split second) and then the lift pump will run for 25 seconds which should prime/bleed the fuel system. I did this a few times then started the truck. It ran poorly, was hesitant to rev, varied between smooth idle and a loud detonating idle and then stalled. This time it threw a CEL for P0088 fuel rail pressure too high again.

Also, I noticed that the voltage gauge on the dash was registering 12v upon start up and would jump to 14 after running a little while and revving the motor. I'm wondering if I have an alternator diode failure causing AC noise type issue that I've read about on the forums.

Anyone got any ideas? What to check? How to diagnose?

 

Anyone have any input here? I'm most concerned about the p0088 code and getting it fixed as I can't drive this truck the way its running.

 

Did you correct the corrosion problem with the red power cable? These trucks are picky about voltage. It causes all sorts of issues. The only thing I can think about the power dimming, may be the grid heater coming on. I would start with the cables first before I went deeper.

 

It sounds like over fueling. Do not just buy parts and shot gun this thing. Recognize that you do not have the tools to troubleshoot the fault. Go to a shop that has the equipment and expertise.....it's cheaper than buying unnecessary parts. I suspect you have a leaking injector.

 

I agree with Steve, don't shotgun parts. I would also do the maintenance items 1st. Such as clean battery connections, and have them load tested. Check and clean all your grounds and any heavy power connections that you have. Nothing worse than paying money to a shop to do those items. They will start at that stuff, too. At least that way you can tell & show them what you've already completed.

 

I cleaned all the battery terminals and there was very little corrosion. The wire off the back of the alternator has a little bit of corrosion but nothing bad.

Trying to focus on the fuel pressure issue right now first.
Today I tried to do some testing of the FCA circuit. I turned the ignition to ON, unplugged the FCA connector, put an incandescent test light across the terminals on the connector and after a few seconds it flashed brightly.

I also then turned the key off and turned it back on and the test light would flash then as well.

I checked the connector for corrosion and used a pick to snug up the pins so they would make a better connection with the FCA pins.

I also changed the fuel filter. None of this helped at all. The truck is still idling rough, noisily, stalling and has loss of power.

What do I do next?

 

bump....

 

Since you don't have anything to read the reported RP reading and the real RP reading, try a known good fca.
If the fca was good then it's the RP Sensor issue.

 

The shop replaced the rail with sensor and overflow valve. That didn't fix it. Then they replaced the CP3 pump. Said they'd fixed it. Had it back and 50 miles later, the same problem reappeared. This has officially turned into a nightmare. ***!!!

 

Just an off chance, crawl under the front and check your crankshaft sensor..
if its coated with dirt, or broken, its not sending the proper info to the ECM, which uses that info to send pulses to the FCA... It can cause major drivability issues such as clattering starts, surging and dieing out..
Im dealing with those myself right now..

 

It's back at the shop and they're still stumped. They've got one used "known good" FCA that they keep on the shelf for testing purposes that will get the truck running right but they're worried that the truck will eat up that FCA after not much longer. Their next steps are to pull the fuel filter and cut it open to look for contamination.

After that, I'm sure they're going to tell me that I need to replace the ECM.

I've got a few questions of you diesel gurus:
Does anyone know a way to bench test a FCA?
What is the voltage range that a fuel rail pressure sensor should read from 0 psi up to 26,000 psi?
How can I test the FCA output signal from the ECM to the FCA?

Here's my logic in asking these questions.... If the rail pressure sensor (which is brand new) signal is not reaching the ECM correctly, then the ECM won't be able to calculate proper fuel pressure. If a wire from the pressure sensor is shorting out and the ECM is seeing a false zero rail pressure signal, then it will call for more and more fuel and this would explain my symptoms.

If the ECM is getting proper signal from the pressure sensor then I should be able to test the output of the ECM to the FCA to see if it is sending the correct signal to it. I believe this is pulse-width modulated so I'll need to use a real big boy scanner tool.

If I can measure these two things, then I should be able to diagnose whether the problem is in the ECM or the wiring to the ECM.

 

Found contamination in the fuel filter that seemed to only get sucked up when the tank was very low. They dropped the tank and said that the screen on the pickup was torn and there was gunk in the tank. They sent the tank to a radiator shop to be flushed and then reinstalled it. The fuel pickup is no longer available from Dodge because they did away with that style and replaced it with an in-tank pump unit. My lift pump is on the fuel filter unit under the hood. I didn't want to switch to the new in-tank style so, we put an in-line filter just before the lift pump. After all that the 3rd FCA is still bad. They tried to clean it out but it is not working so we are awaiting a replacement. Hopefully, with the new FCA, a clean tank and a pre-lift pump filter, the problem will be solved.

In your guys' opinion, what should I do about the billing for all this? The long and the short of it is that I brought the truck in for this problem and they gave it back to me after a $2,640 bill to replace the fuel rail and CP3 pump and the problem was not remedied. I'm sure there's going to be another bill coming for about $500 for the tank cleaning. Over $3k is a lot of money to pay for a shop to diagnose that my tank was grimy.

Oh, and I'm still not 100% certain that the problem will be completely fixed after this. I'll need to test drive it a few hundred miles first.

 

If they worked on the problem, they need to get paid or they go out of business. No shop gives a correction guarantee. They made their best guess. Sometimes we're wrong. That's the maintenance business. The problem is yours, not theirs. You brought the truck to them because you could not fix the fault. Nobody has a crystal ball. No question, this is both unfortunate and expensive. Shot gunning parts is always bad. You're depending on luck, no matter who does it. You received advise from both me and others on this thread not to do this and you are now paying the price. You need to physically measure your fuel feed pressure at the CP3 inlet banjo and the fuel rail to see what is happening and at the same time monitor the sensors. It is only at this time you will know if the fault is real or it is sensor error. Even after spending all this money, you still do not know. Remember you need a minimum of 5000 psi at the rail before the ECM will fire the injectors at start up. Correct rail pressure will range between 5000 and 17,000 psi depending on your right foot and this is monitored by the ECM.

 

Any update????

 

Got the truck back after another $800 bill bringing my total expense for this problem to $4,000 including parts and labor. After the tank flush, another new FCA and an inline filter before the OEM filter, the truck is running right again. I've put 250 miles on it and it seems fine.

I just don't feel right that the shop banged me for $4k to figure out that there was fuel contamination. Shouldn't that be one of the first things they'd check???