Hemi Problems

[jarrod_36]

hey all. i have a 2007 ram 1500 5.7 and i am having issues with it. During roughly the first 10 minutes or so of driving it and i pull up to a stop light or sign and stop, its like it stalls out or chokes itself out and shuts off. the engine is already warmed up and it does it alot when its cold out like today (15 degrees here). it is driving me nuts. i replaced all the plugs and the EGR valve thinking maybe that would help but to no avail. any help with this would be greatly appreciated.

 

[MoparMulisha]

How many miles on that beast?

 

[jarrod_36]

its got 150,000. mostly all highway

 

[RonJon '06]

Any codes? Does it run fine the rest of the time?

 

[jarrod_36]

it has one code that reads P1521 which i am told is incorrect engine oil type, although i am running kendall sun blend 5w20. after the first like 10 minutes when i stop the rpms drop to about 500 then go back up to 700ish.

 

[MoparMulisha]

Hopefully it's nothing with the fuel filter or anything because if memory serves me, you have to drop the entire fuel tank to service it.

 

[jarrod_36]

yeah either that or i can lift the box off.

 

[RonJon '06]

There was a TSB for the 2006 5.7L but I would think that they fixed it for the 2007.





Edit: TSB 1800808a for the 2006 5.7L Hemi, sounds like the same problem you're having.

 

[jarrod_36]

what was the repair for this or what did the TSB say? i cant find it

 

[RonJon '06]

what was the repair for this or what did the TSB say? i cant find it

The fix was to take it into the dealer and have it "flashed" or re-programed but I don't know if this is your problem. Did you disconnect the throttle body when you changed the sparkplugs? Do you have MDS? When I took my oil pan off at 166K miles there was so much sludge that the oil pick up screen was over 50% blocked. I'm wondering if sludge could be effecting the oil viscosity and affecting your MDS since that is the code that is coming up.

 

[jarrod_36]

No I did not disconnect the tb. Yes I have MDS.

 

[RonJon '06]

If P1521 is the only code you're getting I would try changing the oil and filter even if they are new, maybe with a different brand. You could try putting it in tow/haul mode to disable the MDS and see if it still acts up. Maybe try replacing the oil pressure and temp sensors since these are what the PCM uses to determine the oil viscosity. That's where I would start.