2008/5.7 - Engine Stalling/RPMs wont climb above 4000

[kapitanius]

Hello,

I have some issues with my 2008 RAM 1500 4x4, 140k miles. From time to time it had always stalled at red lights, but it wasn't that big of an issue. Now, however, it will randomly stall while driving- which is super inconvenient, but other times it drives fine. Below is a rough timeline and what I've done thus far:


TRUCK:
-2008 Ram 1500, 5.7 4x4
-140k miles

ISSUES:

• It used to randomly (once a month or so) stalling at red lights at idle, but now it has the below issues.
• When filling the tank, it refused to start. It turned over fine, but it just wouldn't crank. After 3-4 tries it finally started up and ran ok.
• Yesterday, while driving home I had it stall in traffic on me while going 20+ MPH. I managed to coast to the side of the road and it started after 2-3 tries. After this I got a constant 'ding' sound about every 30 seconds, with the engine light/P0335 code.
• I noticed the RPM gauge would occasionally drop to 0 then jump right back up.
• When I start it while cold and rev the engine, it peaks at around 4000 RPMs then stalls.

DTC CODES:

• P0300 (random misfire)
• P0335 (crankshaft position sensor)
• P1128 & P1129 ( Closed Loop Fueling Not Achieved Bank 1 & 2 - I cleared these and they have yet to return)

WHAT IVE DONE:

• Replaced crankshaft position sensor.
• Replaced camshaft position sensor.
  
• Replaced oil pressure sensor.
  
• Cleaned intake, intake manifold and throttle blade.
• Added a 'new car scent' pinetree thing to the rearview mirror.
• Replaced battery.
  
• Cleaned MAF sensor.

Once I get some time this weekend, I plan on verifying the crankshaft position sensor wiring it good. What do you guys think? Amazon just dropped off a tool that will let me view the data stream - what do you think I should be looking for?
Thanks in advance!

 

[Burla]

Air, gas and spark. If no vac leaks and air cleaner is clean, you cleaned throttle body, so you can rule our air.

Spark Plug condition? Because it has gotten worse if I am reading that right, probably not spark related.

Gas, have you tried various different gases or stay with 91? Have you ran a cleaner through? I like the PEA cleaners like redline s1-1 or amsoil pi. Have you taken a boroscope to combustion chamber? Is there any gas smell in the oil? If so revert back to spark and air.

The main thing is the codes, most of the time we see those the cam is toast and not much will help if that is the case. In your case I think there still is some hope it isn't, but most surely that is a possibility My guess is something in the gas system.

 

[Burla]

Actually winter gas recently started, which could be why it has gotten worse, so oddly the bad news that brings spark back into play.

Did it start dying while driving in august or earlier at all?

What octane have you been using all along?

 

[kapitanius]

Hello Burla,

Thanks for providing some insight. I have been using 87 gas, but am just now realizing the service manual recommends 89. I have half a tank left; ill switch to 91 next time I get gas. I also ordered a fuel pressure tester, which will be here tomorrow. I also plan on pulling the sparkplugs out and inspecting all that stuff tomorrow as well.

I had no idea about the winter/summer gas, but now that you mention it I suppose that could be the case.

When it wouldn't start after getting gas, I thought there could be a fuel pressurization issue as that seemed like an odd time to just suddenly stop working.

I also have a shuperchips programmer that has a 87 program on it- i suppose I could try that. Right now its at the factory program.

 

[Burla]

87 wouldn't cause this, but 87 plus winter gas with less energy will accentuate the issue. Your plugs are a 30k interval right ngk? If they are like 09 then they are 30k mile plugs. If they are old, could be the issue when added to 87 plus winter gas, dunno but good place to start.

 

[kapitanius]

I'm not sure. I know they where changed out about 45k miles ago by the previous owner. I definitely need to get some on order, as long as I'm pulling them out anyway.

 

[Drcc18]

Use a mopar oem crankshaft sensor. The 05 and 07 I had did the same thing. Put in a new mopar oem crank sensor and worked perfect

 

[Burla]

I'm not sure. I know they where changed out about 45k miles ago by the previous owner. I definitely need to get some on order, as long as I'm pulling them out anyway.

likely not it then, but we'll see.

 

[kapitanius]

All,

I figured it out, and wanted to post my fix for those that it may need help in the future.

The first thing I did was check my fuel pressure. It was good to go. I then checked the wiring between the camshaft position sensor, which was also good. I got +5 VDC and a good ground. I did notice that the wiring going to the camshaft sensor was just dangling near the camshaft sensor connector, so I wrapped it up tight and zip tied it in place.

I then replaced the camshaft position sensor with a different brand (I got it at Orilley, yes I know its not OEM..) and it was good to go. It's been rock solid since I began this thread. I'll be driving it across country soon, we'll see if I'll pay for not going with the pricy OEM camshaft sensor!